土木工程专业英语结课论文

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关于土木工程英语作文

关于土木工程英语作文

关于土木工程英语作文英文回答:Civil engineering is a broad and challenging field that encompasses the design, construction, and maintenance of the built environment. As a civil engineer, I have the privilege of working on a wide range of projects, from bridges and roads to buildings and water treatment plants.One of the most rewarding aspects of civil engineering is the opportunity to make a tangible difference in the world. The structures that we design and build have adirect impact on the lives of people and communities. For example, a new bridge can connect isolated areas, a new road can improve access to essential services, and a new building can provide shelter and comfort for those who need it.Another aspect of civil engineering that I find particularly interesting is the challenge of constantlyinnovating. The field is constantly evolving, and new technologies and materials are emerging all the time. This means that civil engineers must be adaptable and willing to learn new things.Of course, civil engineering is not without its challenges. One of the biggest challenges is the need to balance the competing demands of safety, cost, and sustainability. Civil engineers must be able to design structures that are safe and reliable, but they must also be mindful of the cost of construction and the environmental impact of the materials used.Another challenge is the need to work with a variety of stakeholders, including clients, architects, contractors, and government agencies. Civil engineers must be able to communicate effectively with all of these stakeholders to ensure that the project is completed successfully.Despite the challenges, civil engineering is a rewarding and fulfilling career. I am proud to be a part of a profession that makes a real difference in the world.中文回答:土木工程是一个既广泛又富有挑战性的领域,涵盖了建造环境的设计、建造和维护。

土木工程专业英语论文.doc

土木工程专业英语论文.doc

Building construction concrete crack ofprevention and processingAbstractThe crack problem of concrete is a widespread existence but again difficult in solve of engineering actual problem, this text carried on a study analysis to a little bit familiarcrack problem in the concrete engineering, and aim at concrete the circumstance put forward some prevention, processing measure.Keyword: Concrete crack prevention processingForewordConcrete's ising 1 kind is anticipate by the freestone bone, cement, water and other mixture but formation of the in addition material of quality brittleness not and all material.Because the concrete construction transform withoneself, control etc. a series problem, harden model of inthe concrete existence numerous tiny hole, spirit cave andtiny crack, is exactly because these beginning start blemish of existence just make the concrete present one some not and all the characteristic of quality.The tiny crack is a kindof harmless crack and accept concrete heavy, defend Shen anda little bit other use function not a creation to endanger.But after the concrete be subjected to lotus carry, differencein temperature etc. function, tiny crack would continuouslyof expand with connect, end formation we can see without the aid of instruments of macro view the crack be also the crack that the concrete often say in the engineering. Concretebuilding and Gou piece usually all take sewer to make of,because of crack of existence and development usually makeinner part of reinforcing bar etc. material creation decay,lower reinforced concrete material of loading ability, durable and anti- Shen ability, influence building of external appearance, service life, severity will threat arrive people's life and property safety.A lot of all of crash of engineerings is because of the unsteady development of the crack with the result that.Modern age science research witha great deal of of the concrete engineering practice certificate, in the concrete engineering crack problem isineluctable, also acceptable in certainly of the scope justneed to adopt valid of measure will it endanger degree control at certain of scope inside.The reinforced concrete norm isalso explicit provision:Some structure at place of dissimilarity under the condition allow existence certainthe crack of width.But at under construction should as faras possible adopt a valid measure control crack creation,make the structure don't appear crack possibly or as far aspossible decrease crack of amount and width, particularlywant to as far as possible avoid harmful crack of emergence, insure engineering quality thus.Concrete crack creation of the reason be a lot of and have already transformed to cause of crack:Such as temperaturevariety, constringency, inflation, the asymmetry sink to sink etc. reason cause of crack;Have outside carry the crack that the function cause;Protected environment not appropriate the crack etc. caused with chemical effect.Want differentiation to treat in the actual engineering, work°out a problem acco rding to the actual circumstance.In the concrete engineering the familiar crack and the prevention1.Stem Suo crack and preventionStem the Suo crack much appear after the concrete protectbe over of a period of time or concrete sprinkle to build tocomplete behind of around a week.In the cement syrup humidity of evaporate would creation stem Suo, and this kind ofconstringency is can't negative.Stem Suo crack of thecreation be main is because of concrete inside outside humidity evaporate degree dissimilarity but cause to transform dissimilarity of result:The concrete is subjected to exterior condition of influence, surface humidity losslead quick, transform bigger, inner part degree of humidityvariety smaller transform smaller, bigger surface stem theSuo transform to be subjected to concrete inner part control, creation more big pull should dint but creation crack.Therelative humidity is more low, cement syrup body stem Suo more big, stem the Suo crack be more easy creation.Stem the Suocrack is much surface parallel lines form or the net shallow thin crack, width many between 0.05-0.2 mm, the flat surface part much see in the big physical volume concrete and followit more in thinner beam plank short todistribute.Stem Suocrack usually the anti- Shen of influence concrete, cause the durable of the rust eclipse influence concrete of reinforcing bar, under the function of the water pressure dint wouldcreation the water power split crack influence concrete ofloading dint etc..Concrete stem the Suo be main with waterash of the concrete ratio, the dosage of the composition,cement of cement, gather to anticipate of the dosage of theproperty and dosage, in addition etc. relevant.Main prevention measure:While being to choose to use the constringency quantity smaller cement, general low hot water mire and powder ash from stove cement in the adoption, lower the dosage of cement.Two is a concrete of stem the Suo besubjected to water ash ratio of influence more big, water ash ratio more big, stem Suo more big, so in the concrete matchthe ratio the design should as far as possible control goodwater ash ratio of choose to use, the Chan add in the meantime accommodation of reduce water.Three is strict control concrete mix blend with under construction of match ratio,use of concrete water quantity absolute can't big in matchratio design give settle of use water quantity.Four is theearlier period which strengthen concrete to protect, andappropriate extension protect of concrete time.Winter construction want to be appropriate extension concrete heat preservation to overlay time, and Tu2 Shua protect to protect.Five is a constitution the accommodation is in theconcrete structure of the constringency sew.2.The Su constringency crack and preventionSu constringency is the concrete is before condense, surface because of lose water quicker but creation of constringency.The Su constringency crack is general at dryheat or strong wind the weather appear, crack's much presenting in the center breadth, both ends be in the centerthin and the length be different, with each other notcoherent appearance.Shorter crack general long 20-30 cm, the longer crack can reach to a 2-3 m, breadth 1-5 mm.It creationof main reason is:The concrete is eventually almost havingno strength or strength before the Ning very small, perhapsconcrete just eventually Ning but strength very hour, besubjected to heat or compare strong wind dint of influence,the concrete surface lose water to lead quick, result in inthe capillary creation bigger negative press but make a concrete physical volume sharply constringency, but at thistime the strength of concrete again can't resist its constringency, therefore creation cracked.The influence concrete Su constringency open the main factor of crack tohave water ash ratio, concrete of condense time, environment temperature, wind velocity, relative humidity...etc..Main prevention measure:One is choose to use stem the Suovalue smaller higher Huo sour salt of the earlier periodstrength or commonthe Huo sour brine mire.Two is strict the control water ash ratio, the Chan add to efficiently reducewater to increment the collapse of concrete fall a degree andwith easy, decrease cement and water of dosage.Three is tosprinkle before building concrete,water basic level and template even to soak through.Four is in time to overlay the perhaps damp grass mat of the plastics thin film,hemp slice etc., keep concrete eventually before the Ning surface ismoist, perhaps spray to protect etc. to carry on protect inthe concrete surface.Five is in the heat and strong wind the weather to want to establish to hide sun and block breezefacilities, protect in time.3.Crack and prevention that the chemical reaction causeAlkali bone's anticipating the crack that reaction crack andreinforcing bar rust eclipse cause is the most familiar inthe reinforced concrete structure of because of chemicalreaction but cause of crack.The concrete blend a future reunion creation some alkalescence ion, these ion with some activity the bone anticipate creation chemical reaction and absorb surroundings environment in of water but the physical volume enlarge, make concrete crisp loose, inflation open crack.Inthis kind of crack general emergence concrete structure usage period, once appear very difficult remediable, so should atunder construction adopt valid the measure carry onprevention.Main of prevention measure:While being to choose to anticipate with the alkali activity small freestone bone.Two is the in addition which choose to use low lye mire with low alkali or have no alkali.Three is the Chan whichchoose to use accommodation with anticipate to repress analkali bone to anticipate reaction.Because the concrete sprinkle to build, flap Dao bad perhaps is a reinforcing bar protection layer thinner, theharmful material get into concrete to make reinforcing barcreation rust eclipse, the reinforcing bar physical volumeof the rust eclipse inflation, cause concrete bulge crack,the crack of this kind type much is a crack lengthways, follow the position of reinforcing bar ually of preventmeasure from have:One is assurance reinforcing bar protection the thickness of the layer.Two is a concrete class to go together with to want good.Three is a concrete to sprinkle to note and flap Dao airtight solid.Four is a reinforcing bar surface layer Tu2 Shua antisepsis coating.Crack processingThe emergence of the crack not only would influence structure of whole with just degree, return will cause the rust eclipse of reinforcing bar, acceleration concrete ofcarbonization, lower durable and anti- of concrete tired,anti- Shen ability.Therefore according to the property ofcrack and concrete circumstance we want differentiation totreat, in time processing, with assurance building of safety usage.The repair measure of the concrete crack is main to havethe following some method:Surface repair method, infuse syrup, the Qian sew method, the structure reinforce a method, concrete displacement method, electricity chemistry protection method and imitate to living from heal method.Surface repair the method be a kind of simple, familiar of repair method, it main be applicable to stability and tostructure loading the ability don't have the surface crackof influence and deep enter crack of processing.The processing measure that is usually is a surface in crackdaubery cement syrup, the wreath oxygen gum mire or at concrete surface Tu2 Shua paint, asphalt etc. antisepsismaterial, at protection of in the meantime for keeping concrete from continue under the influence of various function to open crack, usually can adoption the surface incrack glue to stick glass fiber cloth etc. measure.1, infuse syrup, the Qian sew methodInfuse a syrup method main the concrete crack been applicable to have influence or have already defend Shenrequest to the structure whole of repair, it is make use ofpressure equipments gum knot the material press into thecrack of concrete, gum knot the material harden behind andconcrete formation one be whole,thus reinforce of purpose.The in common use gum knot material has the cementthe syrup, epoxy, A JiC Xi sour ester and gather ammonia ester to equalize to learn material.The Qian sew a method is that the crack be a kind of mostin common use method in, it usually is follow the crack digslot, the Qian fill Su in the slot or rigid water materialwith attain closing crack of purpose.The in common use Sumaterial has PVCgum mire, plastics ointment, the D Ji rubber etc.;In commonuse rigid water material is the polymer cement sand syrup.2, the structure reinforce a methodWhen the crack influence arrive concrete structure of function, will consideration adopt to reinforce a method to carry on processing to the concrete structure.The structurereinforce medium in commonuse main have the following a few method:The piece of enlargement concrete structure in everyaspect accumulate, outside the Cape department of the Goupiece pack type steel, adoption prepare should the dint method reinforce, glue to stick steel plate to reinforce,increase to establish fulcrum to reinforce and jet the concrete compensation reinforce.3, concrete displacement methodConcrete displacement method is processing severity damage concrete of a kind of valid method, this method be first will damage of the concrete pick and get rid of, then again displacement go into new of concrete or other material.Thein common use displacement material have:Common concrete orthe cement sand syrup, polymer or change sex polymer concreteor sand syrup.ConclusionThe crack is widespread in the concrete structure existence of a kind of phenomenon, it of emergence not only will lowerthe anti- Shen of building ability, influence building ofusage function, and will cause the rust eclipse of reinforcing bar, the carbonization of concrete, lower thedurable of material, influence building of loading ability,so want to carry on to the concrete crack earnest research, differentiation treat, adoption reasonable of the method carry on processing, and at under construction adopt various valid of prevention measure to prevention crack of emergence and development, assurance building and Gou piece safety,stability work.From《 CANADIAN JOURNAL OF CIVIL ENGINEERING》。

土木工程英文文献及翻译-英语论文.doc

土木工程英文文献及翻译-英语论文.doc

土木工程英文文献及翻译-英语论文土木工程英文文献及翻译in Nanjing, ChinaZhou Jin, Wu Yezheng *, Yan GangDepartment of Refrigeration and Cryogenic Engineering, School of Energy and Power Engineering, Xi’an Jiao Tong University,Xi’an , PR ChinaReceived 4 April 2005; accepted 2 October 2005Available online 1 December 2005AbstractThe bin method, as one of the well known and simple steady state methods used to predict heating and cooling energyconsumption of buildings, requires reliable and detailed bin data. Since the long term hourly temperature records are notavailable in China, there is a lack of bin weather data for study and use. In order to keep the bin method practical in China,a stochastic model using only the daily maximum and minimum temperatures to generate bin weather data was establishedand tested by applying one year of measured hourly ambient temperature data in Nanjing, China. By comparison with themeasured values, the bin weather data generated by the model shows adequate accuracy. This stochastic model can be usedto estimate the bin weather data in areas, especially in China, where the long term hourly temperature records are missingor not available.Ó 2005 Elsevier Ltd. All rights reserved.Keywords: Energy analysis; Stochastic method; Bin data; China1. IntroductionIn the sense of minimizing the life cycle cost of a building, energy analysis plays an important role in devel-oping an optimum and cost effective design of a heating or an air conditioning system for a building. Severalmodels are available for estimating energy use in buildings. These models range from simple steady state mod-els to comprehensive dynamic simulation procedures.Today, several computer programs, in which the influence of many parameters that are mainly functionsof time are taken into consideration, are available for simulating both buildings and systems and performinghour by hour energy calculations using hourly weather data. DOE-2, BLAST and TRNSYS are such* Corresponding author. Tel.: +86 29 8266 8738; fax: +86 29 8266 8725.E-mail address: yzwu@ (W. Yezheng).0196-8904/$ - see front matter Ó 2005 Elsevier Ltd. All rights reserved.doi:10.1016/NomenclatureZ. Jin et al. / Energy Conversion and Management 47 (2006) 1843–1850number of daysfrequency of normalized hourly ambient temperatureMAPE mean absolute percentage error (%)number of subintervals into which the interval [0, 1] was equally dividednumber of normalized temperatures that fall in subintervalprobability densityhourly ambient temperature (°C)normalized hourly ambient temperature (dimensionless)weighting factorSubscriptscalculated valuemeasured valuemax daily maximummin daily minimumprograms that have gained widespread acceptance as reliable estimation tools. Unfortunately, along withthe increased sophistication of these models, they have also become very complex and tedious touse [1].The steady state methods, which are also called single measure methods, require less data and provideadequate results for simple systems and applications. These methods are appropriate if the utilization ofthe building can be considered constant. Among these methods are the degree day and bin data methods.The degree-day methods are the best known and the simplest methods among the steady state models.Traditionally, the degree-day method is based on the assumption that on a long term average, the solarand internal gains will offset the heat loss when the mean daily outdoor temperature is 18.3 °C and thatthe energy consumption will be proportional to the difference between 18.3 °C and the mean daily tempera-ture. The degree-day method can estimate energy consumption very accurately if the building use and theefficiency of the HVAC equipment are sufficiently constant. However, for many applications, at least oneof the above parameters varies with time. For instance, the efficiency of a heat pump system and HVAC equip-ment may be affected directly or indirectly by outdoor temperature. In such cases, the bin method can yieldgood results for the annual energy consumption if different temperature intervals and time periods areevaluated separately. In the bin method, the energy consumption is calculated for several values of the outdoortemperature and multiplied by the number of hours in the temperature interval (bin) centered around thattemperature. Bin data is defined as the number of hours that the ambient temperature was in each of a setof equally sized intervals of ambient temperature.In the United States, the necessary bin weather data are available in the literature [2,3]. Some researchers[4–8] have developed bin weather data for other regions of the world. However, there is a lack of informationin the ASHRAE handbooks concerning the bin weather data required to perform energy calculations in build-ings in China. The practice of analysis of weather data for the design of HVAC systems and energy consump-tion predictions in China is quite new. For a long time, only the daily value of meteorological elements, such asdaily maximum, minimum and average temperature, was recorded and available in most meteorologicalobservations in China, but what was needed to obtain the bin weather data, such as temperature bin data,were the long term hourly values of air temperature. The study of bin weather data is very limited in China.Only a few attempts [9,10] in which bin weather data for several cities was given have been found in China.Obviously, this cannot meet the need for actual use and research. So, there is an urgent need for developing binweather data in China. The objective of this paper, therefore, is to study the hourly measured air temperaturedistribution and then to establish a model to generate bin weather data for the long term daily temperaturedata.2. Data usedZ. Jin et al. / Energy Conversion and Management 47 (2006) 1843–1850In this paper, to study the hourly ambient temperature variation and to establish and evaluate the model, aone year long hourly ambient temperature record for Nanjing in 2002 was used in the study. These data aretaken from the Climatological Center of Lukou Airport in Nanjing, which is located in the southeast of China(latitude 32.0°N, longitude 118.8°E, altitude 9 m).In addition, in order to create the bin weather data for Nanjing, typical weather year data was needed.Based on the long term meteorological data from 1961 to 1989 obtained from the China MeteorologicalAdministration, the typical weather year data for most cities in China has been studied in our former research[11] by means of the TMY (Typical Meteorological Year) method. The typical weather year for Nanjing isshown in Table 1. As only daily values of the meteorological elements were recorded and available in China,the data contained in the typical weather year data was also only daily values. In this study, the daily maxi-mum and minimum ambient temperature in the typical weather year data for Nanjing was used.3. Stochastic model to generate bin dataTraditionally, the generation of bin weather data needs long term hourly ambient temperature records.However, in the generation, the time information, namely the exact time that such a temperature occurredin a day, was omitted, and only the numerical value of the temperature was used. So, the value of each hourlyambient temperature can be treated as the independent random variable, and its distribution within the dailytemperature range can be analyzed by means of probability theory.3.1. Probability distribution of normalized hourly ambient temperatureSince the daily maximum and minimum temperatures and temperature range varied day by day, the con-cept of normalized hourly ambient temperature should be introduced to transform the hourly temperatures ineach day into a uniform scale. The new variable, normalized hourly ambient temperature is defined by^ ¼ttmintmaxtminwhere ^ may be termed the normalized hourly ambient temperature, tmaxand tminare the daily maximum andminimum temperatures, respectively, t is the hourly ambient temperature. Obviously, the normalized hourly ambient temperature ^ is a random variable that lies in the interval [0, 1].To analyze its distribution, the interval [0, 1] can be divided equally into several subintervals, and by means ofthe histogram method [12]iin each subinterval can be calculated by1137土木工程英文文献及翻译Based on the one year long hourly ambient temperature data in Nanjing, China, the probability density piwas calculated for the whole day and the 08:00–20:00 period, where the interval [0, 1] was equally divided into50 subintervals, namely n equals 50. The results are shown in Fig. 1.According to the discrete probability density data in Fig. 1, the probability density function of ^ can beobtained by a fitting method. In this study, the quadratic polynomialswere used to fit the probability density data, where a, b and c are coefficients. According to the property of theprobability density function, the following equation should be satisfiedAs shown in Fig. 1, the probability density curve obtained according to the probability density data pointsis also shown. The probability densit y functions that are fitted are described byp ¼ 2:7893^23:1228^ þ 1:6316 for the whole day periodp ¼ 2:2173^20:1827^ þ 0:3522 for the 08 : 00–20 : 00 period3.2. The generation of hourly ambient temperatureAs stated in the beginning of this paper, the objective of this study is to generate the hourly ambient tem-perature needed for bin weather data generation in the case that only the daily maximum and minimum tem-peratures are known. To do this, we can use the obtained probability density function to generate thenormalized hourly ambient temperature and then transform it to hourly temperature. This belongs to theproblem of how to simulate a random variable with a prescribed probability density function and can be doneon a computer by the method described in the literature [13]. For a given probability density function f ð^Þ, ifits distribution function F ð^Þ can be obtained and if u is a random variable with uniform distribution on [0, 1],thenF, we need only setAs stated above, the probability density function of the normalized ambient temperature was fitted using aone year long hourly temperature data. Based on the probability density function obtained, the random nor-malized hourly temperature can be generated. When the daily maximum and minimum temperature areknown, the normalized hourly temperature can be transformed to an actual temperature by the followingequationWhen the hourly temperature for a particular period of the day has been generated using the above method,the bin data can also be obtained. Because the normalized temperature generated using the model in this studyis a random variable, the bin data obtained from each generation shows somedifference, but it has much sim-ilarity. To obtain a stable result of bin data, the generation of the bin data can be performed enough times,and the bin data can be obtained by averaging the result of each generation. In this paper, 50 generations wereaveraged to generate the bin weather data.Z. Jin et al. / Energy Conversion and Management 47 (2006) 1843–18503.4. Methods of model evaluationThe performance of the model was evaluated in terms of the following statistical error test:土木工程英文文献及翻译一种产生bin气象数据的随机方法——中国南京周晋摘要:bin方法是一种众所周知且简捷的稳态的计算方法,可以用来预计建筑的冷热能耗。

土木工程毕业设计英文翻译论文

土木工程毕业设计英文翻译论文

Structural FormsStructural forms, such as the beam or the arch ,have developed through the ages in relation to the availability of materials and the technology of the time. The arch, for instance, undoubtedly developed as a result of the availability of brick. In the technology of buildings .every structure must work against gravity ,which tends to pull everything down to the ground .A balance must therefore be attained between the force of gravity ,the shape of the structure ,and the strength of the material used. To provide a cover over a sheltered space and permit openings in the walls that surround it ,builders have developed four techniques are post and lintel, arch and vault, truss, and cantilever construction.Post and lintel. In post and lintel construction ,a horizontal beam is placed across the space between two supporting posts. If the support is continuous, it is called a wall; if a series of beams are joined together into a continuous surface, it is called a slab.Simple rectilinear buildings result from post and lintel construction, which is characteristic of much primitive construction as well as of the classical Greek temples. In this type of construction, the post (or column) carries only a vertical weight, or load, and is therefore under compression, and the lintel (or beam) is bent by the loads acting transversely to its axis. Therefore , the post must have compressive strength, and the beam must have bending strength. Both wood and stone were used in early example of this type of construction , although the limited bending strength of stone dictated the close column spacing which is apparent in Greek temples. For example, in the Parthenon in Athens, the space between the columns is approximately equal to the column diameter.Modern building materials such as steel and reinforced concrete are used to advantage in post and lintel construction. The skeleton frame of a modern steel skyscraper, for instance, consists of beams and columns in a three-dimensional post and lintel network, or grid. The typical wood fame house, with closely spaced wooden post, or studs, and floors with a series of closely spaced wood beams, or joists, also illustrates post and lintel construction.Just as a house of cards can support vertical loads but collapses under a slightbreath of air, the post and lintel system can topple under winds or earthquakes, but of which impose a horizontal force. This collapse is due to the fact that the joint between the column and beam acts as if it were a hinge .In earlier times this lateral instability was not apparent because the weight and the mass of the materials (particularly stone) and the limited height of the structures negated the importance of horizontal forces. In tall modern building that have slender elements made of strong and light materials such as steel, lateral instability becomes a significant factor . To provide the necessary lateral resistance, a rigid connection must be made between the vertical column and horizontal beam. This creates a rigid frame; it is used to achieve lateral stability in skyscraper construction.Arch. The arch which is characteristically a masonry type of construction, undoubtedly had its origin in Mesopotamia,a land of brick buildings. Arches consist of masonry blocks in the form of a curved line. In principle, each wedge-shaped masonry block cannot fall inward without pushing the others out ;thus, the whole arch form remains stable as long as a force is applied at the base to keep it from spreading. This force is called a horizontal thrust. A continuous series of arches is known as a vault.The Etruscans, by their examples of arch constructions in bridges and gates, probably inspired the Roman to experiment with this type of construction about 600 B.C. However, it was not until the last years of the Roman republic that tunnel vaults and intersecting, or groined, vaults were used to cover large rooms. The form of the Roman arch or vault is generally semicircular for reasons of geometric simplicity. As a result, all wedge-shaped stones are identical; their curved edges are equidistant from the center of the circle ,and their straight edges lie on equally spaced lines radiating from the center. This type of semicircular arch was widely used by the Romans in buildings such as the Basilica of Constantine and the Baths of Caracalla and in gates such as the Porta Maggiore in Rome.The Gothic arch, which is characterized by its pointed shape ,evolved in France in the 12th century. This form characterizes some of the most magnificent churches of the early Renaissance period such as the Chartres. Amiens, and Rheims cathedral. theform of the Gothic arch is superior to the Roman arch because of its greater structural clarity, which closely approaches the shapes the shape of an idea arch. The concept of the idea arch can best be explained by a comparison with a suspension cable.A chain or a cable supported at each end assumes a curved shape called a catenary (from catena, chain).If the cable were required to support one weight hung from it ,it would change shape to adjust to this condition ;this is due to the fact that a cable carries loads only by the actin of simple tension along the length of the cable. If, instead of a single load, many parabola. The catenary and the parabola are geomertrically similar since the weight of the cable is approximately a uniformly distributed load .An ideal arch may be thought of as a cable frozen in its shape and turned upside down.(Instead of carrying loads by tension, as in the cable, the ideal arch carries loads by simple compression)This ideal shape of load the arch is called the “funicular curve” A different funicular curve exists for every type of load the arch is required to carry. Since the arch ,unlike the flexible cable ,cannot adjust its shape to the load ,then the arch, under a load other than that which gave it its funicular shape, must also carry the load by bending, as in a beam .The structural efficiency of an arch can thus be measured in terms of the proximity of the geometric shape to the funicular curve ,In the semicircular Romans arch ,there is a large difference between the funicular curve of the loads and the circular shape. The pointed Gothic arches are much closer to the funicular curve of the loads and therefore possess a clear advantage over the earlier semicircular form.To resist the horizontal thrust which exists at the base of an arch ,the Roman used massive piers or buttresses. In some of the Gothic cathedrals, which raised the arch high above the nave, flying buttresses over the side aisles were used to counteract the thrust.In modern times ,arch construction has been used extensively for bridge, utilizing steel, wood, or reinforced concrete. The concrete arch bridges built by Robert Maillart in Switzerland are outstanding examples of elegance and structural clarity in modern arch design.Truss. The simplest form of truss is a triangle consisting of three bars. Thiselementary truss form undoubtedly grew out of the use of the gabled roof for small houses and churches. In this construction, two slanting rafters rest on top of a wall and are pinned at the peak. The load of the roof tends to push out the top of the walls. Tying the bottom of the rafters together with a bar or rod counters this outward push. The resulting triangular shape is a rigid form geometrically, because none of its angles can change without changing the length of its sides. Each element in a truss is subject to either tension or compression; in the simple triangular truss, the rafters are in compression and the tie rod is in tension.The elementary triangular truss is limited to spanning relatively short distance because each slanting member is long compared to the span. In a triangular truss with equal angles, for instance, each member is as long as the span. This drawback was recognized by Andrea Palladio in the 16th century. His design for a trussed bridge utilized the principle that if a single triangles is rigid ,combinations of triangles are also rigid . By arranging short lengths of timbers in a series of triangles to form complex trusses, almost any distance can be spanned.It was not until the 19th century , when mathematical methods of analysis became known and iron and steel were introduced, that trusses with a great degree of perfection and elegance were developed. Modern trusses with a variety of configurations are used to span auditoriums, armories, and convention halls , creating large column-free spaces. The type of trusses most commonly used in buildings are the Pratt, Howe, and Warren trusses, all named after their inventors. The Pratt and Howe trusses have top and bottom chords (horizontal elements), and both verticals and diagonals between the chords. The Warren truss has only diagonals joining the top and bottom chord .Cantilever. In cantilever construction, building elements are projected outward from a fixed support. An early kind of cantilever construction was the corbel; it had its origin in the late Stone Age and can be found in the form of corbelled domes built in Sarrdinia about 2,500 B.C. In corbel construction, each successive layer of stone stands out farther from a wall in the form of upside-down steps. Only the weight of the stones above and behind the face of the wall prevent a corbel from collapsing. Anexcessive amount of material is required for corbel construction because of the necessity for heavy masonry walls.Cantilevering building elements from a wall or other fixed support permits projecting part of a building beyond the ground-level construction to gain more living area above, as in many of the Renaissance town houses.The cantilever is much used in modern buildings as a result of the availability of steel and reinforced concrete. It is a simple matter in a concrete apartment building to create a cantilevered balcony when the balcony slab is merely a continuation of the interior slab. The Kaumfman house, built by Frank Lloyd Wright in 1939, is an example of a dramatic use of cantilevers and demonstrates the potential of this type of construction. In a steel-framed building, beams can project beyond column to permit the face of the building to be a curtain wall with large glass areas. This cantilever construction was exemplified by the Bauhaus (1926) ,which was used as a model for many skyscrapers built after World WarⅡ结构形式结构形式,如梁或拱,通过发展有关的材料供应和当时的技术的年龄。

土木工程专业英语论文

土木工程专业英语论文

Take the road of sustainable development civil engineeringAbstract: Civil Engineering is the oldest in human history "technical science" as a system of industrial activity, the essence of civil engineering production process, is a technical process摘要:土木工程是人类历史上年代最久远的“技术科学”,作为一种系统的产业活动,土木工程的实质是生产的过程,是一种技术过程。

Civil engineering is the construction of various facilities in science and technology, collectively, both refer to the construction of the object, that is built on the ground, underground, water facilities, a variety of projects, but also refers to the application of materials, equipment and carried out survey and design , construction, maintenance, repair and other technology.As an important basis for discipline, civil engineering has its important attributes: a comprehensive, social, practical, technical and economic and artistic unity. With the progress of human society and development, civil engineering has already evolved into large-scale comprehensive subject, and has many branches, such as: construction, railroad engineering, road engineering, bridge engineering, specialty engineering structures, water supply and drainage projects, port engineering, hydraulic engineering, environmental engineering and other disciplines. There are six professional civil engineering: architecture, urban planning, civil engineering, built environment and equipment engineering, water supply and drainage works and road and bridge projects. Introduction to Engineering through a semester course of study, I have been deeply impressed by the Civil Engineering covers a wide range, appreciate the achievements of their predecessors, but also understand that as a civil engineer of great responsibility. Of course, we can not have been immersed in the brilliant achievements, stalled. We should also advance with the times, to dig, to discover, to think, to imagine, to be innovative. In this, China's future as a civil engineer, I would like to combine the history of civil engineering, combined with China's national conditions and the world situation, to talk about civil engineering and sustainable development.My knowledge about civil engineering has been broadened since I became a student of Tongji University.Civil engineering is a form of human activity. Human beings pursued it to change the natural environment for their own benefit. Buildings, transportations, facilities, infrastructures are all included in civil engineering.The development of civil engineering has a long history. Our seniors had left a lot of great constructions to us. For example, Zhao Zhou Bridge is the representative of our Chinese civil engineering masterpieces. It has a history of more than 1300 years and is still service at present. Civil engineering has been so rapid development of the period. A lot of new bridges have been constructed, and many greater plans are under discussion. China is a large county. And she is still well developing. So this era will be both exciting and rewarding for the Chinese Civil Engineers. And of course, civil engineering’s futu re is promising.However, civil engineers will be facing more complex problems. We should pay attention to the growing population and a lot of deteriorating infrastructures. We should prepare for the possibility of natural disasters. To meet grow needs in the future; we should also try to update all the transportation systems.To deal with these problems, we will have to develop innovative and enterprising skills. And we should choose a way that we can go continuously. Hazard Mitigation may be a great choice. Not only can it save money in the long run, but also avoid getting into an embarrassing situation in which we have to rebuild all the broken buildings. And we should also use more environmentally friendly materials when designing or constructing new buildings.Well, to be a brilliant civil engineer is not easy. Today, engineering is a synthetic system. It not only depends on traditional mechanics, but also closely related to advanced science. So Physics, Chemistry, Material Science, Computer Science and perhaps more are all in our civil engineering program.To be a good civil engineer, we should have the ability to apply the knowledge, to design a system, a component, or a procedure of construction. We should also be able to conduct experiments and explain the results. Furthermore, an engineer never works alone, so we shall cooperate with working team, and try our best to communicate effectively.I’m very glad to be a student in this wonderful field. And I will try my best to be a successful civil engineer, to make contributions to our motherland.1. Of civil engineering history, current situation and future development of knowledge 1.1.1 Ancient Civil EngineeringAncient Civil Engineering has a very long time span, it is roughly from 5000 BC to the Neolithic Age to the mid-17th century, around about 7000 years. In housing construction, bridge engineering, hydraulic engineering, tower engineering have made brilliant achievements. Some of the masterpieces of ancient civilization handed down a lot, so far stand tall. For example, China's Great Wall, Egyptian pyramids and so on. Built in the 6th century arch bridge, is the world's first open shoulder arch bridge, in 1991, American Society of Civil Engineers was selected as the world in 12 civil engineering landmark. 1.1.2 Modern Civil EngineeringThe time span of the modern civil engineering from the mid-17th century to the mid-20th century, after about 300 years. In the meantime, construction materials mainly from a shift to natural materials mainly man-made materials, the construction of theory building from the main to sum up the experience long-term experience to take into account the importance of scientific change. Construction techniques, some of the performance of large machinery along with a variety of highly effective methods of construction there, so people began to construct the complex structure or a poor environment in which civil engineering. During the completion of the Eiffel Tower, Empire State Building and Golden Gate suspension bridge, is still regarded as the great civil engineering.1.1.3 Modern Civil EngineeringModern civil engineering began in the mid-20th century. Development to date,civil engineering in building materials, structural theory and constructiontechniques have made very great progress.Building materials, high-strength concrete, high strength low alloy steel,polymers, glass more and more appear in the buildings. Structure theory, theuse of powerful computing and computer graphics, mechanical analysis and theresults more in line with the results of the calculation of the actual situation inwhich the design is more reliable. For building technology, have been developedto machine - electrical - computer integration, the construction process, whetherit is God, and crosses into the earth or the sea, are not the construction of thebarrier; and the widespread use of welding technology, but also makes the steelstructure development has entered a new stage.Created by world-renowned modern civil engineering construction are: China'sTaipei International Financial Center, Shanghai Jin Mao T ower, Kuala Lumpur,Malaysia's oil and building the twin towers, the French Normandy cable-stayedbridge and so on.1.2 pairs of understanding of the status of civil engineeringToday's civil engineering, are increasingly using the same function or itsproduction process closely.Requirements of public and residential buildings in the architectural, structural,water supply and drainage, heating, ventilation for gas, electricity and othermodern technical equipment increasingly integrated as a whole.Industrial buildings require constant temperature and humidity, anti-vibration,anti-corrosion, radiation, fire, explosion, magnetic, dust, high (low) temperature,resistance to high (low) wet, to a large span, ultra-heavy-duty, flexible spacedirection.In addition, a growing number of high-rise buildings, underground engineeringhigh-speed development, urban elevated highways, overpasses appeared inlarge numbers, and the progressive realization of high-speed transportation,large-scale water conservancy projects.It is worth mentioning that China's reform and opening up, the comprehensivenational strength has greatly improved, and already has more large-scaledevelopment and use of water conditions, such as the Three Gorges Dam,water diversion project are all world-class large-scale water project.1.3 pairs of understanding the future development of Civil EngineeringWith the constant deepening of China's reform and opening up and rapideconomic development, China will face a more massive building boom. We cansay that we are faced with a leap of civil engineering along with the greatdevelopment of the national economy a good period. And such a gooddevelopment environment has been and will continue to be the West's urgentattention.As a cross-century generation, this situation provides us with excellent rareShizhancaigan unprecedented, the impact to the international standards of goodopportunities. At the same time, we feel deeply that this is an "opportunity" and"challenge" coexist, "cooperation" and "competition" intertwined, "innovation"and "follow the old" era of competing, how to grasp the turn of the century whenthe Civil disciplines, trends, and create with Chinese characteristics, world-classnew era of civil engineering disciplines, a generation of our century's challenges.2. My feelings and understanding: China's Civil Engineering to go the road of sustainabledevelopmentChina's civil engineering has its own particularity."China is the world's most populous country, a great resource in addition to that by 13 $ 110 to become negligible, while a small problem multiplied by 1.3 billion becomes a big problem." Professor Liu Xila this language effectively tells our the difficulty lies.China's coal, oil, gas, water, forests are living in the world total, and per capita, but all below the world average. Population, energy, education, pollution problems have become severe problems faced by the four. Path of sustainable development is imminent. And civil engineering, also will be when a long-term, out of a sustainable development.World, the modernization process of the United States can be described as advanced, and now data indicate that: the future of the United States to invest $ 1.6 trillion construction projects to address the unsafe condition, for example, chloride-induced corrosion of buildings and so on. As a contemporary civil engineer, in the tradition of the brilliant achievements of our predecessors, but also have a lot of the lessons learned have been an accident, in future work to improve innovation and achieve sustainable development.2.1 the development of high-tech, structural health monitoring applications, toachieve sustainable developmentCivil Engineering in actual use, there will be varying degrees of damage orperformance degradation, since this will affect the carrying capacity anddurability, and even lead to serious construction accidents, caused significantcasualties and economic losses, resulting in serious social impact . Therefore,from the moment of completion of construction, we must make health monitoring,repair and reinforcement of the preparation.With modern sensor technology, computer and communications technology,signal processing techniques and structural analysis and dynamic analysis ofthe rapid development of the theory, it is proposed the concept of structuralhealth monitoring, to revolutionize the development of civil engineering changes.Structural health monitoring system installed in the structure through a variety ofsensors, automatic, real-time measurement of the structure of the environment,load, response, etc., on the structure of health status assessment, scientific andeffective conservation and management structure to provide basis for decisionmaking, to ensure the structural safety of the operation to extend the structurallife.In recent years, large-scale civil engineering structures, especially large-spanbridge health monitoring domestic and international engineering and technologyas the focus of attention in the academic community through research andengineering and technical personnel research efforts have yielded fruitful results.Home and abroad in recent years, new bridges were installed in many largestructural health monitoring systems, such as China's Shanghai Xupu Bridge,Jiangyin Yangtze River Highway Bridge, the Donghai Bridge, Hong Kong's TsingMa Bridge, the bridge and Youngjong Korea Seohae bridge, U.S. CommodoreBarry Bridge and Canada Confedration bridges.Like this, through the development of structural health monitoring and safetywarning, the first time found that the construction problems that may arise,timely repair and reinforcement, both to avoid the possible constructionaccidents, construction has been largely solved the rapid aging of damage, haveRemove the restoration of the embarrassing situation, and the resulting largenumber of economic resources, a waste of time to achieve the sustainabledevelopment of building use.2.2 The rational use of natural resources, focusing on re-use of existing civilengineering infrastructure, to achieve sustainable development"Sustainable development is achieved without sacrificing the ability of futuregenerations to meet their needs and conditions, to meet current needs."Rational use of natural resources, will have in the civil engineering construction,use and maintenance process, the civil engineer to take the initiative to besaving energy, and maximize the role of both civil engineering facilities.For example, we can take advantage of building green, gray brick walls in thesummer, reduce the surface temperature, thereby reducing air conditioning use;can use energy-saving type of brick or insulation composite wall as the wallmaterial, to the role of thermal insulation in winter ; also solar energy, groundheat and other new energy sources, reducing the amount of non-renewableresources to reduce.In addition, the reuse of existing buildings is also an important means ofsustainable development. This regard, Shanghai has made a lot of successfulexperience: do not plant a lot, a lot has been transformed into exhibition halls,offices, artists studios. This transformation of re-use, consistent with therequirements of modern use, but also save energy, avoid waste, is an effective 2.3 Development and utilization of renewable resources and green resources toachieve sustainable developmentRemoval of waste each year the world of concrete, concrete waste generated byconstruction etc will have a huge amount of construction waste. China's annualconstruction of the building construction waste generated by 4,000 tons, haveproduced 13.6 million tons of waste concrete, removal processing a largeamount of environmental pollution. In addition, China is the world's cementproduction 20 years of superpower, which in itself is a high consumption ofresources, high energy consumption, pollution of the environment industry.Compared with other materials, steel and recycled concrete is more in line withgreen building standards, this should be to develop the green building materials.In this regard, Japan's Aichi World Expo, give us a vivid lesson: materials, theExpo will be a variety of construction materials on the surface is very high, butmany are recycling. Many plank wood construction waste by processing, placedaround the chair, TV cabinet is made of crush. Toyota Pavilion wall is made fromrecycled waste paper processing, long-term venue Japan Pavilion, only thepursuit of harmony between man and nature, but also saves the expenditure,the use of most of the steel and wood, can be recycled. At the same time, theadvantages of bamboo wall to September 3 Aichi summer also showedexhaustive. Bamboo greatly reduces the performance of their indoortemperature, air-conditioning use is also significantly reduced. This gave me anumber of thought: in the building material selection, the appropriate place in theapplication of renewable natural resources, save money, but also to achieve aharmonious and sustainable ecological development and architecture, why not?In addition, the World Expo in Aichi Japan Nagakute, Japan Pavilion cocoon-likein order to reduce heat load, the use of green walls, bio-degradable plasticmaterials and thinning wood (forest wood to be cut fine) to achieve theenvironmental protection function. "Nature's Wisdom" as the theme of the AichiWorld Expo, pavilion building large-scale application of modern scientific andtechnological achievements, highlighting the environmental and functional,reflecting the natural beauty of the human diligently pursuing. This should alsobe the future civil engineers to learn and develop.China's building, Professor Li Guohao Yangpu Bridge is also designed classic.Approach part of the spiral structure, saving several hundred million RMB, is acivil and sustainable economic development model.Of course, sustainable development, by no means blind pursuit of savings, butthe most reasonable to seek a middle state, we must ensure there is enoughcreative architecture, but also the pursuit of the perfect technical and economicindicators, with minimum investment for maximum benefits. We still still want tocreate classic, but must not be built on the squandering of money, based onconsuming more resources and energy basis. T oday, building the world hasentered an era of eco-aesthetics, focusing on culture, ecology, engineering andenvironmental relationship between the human-oriented, energy saving andsustainable development, the focus is the direction of contemporary engineers.3.Civil Engineering expertise should have the qualityA good civil engineer, must have the "four elements", that is, knowledge structure,practical skills, ability to structure and the overall quality and innovation.Knowledge structure, including: public basic knowledge, professional knowledge and expertise.First, the good civil engineer must have a solid basic knowledge of the public, and, in the familiar basis of natural science, a good psychological and moral humanities, social science-based knowledge is also essential.Second, the best engineers must also have excellent professional knowledge. Ofengineering mathematics, fluid mechanics, geotechnical engineering, structural engineering and so have a solid understanding and ability to apply strong.Third, also in-depth expertise. Whether engaged in railway engineering, tunnels, underground works or construction projects, each engineer has to be advanced for the emphasis on industry expertise. The only way to make our civil engineering business, walking in the forefront of the world.Inseparable from the practice of Civil Engineering. Therefore, engineers have to have superb practical skills. For example: drawing skills, computer application skills, measurement skills and structural engineering testing skills.As a Civil Engineering undergraduate students, I will be four years of college learning process, and strive to master the computer language and programming skills, treasure every opportunity to practice on the machine, and in college physics experiments, material testing and structural experiments The general structure of the experiment to master the basic method, with the structure of the initial test of skills, and providing technical training, curriculum design, structural design for the contest winners.In addition, the difference between engineers and scientists not only by the constraints of the laws of nature, will be bound by the laws of society. Engineering and technical personnel complete each project is a program of "social activities" may not rely on a person in the room alone. Therefore, to have sufficient capacity to deal with social, follow the laws of good society.In school life, I will continue to improve their learning ability, from the engineering capabilities to enhance learning, students work to enhance the management capacity, and gradually improve their own knowledge structure, from which to develop a science and technology development capabilities and skills and the ability of public relations to do more.However, these skills also help to constitute a truly sustainable development of China's civil engineer. Because the engineer is the most important cultural enrichment with high moral and intellectual quality. In order to state and national interests, dedicated to the cause of the motherland. For the country's honor, to have a strong sense of competition. With dialectical materialist way of thinking, there is step on solid, rigorous, hard working style. The only way to be a qualified civil engineer in China.We should also note that China's civil engineering industry with world-class level there is a gap. For example, many domestic high-rise buildings (including the Shanghai World Financial Center), almost all of its engineering design borne from abroad, almost all steel products imported from abroad, the general contractor were mostly borne by the foreign countries, only the steel structure fabrication and installation work by domestic unit commitment. Be completely independent intellectual property rights, engineering and construction to achieve the localization, catch up with international standards, we need the young generation to complete!附录:参考资料:《土木工程》(英)斯科特(Scott,J.S.)撰中国建筑工业出版社《土木建筑文献检索与利用》肖友瑟主编大连理工大学出版社《土木工程总论》丁大钧,蒋永生编中国建筑工业出版社《土木建筑工程概论》王继明主编高等教育出版社《土木工程学报》中国土木工程学会土木工程学报编辑部《土木工程》中国土木工程学会科学出版社《土木工程概论》上海交通出版社《土木系统工程》机械工业出版社《INTRODUCTION OF CIVIL ENGINEERING》中国建筑工业出版社。

【设计】土木工程毕业设计英语论文及翻译

【设计】土木工程毕业设计英语论文及翻译

【关键字】设计土木工程毕业设计英语论文及翻译篇一:土木工程毕业设计外文文献翻译外文文献翻译Reinforced ConcreteConcrete and reinforced concrete are used as building materials in every country. In many, including the United States and Canada, reinforced concrete is a dominant structural material in engineered construction. The universal nature of reinforced concrete construction stems from the wide availability of reinforcing bars and the constituents of concrete, gravel, sand, and cement, the relatively simple skills required in concrete construction, and the economy of reinforced concrete compared to other forms of construction. Concrete and reinforced concrete are used in bridges, buildings of all sorts underground structures, water tanks, television towers, offshore oil exploration and production structures, dams, and even in ships.Reinforced concrete structures may be cast-in-place concrete, constructed in their final location, or they may be precast concrete produced in a factory and erected at the construction site. Concrete structures may be severe and functional in design, or the shape and layout and be whimsical and artistic. Few other building materials off the architect and engineer such versatility and scope.Concrete is strong in compression but weak in tension. As a result, cracks develop whenever loads, or restrained shrinkage of temperature changes, give rise to tensile stresses in excess of the tensile strength of the concrete. In a plain concrete beam, the moments about the neutral axis due to applied loads are resisted by an internal tension-compression couple involving tension in the concrete. Such a beam fails very suddenly and completely when the first crack forms. In a reinforced concrete beam, steel bars are embedded in the concrete in such a way that the tension forces needed for moment equilibrium after the concrete cracks can be developed in the bars.The construction of a reinforced concrete member involves building a from of mold in the shape of the member being built. The form must be strong enough to support both the weight and hydrostatic pressure of the wet concrete, and any forces applied to it by workers, concrete buggies, wind, and so on. The reinforcement is placed in this form and held in place during the concreting operation. After the concrete has hardened, the forms are removed. As the forms are removed, props of shores are installed to support the weight of the concrete until it has reached sufficient strength to support the loads by itself.The designer must proportion a concrete member for adequate strength to resist the loads and adequate stiffness to prevent excessive deflections. In beam must be proportioned so that it can be constructed. For example, the reinforcement must be detailed so that it can be assembled in the field, and since the concrete is placed in the form after the reinforcement is in place, theconcrete must be able to flow around, between, and past the reinforcement to fill all parts of the form completely.The choice of whether a structure should be built of concrete, steel, masoy, or timber depends on the availability of materials and on a number of value decisions. The choice of structural system is made by the architect of engineer early in the design, based on the following considerations:1. Economy. Frequently, the foremost consideration is the overall const of the structure. This is, of course, a function of the costs of the materials and the labor necessary to erect them. Frequently, however, the overall cost is affected as much or more by the overall construction time since the contractor and owner must borrow or otherwise allocate money to carry out the construction and will not receive a return on this investment until the building is ready for occupancy. In a typical large apartment of commercial project, the cost of construction financing will be a significant fraction of the total cost. As a result, financial savings due to rapid construction may more than offset increased material costs. For this reason, any measures the designer can take to standardize the design and forming will generally pay off in reduced overall costs.In many cases the long-term economy of the structure may be more important than the first cost. As a result, maintenance and durability are important consideration.2. Suitability of material for architectural and structural function.A reinforced concrete system frequently allows the designer to combine the architectural and structural functions. Concrete has the advantage that it is placed in a plastic condition and is given the desired shapeand texture by means of the forms and the finishing techniques. This allows such elements ad flat plates or other types of slabs to serve as load-bearing elements while providing the finished floor and / or ceiling surfaces. Similarly, reinforced concrete walls can provide architecturally attractive surfaces in addition to having the ability to resist gravity, wind, or seismic loads. Finally, the choice of size of shape is governed by the designer and not by the availability of standard manufactured members.3. Fire resistance. The structure in a building must withstand the effects of a fire and remain standing while the building is evacuated and the fire is extinguished. A concrete building inherently has a 1- to 3-hour fire rating without special fireproofing or other details. Structural steel or timber buildings must be fireproofed to attain similar fire ratings.4. Low maintenance. Concrete members inherently require less maintenance than do structural steel or timber members. This is particularly true if dense, air-entrained concrete has been used for surfaces exposed to the atmosphere, and if care has been taken in the design to provide adequate drainage off and away from the structure. Special precautions must be taken for concrete exposed to salts such as deicing chemicals.5. Availability of materials. Sand, gravel, cement, and concrete mixing facilities are verywidely available, and reinforcing steel can be transported to most job sites more easily than can structural steel. As a result, reinforced concrete is frequently used in remote areas.On the other hand, there are a number of factors that may cause one to select a material other than reinforced concrete. These include:1. Low tensile strength. The tensile strength concrete is much lower than its compressive strength ( about 1/10 ), and hence concrete is subject to cracking. In structural uses this is overcome by using reinforcement to carry tensile forces and limit crack widths to within acceptable values. Unless care is taken in design and construction, however, these cracks may be unsightly or may allow penetration of water. When this occurs, water or chemicals such as road deicing salts may cause deterioration or staining of the concrete. Special design details are required in such cases. In the case of water-retaining structures, special details and / of prestressing are required to prevent leakage.2. Forms and shoring. The construction of a cast-in-place structure involves three steps not encountered in the construction of steel or timber structures. These are ( a ) the construction of the forms, ( b ) the removal of these forms, and (c) propping or shoring the new concrete to support its weight until its strength is adequate. Each of these steps involves labor and / or materials, which are not necessary with other forms of construction.3. Relatively low strength per unit of weight for volume. The compressive strength of concrete is roughly 5 to 10% that of steel, while its unit density is roughly 30% that of steel. As a result, a concrete structure requires a larger volume and a greater weight of material than does a comparable steel structure. As a result, long-span structures are often built from steel.4. Time-dependent volume changes. Both concrete and steel undergo-approximately the same amount of thermal expansion and contraction. Because there is less mass of steel to be heated or cooled, and because steel is a better concrete, a steel structure is generally affected by temperature changes to a greater extent than is a concrete structure. On the other hand, concrete undergoes frying shrinkage, which, if restrained, may cause deflections or cracking. Furthermore, deflections will tend to increase with time, possibly doubling, due to creep of the concrete under sustained loads.In almost every branch of civil engineering and architecture extensive use is made of reinforced concrete for structures and foundations. Engineers and architects requires basic knowledge of reinforced concrete design throughout their professional careers. Much of this text is directly concerned with the behavior and proportioning of components that make up typical reinforced concrete structures-beams, columns, and slabs. Once the behavior of these individual elements is understood, the designer will have the background to analyze and design a wide range of complex structures, such as foundations, buildings, and bridges, composed of these elements.Since reinforced concrete is a no homogeneous material that creeps, shrinks, and cracks, its stresses cannot be accurately predicted by the traditional equations derived in a course instrength of materials forhomogeneous elastic materials. Much of reinforced concrete design in therefore empirical, i.e., design equations and design methods are based on experimental and time-proved results instead of being derived exclusively from theoretical formulations.A thorough understanding of the behavior of reinforced concrete will allow the designer to convert an otherwise brittle material into tough ductile structural elements and thereby take advantage of concrete’s desirable characteristics, its high compressive strength, its fire resistance, and its durability.Concrete, a stone like material, is made by mixing cement, water, fine aggregate ( often sand ), coarse aggregate, and frequently other additives ( that modify properties ) into a workable mixture. In its unhardened or plastic state, concrete can be placed in forms to produce a large variety of structural elements. Although the hardened concrete by itself, i.e., without any reinforcement, is strong in compression, it lacks tensile strength and therefore cracks easily. Because ueinforced concrete is brittle, it cannot undergo large deformations under load and fails suddenly-without warning. The addition fo steel reinforcement to the concrete reduces the negative effects of its two principal inherent weaknesses, its susceptibility to cracking and its brittleness. When the reinforcement is strongly bonded to the concrete, a strong, stiff, and ductile construction material is produced. This material, called reinforced concrete, is used extensively to construct foundations, structural frames, storage takes, shell roofs, highways, walls, dams, canals, and innumerable other structures and building products. Two other characteristics of concrete that are present even when concrete is reinforced are shrinkage and creep, but the negative effects of these properties can be mitigated by careful design.A code is a set technical specifications and standards that control important details of design and construction. The purpose of codes it produce structures so that the public will be protected from poor of inadequate and construction.Two types f coeds exist. One type, called a structural code, is originated and controlled by specialists who are concerned with the proper use of a specific material or who are involved with the safe design of a particular class of structures.篇二:土木工程毕业设计中英文翻译附录:中英文翻译英文部分:LOADSLoads that act on structures are usually classified as dead loads or live loads.Dead loads are fixed in location and constant in magnitude throughout the life of the ually the self-weight of a structure is the most important part of the structure and the unit weight of the material.Concrete density varies from about 90 to 120 pcf (14 to 19 KN/m2)for lightweight concrete,and is about 145 pcf (23 KN/mKN/m2)for normal concrete.In calculating the dead load of structural concrete,usually a 5pcf (1 )increment is included with the weight of the concrete to account for the presence of the 2 reinforcement.Live loads are loads such as occupancy,snow,wind,or traffic loads,or seismic forces.They may be either fully or partially in place,or not present at all.They may also change in location.Althought it is the responsibility of the engineer to calculate dead loads,live loads are usually specified by local,regional,or national codes and specifications.Typical sources are the publications of the American National Standards Institute,the American Association of State Highway and Transportation Officials and,for wind loads,the recommendations of the ASCE Task Committee on Wind Forces.Specified live the loads usually include some allowance for overload,and may include measures such as posting of maximum loads will not be exceeded.It is oftern important to distinguish between the specified load,and what is termed the characteristic load,that is,the load that actually is in effect under normal conditions of service,which may be significantly less.In estimating the long-term deflection of a structure,for example,it is the characteristic load that is important,not the specified load.The sum of the calculated dead load and the specified live load is called the service load,because this is the maximum load which may reasonably be expected to act during the service resisting is a multiple of the service load.StrengthThe strength of a structure depends on the strength of the materials from which it is made.Minimum material strengths are specified in certain standardized ways.The properties of concrete and its components,the methods of mixing,placing,and curing to obtain the required quality,and the methods for testing,are specified by the American Concrete Insititue(ACI).Included by refrence in the same documentare standards of the American Society for Testing Materials(ASTM)pertaining to reinforcing and prestressing steels and concrete.Strength also depends on the care with which the structure is built.Member sizes may differ from specified dimensions,reinforcement may be out of position,or poor placement of concrete may result in voids.An important part of the job of the ergineer is to provide proper supervision of construction.Slighting of this responsibility has had disastrous consequences in more than one instance.Structural SafetySafety requires that the strength of a structure be adequate for all loads that may conceivably act on it.If strength could be predicted accurately and if loads were known with equal certainty,then safely could be assured by providing strength just barely in excess of the requirements of the loads.But there are many sources of uncertainty in the estimation of loads as well as in analysis,design,and construction.These uncertainties require a safety margin.In recent years engineers have come to realize that the matter of structural safety isprobabilistic in nature,and the safety provisions of many current specifications reflect this view.Separate consideration is given to loads and strength.Load factors,larger than unity,are applied to the calculated dead loads and estimated or specified service live loads,to obtain factorde loads that the member must just be capable of sustaining at incipient failure.Load factors pertaining to different types of loads vary,depending on the degree of uncertainty associated with loads of various types,and with the likelihood of simultaneous occurrence of different loads.Early in the development of prestressed concrete,the goal of prestressing was the complete elimination of concrete ternsile stress at service loads.The concept was that of an entirely new,homogeneous material that woukd remain uncracked and respond elastically up to the maximum anticipated loading.This kind of design,where the limiting tensile stressing,while an alternative approach,in which a certain amount of tensile amount of tensile stress is permitted in the concrete at full service load,is called partial prestressing.There are cases in which it is necessary to avoid all risk of cracking and in which full prestressing is required.Such cases include tanks or reservious where leaks must be avoided,submerged structures or those subject to a highly corrosive envionment where maximum protection of reinforcement must be insured,and structures subject to high frequency repetition of load where faatigue of the reinforcement may be a consideration.However,there are many cses where substantially improved performance,reduced cost,or both may be obtained through the use of a lesser amount of prestress.Full predtressed beams may exhibit an undesirable amount of upward camber because of the eccentric prestressing force,a displacement that is only partially counteracted by the gravity loads producing downward deflection.This tendency is aggrabated by creep in the concrete,which magnigies the upward displacement due to the prestress force,but has little influence on the should heavily prestressed members be overloaded and fail,they may do so in a brittle way,rather than gradually as do beams with a smaller amount of prestress.This is important from the point of view of safety,because suddenfailure without warning is dangeroud,and gives no opportunity for corrective measures to be taken.Furthermore,experience indicates that in many cases improved economy results from the use of a combination of unstressed bar steel and high strength prestressed steel tendons.While tensile stress and possible cracking may be allowed at full service load,it is also recognized that such full service load may be infrequently applied.The typical,or characteristic,load acting is likely to be the dead load plus a small fraction of the specified live load.Thus a partially predtressed beam may not be subject to tensile stress under the usual conditions of loading.Cracks may from occasionally,when the maximum load is applied,but these will close completely when that load is removed.They may be no more objectionable in prestressed structures than in ordinary reinforced.They may be no more objectionable in prestressed structures than in ordinary reinforced concrete,in which flexural cracks alwaysform.They may be considered a small price for the improvements in performance and economy that are obtained.It has been observed that reinforced concrete is but a special case of prestressed concrete in which the prestressing force is zero.The behavior of reinforced and prestressed concrete beams,as the failure load is approached,is essentially the same.The Joint European Committee on Concrete establishes threee classes of prestressed beams.Class 1:Fully prestressed,in which no tensile stress is allowed in the concrete at service load.Class 2:Partially prestressed, in which occasional temporary cracking is permitted under infrequent high loads.Class 3:Partially prestressed,in which there may be permanent cracks provided that their width is suitably limited.The choise of a suitable amount of prestress is governed by a variety of factors.These include thenature of the loading (for exmaple,highway or railroad bridged,storage,ect.),the ratio of live to dead load,the frequency of occurrence of loading may be reversed,such as in transmission poles,a high uniform prestress would result ultimate strength and in brittle failure.In such a case,partial prestressing provides the only satifactory solution.The advantages of partial prestressing are important.A smaller prestress force will be required,permitting reduction in the number of tendons and anchorages.The necessary flexural strength may be provided in such cases either by a combination of prestressed tendons and non-prestressed reinforcing bars,or by an adequate number of high-tensile tendons prestredded to level lower than the prestressing force is less,the size of the bottom flange,which is requied mainly to resist the compression when a beam is in the unloaded stage,can be reduced or eliminated altogether.This leads in turn to significant simplification and cost reduction in the construction of forms,as well as resulting in structures that are mor pleasing esthetically.Furthermore,by relaxing the requirement for low service load tension in the concrete,a significant improvement can be made in the deflection characteristics of a beam.Troublesome upward camber of the member in the unloaded stage fan be avoeded,and the prestress force selected primarily to produce the desired deflection for a particular loading condition.The behavior of partially prestressed beamsm,should they be overloaded to failure,is apt to be superior to that of fully prestressed beams,because the improved ductility provides ample warning of distress.英译汉:荷载作用在结构上的荷载通常分为恒载或活载。

土木工程专业英语结课论文

土木工程专业英语结课论文

2012级土木工程(本)专业《土木工程英语》课程论文论文题目:高层建筑防火的研究Research of high-rise building fire prevention专业班级:学生姓名:学号:论文成绩:评阅教师:2015年11 月14 日(一)基于性能化防火设计方法的商业综合体典型空间防火优化设计研究正文:改革开放以来,我国市场经济蓬勃发展,各种类型的商业建筑如雨后春笋般涌现。

然而人们在享受高效便捷的购物消费和休闲娱乐的同时,商业综合体及其建筑群的巨大规模、多样功能、众多人数、复杂流线、与城市多层面多点衔接等特点,极大程度地增大了灾害风险,特别是城市和建筑中最易发生的灾种——火灾的风险。

传统的建筑防火设计以“条文式”的防火规范为依据,无法满足部分现代商业综合体迅速发展的设计需要,当因结构、功能、造型等方面的特殊要求,出现现行国家消防技术规范中未明确规定的、现行国家消防技术规范规定的条件不适用的、依照国家消防技术规范进行设计确有困难的情况时,将采取针对性更强、更加先进、经济、合理、有效的性能化防火措施进行建筑和规划设计。

与此同时,性能化防火设计方法以其在火灾场景和人员疏散模拟等方面的突出优势,也将被更多地运用于优化“条文式”防火设计规范框架内的规划与建筑方案设计。

可见研究大型商业综合体的性能化防火设计措施,并利用性能化防火设计的方法调整优化规划与建筑设计以避免和减轻火灾危害是亟待解决的重要课题。

本论文共分为十章,分别介绍了课题的研究背景与意义,国内外商业综合体性能化防火的研究现状,要素构成及火灾危险性,建筑的火灾机理与性能化防火设计参数,五大类商业综合体典型空间的防火优化措施,最后提出结论与展望。

本文的核心研究内容是结合商业综合体空间要素构成特征的火灾特点以及建筑防火设计中的三个重要指标(防火分区、疏散距离、疏散宽度),提炼五大类商业综合体的典型空间,即密集空间、竖向贯通空间、超大水平开敞空间、狭长通道空间和地下空间,以建筑学和城市规划学的视角,一方面运用计算机技术,对“超规范”的设计方案进行性能化防火设计安全评价,另一方面对条文式规范框架内的设计方法进行优化。

论文篇-土木工程英文-论文

论文篇-土木工程英文-论文

Buried tunnel project on the environmentAbstract: a deeply buried tunnel far-reaching impact on the environment through the waterways with the sinking pipe related. Under the tunnel on the mainland in the region and the impact of surface water in the tunnel design and construction method of choice to play the most important role. In considering the impact of the recent construction of a problem is the need to trench excavation for the tunnel may appear to be contaminated soil. And transporting the excavated soil up to the specialized equipment in order to receive their storage place is a series of important new technologies and quality control measures for environmental problems. The most common is in any construction project will encounter environmental problems, namely, noise, dust and traffic congestion. In this paper, these issues and the current technology to address these issues and measures are discussed.Key words: tunnel environmentCharacteristics of a Buried deeply buried tunnel tunnel has two fundamental characteristics: (1) It is part of an underground structure of the site, to ensure that heavy traffic conditions, construction, and does not mean that this area is full use of The. Therefore, the construction space is very valuable.Will eventually be installed in the location of the river or canal bottom section of tunnel is very close in other areas to build manufacturing plants, ways, and this condition is unlikely in the field and reached the site. The advantages of planning and construction of pipe manufacture and the site will be ready to separate from the logistical advantages are obvious, there are extremely easy to implement effective quality control advantages.Tunnel work site on the environmental impact is also considerablyless than the construction of the tunnel fully all the circumstances at the scene; such as space requirements and construction of transport, these two issues is greatly easing.Of course, a prerequisite for these benefits is a ready-made for pipe suitable site. It must meet the conditions for a series of environmental impact. In the Netherlands such as densely populated countries, to find a suitable site is not easy, but it is clear that once selected an available position, can be used repeatedly for quite a draw a crowd. Therefore, the overall plan for the tunnel construction is a common topic for discussion.Both ends of the structure of a new underground tunnel link to the original structure to the existing underground, often in fact across the waters to replace an existing facility, such as ferry or bridge. It can also be a complement existing facilities in tunnels or bridges. Whether the decision to build a new tunnel the reason, its location will be in large part by the constraints of existing underground structure layout, and its construction design must also meet the existing transport only by the requirements of minimal interference. This means that the location in the tunnel area designers rarely have a choice, and thus have the position according to the established conditions and requirements to modify the tunnel design.This situation mainly affects the approach roads connecting part of the tunnel itself. However, because the approach road through the water by the formation of sub-components, it may require new measures to control the approaches to the scope of the construction pit drainage impact.Buried Tunnel approach roads are almost always located in the deposition zone, where the tunnel approach road down to the groundwater level below. At its completion, they are impervious structure, the surrounding water can not penetrate, there's just the nature of the environmental impact of a simple structure.However, during construction, environmental issues will play an important role. To build from the structures, construction of foundation must be excavated until the water table following a number of meters deep,the traditional construction method requires the construction period in the continuous draining of the water. Unless further measures, or drainage will definitely lower the water level in the surrounding area, and will lead to a series of undesirable consequences. Subsidence will occur, based on the surrounding buildings and structures will be affected, and even deep pile foundation soil settlement will also be passed by the friction down to the pile on the extra load. Subsidence and elevation of the dam sinking, and agricultural drainage water will be affected.May also result in a completely different nature of environmental problems: the construction area may be contaminated soil. In this case, the construction of the excavation pit special attention to requirements and, if possible, should be used, such as soil mixed with water and water transport by pipeline, special methods. There must also be able to accommodate an approved place of contaminated soil.Number of measures must be taken to prevent the pumping of contaminated water caused by the rapid distribution of the soil to a large area on the ground.Technically speaking, is always possible to eliminate the impact of these kinds. However, it is extremely complex and do take a lot of money and time, therefore, tend to look at present the greatest extent possible the construction of approach roads and tunnels in the water imported methods. Ideally, the empty pit in the construction of a drainage of water should be no impact on the approach roads and the surrounding groundwater single operation.The obvious conclusion is that as far as possible the construction pit designed as part of the final product.Approach a wall can be designed to image the wall of the dam impervious core in the form of a slurry wall, curtain or plastic sheet of steel sheet pile walls common. On the final form (steel sheet pile wall) (off panel through the use of heavy anchor piles and soil) to increase its retaining function, you can save valuable space and can be easily achieved in the water and impermeable floor connection.Water under the concrete floor can be built. This approach hasbeen developed to control the elevation and surface roughness, which completely drained to the approach road after finishing requires less work.Another method is the use of impermeable plastic sheet, add water to the town of emphasis placed on the bottom and cover the pit slope. In the Netherlands, this approach not only for the tunnel approaches, and the groove for the public network segment.Use large plastic sheet, to the soil to the water for the town re-placed by a major highway intersection in the play a long-term good results, it shows that this technology has been widely used. Soon, the Netherlands, the tunnel approach roads may be to show a lush green slope, thereby replacing the gray concrete vertical wall.Approach can also be prefabricated elsewhere and in the form of installation of floating structures. This method only with trench excavation and dredging vessels do not have to drain. But not yet able to adequately address basic problems of buoyancy and appropriate design. Buried tunnel project on the environmentPipe manufacturing approaches to the excavation of underground water and the discussion of the relationship between the way the majority can be used to produce the same pipe excavation of the temporary venues. Expensive solution to bring an unreasonable burden to the project. Moreover, the manufacture of pipe near the site have repeatedly flooded the open waters and open to the precast tunnel segments into the transportation to the dock at the other pipe section in order to make room. Rarely a large enough place for all of the pipe manufacturer.In short, the choice of the location of manufacturing pipe dock not chosen as the location of the tunnel approach roads to be strictly determined by functional requirements, so choose the location of manufacturing pipe dock with the advantages of flexibility. Therefore, the manufacture of docks will be allowed to use the traditional water method, if the reasons listed above that do not allow the use of traditional water law, and the dock had to separate from the surrounding water, this places impermeable plastic plate because of its low cost to have obvious advantages.Another does not affect the drainage around the water table is "pumping recharge Law" This law is the foundation of the water into the pump discharge and pump water through the filter of these tube wells to the water source recharge area. As long as the penetration rate is not too large and can be maintained roughly a constant, the row, when the closed-loop irrigation can be maintained. The new measures, now being expanded in the Netherlands approaches to the construction of a pit, but also because the foundation of the dock as the manufacture of pipe it to be expanded.Construction of foundation trench trough structure deeply buried tunnel excavation method is dredging. In this paper, we only stress the importance of dredging requirements of foundation trench excavation method can achieve high accuracy, and this requires that the work will determine the most suitable type of device. Given the strict positioning tolerances, preferably dredging boat anchor or pile in positioning the dredging equipment. However, because they can not move freely, it could become an obstacle to shipping vessels.If there is water in the dredging area, or the wave of the impact of dredging will become the base slot to carry water along the bottom or sediment accumulation over the place. If the foundation trench excavation in place pipe for long periods, it will soon form a deposition. In these circumstances, the base section of tank excavation and tunnel installation of the interval between the two processes must be as short as possible, and thus the arrangement of the two procedure are to be particularly accurate, you can use a special device to clean the base before the installation of pipe slot. In the Netherlands, this operation has been developed to be used in the East (Eastern Scheldt) anti-dam pier storm waves reach a very high precision installation.Dredging stir up the river sediments, resulting in a certain time a certain area of the water turbidity. Eventually become a suspended fine particles of these substances will spread out and gradually settle down again. Although this process had limited impact on the environment, and harmless, but in a certain range or the increasingly strong criticism.If you want to have dredged soil is contaminated, it is even more complicated, because in such conditions, the dredging operation will cause the spread of contamination. Dredging technology has now developed to the drain by using a special mud head to eliminate this effect. Under the floating boat by hanging curtains from the dredging area will be completely separated from the surrounding method may also reduce the spread of pollution.Further development in this regard we have taken note of the current, most waterways in the Netherlands contain contaminated bottom sediments have been very clear, so dredging the mud is bound to take some special environmental requirements.Currently, these requirements have not been unified to form, but made different for each specific project requirements. Hope that this delay in the development of key technologies of the chaos can be quickly resolved.According to the type and extent of contamination, contaminated soil can be divided into 1 to 4 classes. For dredging mud (including dredging process water in the process) and disposal are subject to strict restrictions by category; particular, 3 and 4 the soil must be isolated, and in possible to be purified.In the Rotterdam area, has built a store of these solid waste and other hazardous substances the center of the dump site. In addition, Type 4 is placed in temporary dredging spoil heap smaller point, let it be purified and then transferred to another isolated place repository. Place in the absence of such facilities to be established by dredging this dump sites. This measure is a clear need to do a lot of work.Transportation and installation of pipe work and dredging the shipping obstacles to transport and install pipe sections are brought about environmental problems. To open the pipe system and installation of marinas and docks to deepen the shallow waters between the points need to channel dredging operations. Some of the previous discussion about dredging also apply to this situation.The installation procedures in a particular area may involve theend of the tunnel-based clean-up slot. To make clean-up and installation of the two processes reduce to a minimum interval of time, placed in the pipe to its final position before the bottom of the sand filling has been successfully used to shoot clean water law section of the base tunnel. With a powerful water jet to remove the last layer of the sediment washed into the suspension, followed by water flow away.Left in the pipe manufacturing dock, anchored at the temporary terminal and leave the temporary pier, floating point and transported to the installation during installation are likely to hinder shipping. Only the last one caused by the shipping process will complete in the short term temporary interruption or partial interruption.In this respect, a deeply buried tunnel across a river and there are differences across a canal. In the latter case, the absence of flow effects to make the sinking and installation of pipe can be better controlled. The advantage of this control to allow the use of more deeply buried sections of the tunnel tube pipe unit, but it must be large enough to create dock.Therefore, in the Netherlands, in the past most deeply buried pipe unit length of the tunnel are varied between 100 ~ 150m, crossing the North Sea Canal between Amsterdam and the Trondheim area tunnel (Hemtunnel) project has also used the unit for up to 268m of pipe . Use a longer pipe unit reduces the number of installation, which will slow down the barriers to shipping.Buried pipe for the tunnel project, it seems to impede the shipping for the environment as a problem, but not a major problem.This process includes filling with sand filling pipe at the base, back to the filling tank, and, if necessary in the pipe at the top of the construction of a scour protection layer.Backfill material must be uncontaminated. Ship in the tunnel construction work will interfere with the above shipping. However, by using a pipe installed in the tunnel were part of the operation of equipment, we can reduce such problems, for example, through the tunnel at the bottom of the holes by pumping sand and water mixture to backfilling.This system has been successfully applied in the Netherlands.Tunnel operation and maintenance operations involving major environmental issue is ventilation.Cleaning and maintenance of the tunnel wall to obstruct the road vehicle operation, they must be in the appropriate period of time quickly. Smooth wall and good coating helps to clean the operating table, thus reducing the time limit traffic through the tunnel.Road construction must be done to minimize future maintenance.。

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2012级土木工程(本)专业《土木工程英语》课程论文论文题目:高层建筑防火的研究Research of high-rise building fire prevention专业班级:学生姓名:学号:论文成绩:评阅教师:2015年11 月14 日(一)基于性能化防火设计方法的商业综合体典型空间防火优化设计研究正文:改革开放以来,我国市场经济蓬勃发展,各种类型的商业建筑如雨后春笋般涌现。

然而人们在享受高效便捷的购物消费和休闲娱乐的同时,商业综合体及其建筑群的巨大规模、多样功能、众多人数、复杂流线、与城市多层面多点衔接等特点,极大程度地增大了灾害风险,特别是城市和建筑中最易发生的灾种——火灾的风险。

传统的建筑防火设计以“条文式”的防火规范为依据,无法满足部分现代商业综合体迅速发展的设计需要,当因结构、功能、造型等方面的特殊要求,出现现行国家消防技术规范中未明确规定的、现行国家消防技术规范规定的条件不适用的、依照国家消防技术规范进行设计确有困难的情况时,将采取针对性更强、更加先进、经济、合理、有效的性能化防火措施进行建筑和规划设计。

与此同时,性能化防火设计方法以其在火灾场景和人员疏散模拟等方面的突出优势,也将被更多地运用于优化“条文式”防火设计规范框架内的规划与建筑方案设计。

可见研究大型商业综合体的性能化防火设计措施,并利用性能化防火设计的方法调整优化规划与建筑设计以避免和减轻火灾危害是亟待解决的重要课题。

本论文共分为十章,分别介绍了课题的研究背景与意义,国内外商业综合体性能化防火的研究现状,要素构成及火灾危险性,建筑的火灾机理与性能化防火设计参数,五大类商业综合体典型空间的防火优化措施,最后提出结论与展望。

本文的核心研究内容是结合商业综合体空间要素构成特征的火灾特点以及建筑防火设计中的三个重要指标(防火分区、疏散距离、疏散宽度),提炼五大类商业综合体的典型空间,即密集空间、竖向贯通空间、超大水平开敞空间、狭长通道空间和地下空间,以建筑学和城市规划学的视角,一方面运用计算机技术,对“超规范”的设计方案进行性能化防火设计安全评价,另一方面对条文式规范框架内的设计方法进行优化。

性能化防火策略作为消防设计乃至贯穿整个建筑、规划设计全过程的设计思路,已初步为我们展现出应用领域的美好前景,本文旨在进一步完善和发展以数字技术为基础的性能化防火设计方法,为建筑和城市减灾防灾目标的实现提供更有力的保障。

翻译:Based on the performance-based fire protection design method of typicalcommercial complex space fire prevention optimization design researchSince the reform and opening, our country market economy booming, the various types of commercial buildings have sprung up. Yet people enjoying the high efficient and convenient shopping consumption and entertainment at the same time, commercial complexes and the large scale complex complex, diverse functions, the number of many, streamline, and city level more cohesive characteristics of drastically increases the risk of disasters, the especially urban and building most likely to occur in the mined-out area, the risk of fire. Traditional building fire protection design based on "provision" code for fire protection, cannot meet the design needs to be part of the rapid development of modern commercial complex, when because of the special requirements of structure, function, shape, etc, in the current national fire did not explicitly stipulated in the technical specification and the conditions stipulated in the current national fire protection specification is not applicable, in accordance with the national fire protection technology specification of design difficulties, will take a more targeted, more advanced, economic, reasonable and effective performance-based fire protection measures for construction and planning and design. At the same time, the performance-based fire protection design method for its in fire scenario and evacuation simulation and so on the prominent advantage of, will also be more applied to optimize the "provision" fire prevention design specification within the framework of the planning and architectural design. Visible study measures the performance-based fire-protection design of large commercial complex, and by using the method of performance-based fire protection design of adjusting and optimizing the planning and architectural design in order to avoid and reduce the fire hazard is one of the important subjects to be solved. This thesis is divided into ten chapters, respectively introduced the research background and significance, the research status of commercial complex, the performance-based fire protection at home and abroad, the elements and fire danger, building the fire mechanism and parameters of the performance-based fire-protection design, five commercial complex typical fire prevention measures of the space, finally put forward the conclusion and prospect. Core content in the research of this paper is combined with the feature of commercial space of complex elements of fire characteristics and three important indicators in thedesign of building fire protection (fire partition, travel distance, evacuation width), refining the five kinds of typical space of commercial complex, namely the level of intensive space and vertical space, large open space, narrow channel space and underground space, in the perspective of architecture and urban planning, on the one hand, using computer technology, the design scheme of "super specification" for safety evaluation of the performance-based fire-protection design, on the other hand the provisions type specification within the framework of the design method of optimization. Performance-based fire protection strategy for fire protection design and even throughout the building, the design idea of the planning and design process, preliminary already for our show a prospect in the field of application, this article aims to further perfect and development on the basis of the digital technology method of performance-based fire protection design of buildings and urban disaster reduction to provide a more powerful safeguard to achieve the goal of disaster prevention.(二)Damage identification of reinforced concrete structures after fire andreinforcementFire except caused a great loss to human life and property, injury and damage on the building structure itself is also very serious. Especially in recent years, because of the high-rise buildings, large scale and the use of compound, the happening of building fire was gradually rising trend. In all kinds of building structure, reinforced concrete structure holds the largest share. So far, domestic and foreign research work of the fire resistance of concrete structural components is limited, the comprehensive identification and evaluation of fire damage structure also at groping stage, our country's at present there is no clear rules or regulations to follow, also can not adapt to the needs of the development of engineering construction. Therefore, the detection and identification of structure damage after fire and repair design scheme optimization research both at home and abroad caused the enough attention, in-depth study of its theory and practice is of great social significance and economic benefits. This article collects and analyses the existing fire literatures about reinforcedconcrete structure at home and abroad, combined with engineering practice experience and specific engineering example, the material mechanics performance of reinforced concrete structures after fire and the change of component bearing capacity, damage detection and identification method of the structure and structure reinforcement calculation and design system is analyzed and summarized. On this basis, the key of reinforced concrete structures after fire detection method, the damaged degree of comprehensive appraisal standard and reinforcement design scheme are studied and discussed, and puts forward some effective methods and Suggestions, for the future of building fire actual engineering research and provide some references for repair reinforcement design. This paper from the analysis of fire resistance of reinforced concrete materials and components, summed up the steel and concrete materials in high temperature mechanical properties under the action of fire, further expounds the fire resistance and bearing capacity of reinforced concrete structures. Building fire temperature determination is a complex work, this paper analyzes the methods to determine the fire temperature. Then systematically summarizes the detection methods of materials and the damaged structure after fire, and analyzes their respective advantages and disadvantages and applicable scope. And summed up the concrete structure and components of fire damage level and evaluation criteria, for the actual fire engineering detection and identification of the damaged structure and repair reinforcement application. This article also probes into the concrete member after the fire remaining bearing capacity calculation, the common reinforcement methods and reinforcement of the concrete structure calculation theory and reinforcement design. Finally, this paper apply the above theory research specific to fire engineering instance. In engineering examples, this paper deeply studied the following content: (1) in view of the concrete structure after fire damage a variety of detection method is applied to conduct site test; (2) comprehensive fire scene investigation and test result shows the damage identification and bearing capacity of the project, all kinds of the damaged structure reliability conclusions; (3) take the typical damaged concrete members, such as: frame beams and columns as the research object, analyzed the fire damage phenomenon and fire resistance, gives some verification conclusion; (4) according to the appraisal result, advances some Suggestions on the project repair reinforcement concrete reinforcement method, and a reinforcement scheme design was carried out.翻译:火灾后钢筋混凝土结构的受损鉴定与修复加固火灾除了造成人类生命和财产的巨大损失之外,对建筑结构本身的损伤和破坏也是非常严重的。

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