钢结构毕业设计论文(中英)

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毕业设计的论文中英翻译

毕业设计的论文中英翻译

Anti-Aircraft Fire Control and the Development of IntegratedSystems at SperryT he dawn of the electrical age brought new types of control systems. Able to transmit data between distributed components and effect action at a distance, these systems employed feedback devices as well as human beings to close control loops at every level. By the time theories of feedback and stability began to become practical for engineers in the 1930s a tradition of remote and automatic control engineering had developed that built distributed control systems with centralized information processors. These two strands of technology, control theory and control systems, came together to produce the large-scale integrated systems typical of World War II and after.Elmer Ambrose Sperry (I860-1930) and the company he founded, the Sperry Gyroscope Company, led the engineering of control systems between 1910 and 1940. Sperry and his engineers built distributed data transmission systems that laid the foundations of today‟s command and control systems. Sperry‟s fire control systems included more than governors or stabilizers; they consisted of distributed sensors, data transmitters, central processors, and outputs that drove machinery. This article tells the story of Sperry‟s involvement in anti-aircraft fire control between the world wars and shows how an industrial firm conceived of control systems before the common use of control theory. In the 1930s the task of fire control became progressively more automated, as Sperry engineers gradually replaced human operators with automatic devices. Feedback, human interface, and system integration posed challenging problems for fire control engineers during this period. By the end of the decade these problems would become critical as the country struggled to build up its technology to meet the demands of an impending war.Anti-Aircraft Artillery Fire ControlBefore World War I, developments in ship design, guns, and armor drove the need for improved fire control on Navy ships. By 1920, similar forces were at work in the air: wartime experiences and postwar developments in aerial bombing created the need for sophisticated fire control for anti-aircraft artillery. Shooting an airplane out of the sky is essentially a problem of “leading” the target. As aircraft developed rapidly in the twenties, their increased speed and altitude rapidly pushed the task of computing the lead out of the range of human reaction and calculation. Fire control equipment for anti-aircraft guns was a means of technologically aiding human operators to accomplish a task beyond their natural capabilities.During the first world war, anti-aircraft fire control had undergone some preliminary development. Elmer Sperry, as chairman of the Aviation Committee of the Naval Consulting Board, developed two instruments for this problem: a goniometer,a range-finder, and a pretelemeter, a fire director or calculator. Neither, however, was widely used in the field.When the war ended in I918 the Army undertook virtually no new development in anti-aircraft fire control for five to seven years. In the mid-1920s however, the Army began to develop individual components for anti-aircraft equipment including stereoscopic height-finders, searchlights, and sound location equipment. The Sperry Company was involved in the latter two efforts. About this time Maj. Thomas Wilson, at the Frankford Arsenal in Philadelphia, began developing a central computer for firecontrol data, loosely based on the system of “director firing” that had developed in naval gunn ery. Wilson‟s device resembled earlier fire control calculators, accepting data as input from sensing components, performing calculations to predict the future location of the target, and producing direction information to the guns.Integration and Data TransmissionStill, the components of an anti-aircraft battery remained independent, tied together only by telephone. As Preston R. Bassett, chief engineer and later president of the Sperry Company, recalled, “no sooner, however, did the components get to the point of functioning satisfactorily within themselves, than the problem of properly transmitting the information from one to the other came to be of prime importance.”Tactical and terrain considerations often required that different fire control elements be separated by up to several hundred feet. Observers telephoned their data to an officer, who manually entered it into the central computer, read off the results, and telephoned them to the gun installations. This communication system introduced both a time delay and the opportunity for error. The components needed tighter integration, and such a system required automatic data communications.In the 1920s the Sperry Gyroscope Company led the field in data communications. Its experience came from Elmer Spe rry‟s most successful invention, a true-north seeking gyro for ships. A significant feature of the Sperry Gyrocompass was its ability to transmit heading data from a single central gyro to repeaters located at a number of locations around the ship. The repeaters, essentially follow-up servos, connected to another follow-up, which tracked the motion of the gyro without interference. These data transmitters had attracted the interest of the Navy, which needed a stable heading reference and a system of data communication for its own fire control problems. In 1916, Sperry built a fire control system for the Navy which, although it placed minimal emphasis on automatic computing, was a sophisticated distributed data system. By 1920 Sperry had installed these systems on a number of US. battleships.Because of the Sperry Company‟s experience with fire control in the Navy, as well as Elmer Sperry‟s earlier work with the goniometer and the pretelemeter, the Army approached the company for help with data transmission for anti-aircraft fire control. To Elmer Sperry, it looked like an easy problem: the calculations resembled those in a naval application, but the physical platform, unlike a ship at sea, anchored to the ground. Sperry engineers visited Wilson at the Frankford Arsenal in 1925, and Elmer Sperry followed up with a letter expressing his interest in working on the problem. He stressed his company‟s experience with naval problems, as well as its recent developments in bombsights, “work from the other end of the pro position.” Bombsights had to incorporate numerous parameters of wind, groundspeed, airspeed, and ballistics, so an anti-aircraft gun director was in some ways a reciprocal bombsight . In fact, part of the reason anti-aircraft fire control equipment worked at all was that it assumed attacking bombers had to fly straight and level to line up their bombsights. Elmer Sperry‟s interests were warmly received, and in I925 and 1926 the Sperry Company built two data transmission systems for the Army‟s gun directors.The original director built at Frankford was designated T-1, or the “Wilson Director.” The Army had purchased a Vickers director manufactured in England, but encouraged Wilson to design one thatcould be manufactured in this country Sperry‟s two data tran smission projects were to add automatic communications between the elements of both the Wilson and the Vickers systems (Vickers would eventually incorporate the Sperry system into its product). Wilson died in 1927, and the Sperry Company took over the entire director development from the Frankford Arsenal with a contract to build and deliver a director incorporating the best features of both the Wilson and Vickers systems. From 1927 to 193.5, Sperry undertook a small but intensive development program in anti-aircraft systems. The company financed its engineering internally, selling directors in small quantities to the Army, mostly for evaluation, for only the actual cost of production [S]. Of the nearly 10 models Sperry developed during this period, it never sold more than 12 of any model; the average order was five. The Sperry Company offset some development costs by sales to foreign govemments, especially Russia, with the Army‟s approval 191.The T-6 DirectorSperry‟s modified version of Wilson‟s director was designated T-4 in development. This model incorporated corrections for air density, super-elevation, and wind. Assembled and tested at Frankford in the fall of 1928, it had problems with backlash and reliability in its predicting mechanisms. Still, the Army found the T-4 promising and after testing returned it to Sperry for modification. The company changed the design for simpler manufacture, eliminated two operators, and improved reliability. In 1930 Sperry returned with the T-6, which tested successfully. By the end of 1931, the Army had ordered 12 of the units. The T-6 was standardized by the Army as the M-2 director.Since the T-6 was the first anti-aircraft director to be put into production, as well as the first one the Army formally procured, it is instructive to examine its operation in detail. A technical memorandum dated 1930 explained the theory behind the T-6 calculations and how the equations were solved by the system. Although this publication lists no author, it probably was written by Earl W. Chafee, Sperry‟s director of fire control engineering. The director was a complex mechanical analog computer that connected four three-inch anti-aircraft guns and an altitude finder into an integratedsystem (see Fig. 1). Just as with Sperry‟s naval fire control system, the primary means of connection were “data transmitters,” similar to those that connected gyrocompasses to repeaters aboard ship.The director takes three primary inputs. Target altitude comes from a stereoscopic range finder. This device has two telescopes separated by a baseline of 12 feet; a single operator adjusts the angle between them to bring the two images into coincidence. Slant range, or the raw target distance, is then corrected to derive its altitude component. Two additional operators, each with a separate telescope, track the target, one for azimuth and one for elevation. Each sighting device has a data transmitter that measures angle or range and sends it to the computer. The computer receives these data and incorporates manual adjustments for wind velocity, wind direction, muzzle velocity, air density, and other factors. The computer calculates three variables: azimuth, elevation, and a setting for the fuze. The latter, manually set before loading, determines the time after firing at which the shell will explode. Shells are not intended to hit the target plane directly but rather to explode near it, scattering fragments to destroy it.The director performs two major calculations. First, pvediction models the motion of the target and extrapolates its position to some time in the future. Prediction corresponds to “leading” the target. Second, the ballistic calculation figures how to make the shell arrive at the desired point in space at the future time and explode, solving for the azimuth and elevation of the gun and the setting on the fuze. This calculation corresponds to the traditional artillery man‟s task of looking up data in a precalculated “firing table” and setting gun parameters accordingly. Ballistic calculation is simpler than prediction, so we will examine it first.The T-6 director solves the ballistic problem by directly mechanizing the traditional method, employing a “mechanical firing table.” Traditional firing tables printed on paper show solutions for a given angular height of the target, for a given horizontal range, and a number of other variables. The T-6 replaces the firing table with a Sperry ballistic cam.” A three-dimensionally machined cone shaped device, the ballistic cam or “pin follower” solves a pre-determined function. Two independent variables are input by the angular rotation of the cam and the longitudinal position of a pin that rests on top of the cam. As the pin moves up and down the length of the cam, and as the cam rotates, the height of the pin traces a function of two variables: the solution to the ballistics problem (or part of it). The T-6 director incorporates eight ballistic cams, each solving for a different component of the computation including superelevation, time of flight, wind correction, muzzle velocity. air density correction. Ballistic cams represented, in essence, the stored data of the mechanical computer. Later directors could be adapted to different guns simply by replacing the ballistic cams with a new set, machined according to different firing tables. The ballistic cams comprised a central component of Sperry‟s mechanical computing technology. The difficulty of their manufacture would prove a major limitation on the usefulness of Sperry directors.The T-6 director performed its other computational function, prediction, in an innovative way as well. Though the target came into the system in polar coordinates (azimuth, elevation, and range), targets usually flew a constant trajectory (it was assumed) in rectangular coordinates-i.e. straight andlevel. Thus, it was simpler to extrapolate to the future in rectangular coordinates than in the polar system. So the Sperry director projected the movement of the target onto a horizontal plane, derived the velocity from changes in position, added a fixed time multiplied by the velocity to determine a future position, and then converted the solution back into polar coordinates. This method became known as the “plan prediction method”because of the representation of the data on a flat “plan” as viewed from above; it was commonly used through World War II. In the plan prediction method, “the actual movement of the target is mechanically reproduced on a small scale within the Computer and the desired angles or speeds can be measured directly from the movements of these elements.”Together, the ballistic and prediction calculations form a feedback loop. Operators enter an estimated “time of flight” for the shell when they first begin tracking. The predictor uses this estimate to perform its initial calculation, which feeds into the ballistic stage. The output of the ballistics calculation then feeds back an updated time-of-flight estimate, which the predictor uses to refine the initial estimate. Thus “a cumulative cycle of correction brings the predicted future position of the target up to the point indicated by the actual future time of flight.”A square box about four feet on each side (see Fig. 2) the T-6 director was mounted on a pedestal on which it could rotate. Three crew would sit on seats and one or two would stand on a step mounted to the machine. The remainder of the crew stood on a fixed platform; they would have had to shuffle around as the unit rotated. This was probably not a problem, as the rotation angles were small. The direc tor‟s pedestal mounted on a trailer, on which data transmission cables and the range finder could be packed for transportation.We have seen that the T-6 computer took only three inputs, elevation, azimuth, and altitude (range), and yet it required nine operators. These nine did not include the operation of the range finder, which was considered a separate instrument, but only those operating the director itself. What did these nine men do?Human ServomechanismsTo the designers of the director, the operato rs functioned as “manual servomechanisms.”One specification for the machine required “minimum dependence on …human element.‟ The Sperry Company explained, “All operations must be made as mechanical and foolproof as possible; training requirements must visualize the conditions existent under rapid mobilization.” The lessons of World War I ring in this statement; even at the height of isolationism, with the country sliding into depression, design engineers understood the difficulty of raising large numbers of trained personnel in a national emergency. The designers not only thought the system should account for minimal training and high personnel turnover, they also considered the ability of operators to perform their duties under the stress of battle. Thus, nearly all the work for the crew was in a “follow-the-pointer”mode: each man concentrated on an instrument with two indicating dials, one the actual and one the desired value for a particular parameter. With a hand crank, he adjusted the parameter to match the two dials.Still, it seems curious that the T-6 director required so many men to perform this follow-the-pointer input. When the external rangefinder transmitted its data to the computer, it appeared on a dial and an operator had to follow the pointer to actually input the data into the computing mechanism. The machine did not explicitly calculate velocities. Rather, two operators (one for X and one for Y) adjusted variable-speed drives until their rate dials matched that of a constant-speed motor. When the prediction computation was complete, an operator had to feed the result into the ballistic calculation mechanism. Finally, when the entire calculation cycle was completed, another operator had to follow the pointer to transmit azimuth to the gun crew, who in turn had to match the train and elevation of the gun to the pointer indications.Human operators were the means of connecting “individual elements” into an integrated system. In one sense the men were impedance amplifiers, and hence quite similar to servomechanisms in other mechanical calculators of the time, especially Vannevar Bush‟s differential analyzer .The term “manual servomechanism”itself is an oxymoron: by the conventional definition, all servomechanisms are automatic. The very use of the term acknowledges the existence of an automatic technology that will eventually replace the manual method. With the T-6, this process was already underway. Though the director required nine operators, it had already eliminated two from the previous generation T-4. Servos replaced the operator who fed back superelevation data and the one who transmitted the fuze setting. Furthermore, in this early machine one man corresponded to one variable, and the machine‟s requirement for operators corresponded directly to the data flow of its computation. Thus the crew that operated the T-6 director was an exact reflection of the algorithm inside it.Why, then, were only two of the variables automated? This partial, almost hesitating automation indicates there was more to the human servo-motors than Sperry wanted to acknowledge. As much as the company touted “their duties are purely mechanical and little skill or judgment is required on the part of the operators,” men were still required to exercise some judgment, even if unconsciously. The data were noisy, and even an unskilled human eye could eliminate complications due to erroneous or corrupted data. The mechanisms themselves were rather delicate and erroneous input data, especially if it indicated conditions that were not physically possible, could lock up or damage the mechanisms. Theoperators performed as integrators in both senses of the term: they integrated different elements into a system.Later Sperry DirectorsWhen Elmer Sperry died in 1930, his engineers were at work on a newer generation director, the T-8. This machine was intended to be lighter and more portable than earlier models, as well as less expensive and “procurable in quantities in case of emergency.” The company still emphasized the need for unskilled men to operate the system in wartime, and their role as system integrators. The operators were “mechanical links in the apparatus, thereby making it possible to avoid mechanical complication which would be involved by the use of electrical or mechanical servo motors.” Still, army field experience with the T-6 had shown that servo-motors were a viable way to reduce the number of operators and improve reliability, so the requirements for the T-8 specified that wherever possible “electrical shall be used to reduce the number of operators to a minimum.” Thus the T-8 continued the process of automating fire control, and reduced the number of operators to four. Two men followed the target with telescopes, and only two were required for follow-the-pointer functions. The other follow-the-pointers had been replaced by follow-up servos fitted with magnetic brakes to eliminate hunting. Several experimental versions of the T-8 were built, and it was standardized by the Army as the M3 in 1934.Throughout the remain der of the …30s Sperry and the army fine-tuned the director system in the M3. Succeeding M3 models automated further, replacing the follow-the-pointers for target velocity with a velocity follow-up which employed a ball-and-disc integrator. The M4 series, standardized in 1939, was similar to the M3 but abandoned the constant altitude assumption and added an altitude predictor for gliding targets. The M7, standardized in 1941, was essentially similar to the M4 but added full power control to the guns for automatic pointing in elevation and azimuth. These later systems had eliminated errors. Automatic setters and loaders did not improve the situation because of reliability problems. At the start of World War II, the M7 was the primary anti-aircraft director available to the army.The M7 was a highly developed and integrated system, optimized for reliability and ease of operation and maintenance. As a mechanical computer, it was an elegant, if intricate, device, weighing 850 pounds and including about 11,000 parts. The design of the M7 capitalized on the strength of the Sperry Company: manufacturing of precision mechanisms, especially ballistic cams. By the time the U.S. entered the second world war, however, these capabilities were a scarce resource, especially for high volumes. Production of the M7 by Sperry and Ford Motor Company as subcontractor was a “real choke” and could not keep up with production of the 90mm guns, well into 1942. The army had also adopted an English system, known as the “Kerrison Director” or M5, which was less accurate than the M7 but easier to manufacture. Sperry redesigned the M5 for high-volume production in 1940, but passed in 1941.Conclusion: Human Beings as System IntegratorsThe Sperry directors we have examined here were transitional, experimental systems. Exactly for that reason, however, they allow us to peer inside the process of automation, to examine the displacement of human operators by servomechanisms while the process was still underway. Skilled asthe Sperry Company was at data transmission, it only gradually became comfortable with the automatic communication of data between subsystems. Sperry could brag about the low skill levels required of the operators of the machine, but in 1930 it was unwilling to remove them completely from the process. Men were the glue that held integrated systems together.As products, the Sperry Company‟s anti-aircraft gun directors were only partially successful. Still, we should judge a technological development program not only by the machines it produces but also by the knowledge it creates, and by how that knowledge contributes to future advances. Sperry‟s anti-aircraft directors of the 1930s were early examples of distributed control systems, technology that would assume critical importance in the following decades with the development of radar and digital computers. When building the more complex systems of later years, engineers at Bell Labs, MIT, and elsewhere would incorporate and build on the Sperry Company‟s experience,grappling with the engineering difficulties of feedback, control, and the augmentation of human capabilities by technological systems.在斯佩里防空炮火控和集成系统的发展电气时代的到来带来了新类型的控制系统。

结构稳定理论之钢结构设计论文英文版

结构稳定理论之钢结构设计论文英文版

Graduate Course Work Steel Structure Stability DesignSchool: China University of MiningName: Liu FeiStudent ID: TSP130604088Grade: 2013Finish Date: 2014.1.1AbstractSteel structure has advantages of light weight, high strength and high degree of industryali zation, which has been widely used in the construction engineering. We often hear this the accident case caused by its instability and failure of structure of casualties and property losses, and the cause of the failure is usually caused by structure design flaws. This paper says the experiences in the design of stability of steel structure through the summary of the stability of steel structure design of the concept, principle, analysis method and combination with engineering practice.Key words:steel structure; stability design; detail structureSteel Structure Stability DesignStructurally stable systems were introduced by Aleksandr Andronov and Lev Pontryagin in 1937 under the name "systèmes grossières", or rough systems. They announced a characterization of rough systems in the plane, the Andronov–Pontryagin criterion. In this case, structurally stable systems are typical, they form an open dense set in the space of all systems endowed with appropriate topology. In higher dimensions, this is no longer true, indicating that typical dynamics can be very complex (cf strange attractor). An important class of structurally stable systems in arbitrary dimensions is given by Anosov diffeomorphisms and flows.In mathematics, structural stability is a fundamental property of a dynamical system which means that the qualitative behavior of the trajectories is unaffected by C1-small perturbations. Examples of such qualitative properties are numbers of fixed points and periodic orbits (but not their periods). Unlike Lyapunov stability, which considers perturbations of initial conditions for a fixed system, structural stability deals with perturbations of the system itself. Variants of this notion apply to systems of ordinary differential equations, vector fields on smooth manifolds and flows generated by them, and diffeomorphisms.The stability is one of the content which needs to be addressed in the design of steel structure engineering. Three are more engineering accident case due to the steel structure instability in the real life. For example,the stadium, in the city of Hartford 92 m by 110 m to the plane of space truss structure, suddenly fell on the ground in 1978. The reason is the compressive bar buckling instability;13.2 m by 18.0 m steel truss, in 1988,lack of stability of the web member collapsed in construction process in China;On January 3, 2010 in the afternoon, 38 m steel structure bridge in Kunming New across suddenly collapsed, killing seven people, 8 people seriously injured, 26 people slightly injured.The reason is that the bridge steel structure supporting system is out of stability, suddenly a bridge collapsing down to 8 m tall. We can see from the above case, the usual cause of instability and failure of steel structure is the unreasonable structural design, structural design defects.To fundamentally prevent such accidents, stability of steel structure design is the key.Structural stability of the system provides a justification for applying the qualitative theory of dynamical systems to analysis of concrete physical systems. The idea of such qualitative analysis goes back to the work of Henri Poincaré on the three-body problem in celestial mechanics. Around the same time, Aleksandr Lyapunov rigorously investigated stability of small perturbations of an individual system. In practice, the evolution law of the system (i.e. the differential equations) is neverknown exactly, due to the presence of various small interactions. It is, therefore, crucial to know that basic features of the dynamics are the same for any small perturbation of the "model" system, whose evolution is governed by a certain known physical law. Qualitative analysis was further developed by George Birkhoff in the 1920s, but was first formalized with introduction of the concept of rough system by Andronov and Pontryagin in 1937. This was immediately applied to analysis of physical systems with oscillations by Andronov, Witt, and Khaikin. The term "structural stability" is due to Solomon Lefschetz, who oversaw translation of their monograph into English. Ideas of structural stability were taken up by Stephen Smale and his school in the 1960s in the context of hyperbolic dynamics. Earlier, Marston Morse and Hassler Whitney initiated and René Thom developed a parallel theory of stability for differentiable maps, which forms a key part of singularity theory. Thom envisaged applications of this theory to biological systems. Both Smale and Thom worked in direct contact with Maurício Peixoto, who developed Peixoto's theorem in the late 1950's.When Smale started to develop the theory of hyperbolic dynamical systems, he hoped that structurally stable systems would be "typical". This would have been consistent with the situation in low dimensions: dimension two for flows and dimension one for diffeomorphisms. However, he soon found examples of vector fields on higher-dimensional manifolds that cannot be made structurally stable by an arbitrarily small perturbation (such examples have been later constructed on manifolds of dimension three). This means that in higher dimensions, structurally stable systems are not dense. In addition, a structurally stable system may have transversal homoclinic trajectories of hyperbolic saddle closed orbits and infinitely many periodic orbits, even though the phase space is compact. The closest higher-dimensional analogue of structurally stable systems considered by Andronov and Pontryagin is given by the Morse–Smale systems.Structure theory of stability study was conducted on the mathematical model of the ideal, and the actual structure is not as ideal as mathematical model, in fact ,we need to consider the influence of various factors. For example ,for the compressive rods, load could not have absolute alignment section center; There will always be some initial bending bar itself, the so-called "geometric defects"; Material itself inevitably has some kind of "defect", such as the discreteness of yield stress and bar manufacturing methods caused by the residual stress, etc. So, in addition to the modulus of elasticity and geometry size of bar, all the above-mentioned factors affecting the bearing capacity of the push rod in different degrees, in the structure design of this influence often should be considered. Usually will be based on the ideal mathematical model to study the stability of thetheory is called buckling theory, based on the actual bar study consider the various factors related to the stability of the stability of the ultimate bearing capacity theory called the theory ofcrushing.Practical bar, component or structure damage occurred during use or as the loading test of the buckling load is called crushing load and ultimate bearing capacity. For simplicity, commonly used buckling load. About geometric defects, according to a large number of experimental results, it is generally believed to assume a meniscus curve and its vector degrees for the rod length of 1/1000. About tissue defects, in the national standard formula is not the same, allow the buckling stress curve given by the very different also, some problems remain to be further research.1.Steel structure stability design concept1.1.The difference between intensity and stabilityThe intensity refers to that the structure or a single component maximum stress (or internal force)caused by load in stable equilibrium state is more than the ultimate strength of building materials, so it is a question of the stress. The ultimate strength value is different according to the characteristics of the material varies. for steel ,it is the yield point. The research of stability is mainly is to find the external load and structure unstable equilibrium between internal resistance. That is to say, deformation began to rapid growth and we should try to avoid the structure entering the state, so it is a question of deformation. For example, for an axial compression columns, in the condition column instability, the lateral deflection of the column add a lot of additional bending moment, thus the fracture load of pillars can be far less than its axial compression strength. At this point, the instability is the main reason of the pillar fracture .1.2.The classification of the steel structure instability1)The stability problem with the equilibrium bifurcation(Branch point instability).2)The axial compression buckling of the perfect straight rod and tablet compression bucklingall belong to this category.3)The stability of the equilibrium bifurcation problem(Extreme value point instability).4)The ability of the loss of stability of eccentric compression member made of constructionsteel in plastic development to a certain degree , fall into this category.5)Jumping instability6)Jumping instability is a kind of different from the above two types of stability problem. Itis a jump to another stable equilibrium state after loss of stability balance.2.The principle of steel structure stability design2.1.For the steel structure arrangement, the whole system and the stability of the part requirements must be considered ,and most of the current steel structure is designed according to plane system, such as truss and frame. The overall layout of structure can guarantee that the flat structure does not appear out-of-plane instability,such as increasing the necessary supporting artifacts, etc. A planar structures of plane stability calculation is consistent with the structure arrangement.2.2.Structure calculation diagram should be consistent with a diagram of a practical calculation method is based on. When designing a single layer or multilayer frame structure, we usually do not make analysis of the framework stability but the frame column stability calculation. When we use this method to calculate the column frame column stability , the length factor should be concluded through the framework of the overall stability analysis which results in the equivalent between frame column stability calculation and stability calculation. For a single layer or multilayer framework, the column length coefficient of computation presented by Specification for design of steel structures (GB50017-2003) base on five basic assumptions. Including:all the pillars in the framework is the loss of stability at the same time, that is ,the critical load of the column reach at the same time. According to this assumes, each column stability parameters of the frame and bar stability calculation method, is based on some simplified assumptions or typical.Designers need to make sure that the design of structure must be in accordance with these assumptions.2.3.The detail structure design of steel structure and the stable calculation of component should be consistent. The guarantee that the steel structure detail structure design and component conforms to the stability of the calculation is a problem that needs high attention in the design of steel structure.Bending moment tonon-transmission bending moment node connection should be assigned to their enough rigidity and the flexibility.Truss node should minimize the rods' bias.But, when it comes to stability, a structure often have different in strength or special consideration. But requirement above in solving the beam overall stability is not enough.Bearing need to stop beam around the longitudinal axis to reverse,meanwhile allowing the beam in thein-plane rotation and free warp beam end section to conform to the stability analysis of boundary conditions. 3.The analysis method of the steel structure stabilitySteel structure stability analysis is directed at the outer loads under conditions of the deformation of structure.The deformation should be relative to unstability deformation of the structure or buckling. Deformation between load and structure is nonlinear relationship , which belongs to nonlinear geometric stability calculation and uses a second order analysis method. Stability calculated, both buckling load and ultimate load, can be regarded as the calculation of the stability bearing capacity of the structure or component.In the elastic stability theory, the calculation method of critical force can be mainly divided into two kinds of static method and energy method.3.1.Static methodStatic method, both buckling load and ultimate load, can be regarded as the calculation of the stability bearing capacity of the structure or component. Follow the basic assumptions in establishing balance differential equation:1)Components such as cross section is a straight rod.2)Pressure function is always along the original axis component3)Material is in accordance with hooke's law, namely the linear relationship between thestress and strain.4)Component accords with flat section assumption, namely the component deformation infront of the flat cross-section is still flat section after deformation.5)Component of the bending deformation is small ant the curvature can be approximatelyrepresented by the second derivative of the deflection function.Based on the above assumptions, we can balance differential equation,substitude into the corresponding boundary conditions and solve both ends hinged the critical load of axial compression component .3.2.Energy methodEnergy method is an approximate method for solving stability bearing capacity, through the principle of conservation of energy and potential energy in principle to solve the critical load values.1)The principle of conservation of energy to solve the critical loadWhen conservative system is in equilibrium state, the strain energy storaged in the structure is equal to the work that the external force do, namely, the principle of conservation of energy. As thecritical state of energy relations:ΔU =ΔWΔU—The increment of strain energyΔW—The increment of work forceBalance differential equation can be established by the principle of conservation of energy.2)The principle of potential energy in value to solve the critical load valueThe principle of potential energy in value refers to: For the structure by external force, when there are small displacement but the total potential energy remains unchanged,that is, the total potential energy with in value, the structure is in a state of balance. The expression is:dΠ=dU-dW =0dU—The change of the structure strain energy caused by virtual displacement , it is always positive;dW—The work the external force do on the virtual displacement;3.3.Power dynamics methodMany parts of the qualitative theory of differential equations and dynamical systems deal with asymptotic properties of solutions and the trajectories—what happens with the system after a long period of time. The simplest kind of behavior is exhibited by equilibrium points, or fixed points, and by periodic orbits. If a particular orbit is well understood, it is natural to ask next whether a small change in the initial condition will lead to similar behavior. Stability theory addresses the following questions: will a nearby orbit indefinitely stay close to a given orbit? will it converge to the given orbit (this is a stronger property)? In the former case, the orbit is called stable and in the latter case, asymptotically stable, or attracting. Stability means that the trajectories do not change too much under small perturbations. The opposite situation, where a nearby orbit is getting repelled from the given orbit, is also of interest. In general, perturbing the initial state in some directions results in the trajectory asymptotically approaching the given one and in other directions to the trajectory getting away from it. There may also be directions for which the behavior of the perturbed orbit is more complicated (neither converging nor escaping completely), and then stability theory does not give sufficient information about the dynamics.One of the key ideas in stability theory is that the qualitative behavior of an orbit under perturbations can be analyzed using the linearization of the system near the orbit. In particular, at each equilibrium of a smooth dynamical system with an n-dimensional phase space, there is acertain n×n matrix A whose eigenvalues characterize the behavior of the nearby points (Hartman-Grobman theorem). More precisely, if all eigenvalues are negative real numbers or complex numbers with negative real parts then the point is a stable attracting fixed point, and the nearby points converge to it at an exponential rate, cf Lyapunov stability and exponential stability. If none of the eigenvalues is purely imaginary (or zero) then the attracting and repelling directions are related to the eigenspaces of the matrix A with eigenvalues whose real part is negative and, respectively, positive. Analogous statements are known for perturbations of more complicated orbits.For the structure system in balance,if making it vibrate by applying small interference vibration,the structure of the deformation and vibration acceleration is relation to the structure load. When the load is less than the limit load of a stable value, the acceleration and deformation is in the opposite direction, so the interference is removed, the sports tend to be static and the structure of the equilibrium state is stable; When the load is greater than the ultimate load of stability, the acceleration and deformation is in the same direction, even to remove interference, movement are still divergent, therefore the structure of the equilibrium state is unstable. The critical state load is the buckling load of the structure,which can be made of the conditions that the structure vibration frequency is zero solution.At present, a lot of steel structure design with the aid of computer software for structural steel structure stress calculation, structure and component within the plane of strength and the overall stability calculation program automatically, can be counted on the structure and component of the out-of-plane strength and stability calculation, designers need to do another analysis, calculation and design. At this time the entire structure can be in the form of elevation is decomposed into a number of different layout structure, under different levels of load, the structure strength and stability calculation.local stability after buckling strength of the beam, it can be set up to the beam transverse or longitudinal stiffener, in order to solve the problem, the local stability of the beam stiffening rib according to Specification for Design of Steel Structures (GB50017-2003) ; Finite element analysis for a web after buckling strength calculation according to specification for design of steel structures (GB50017-2003) 4, 4 provisions. Axial compression member and a local bending component has two ways: one is the control board free overhanging flange width and thickness ratio of; The second is to control web computing the ratio of the height and thickness. For circular tube sectioncompression member, should control the ratio of outer diameter and wall thickness and stiffener according to specification for design of steel structures (GB50017-2003), 5 4 rule.4.ConclusionSteel structure has advantages of light weight, high strength and high degree of industrialization and has been widely used in the construction engineering.I believe that through to strengthen the overall stability and local stability of the structure and the design of out-of-plane stability, we could overcome structure design flaws and its application field will be more and more widely.referencesGB50017-2003,Design Code for Steel Structures[S]Chen Shaofan, Steel structure design principle [M]. Beijing: China building industry press, 2004 Kalman R.E. & Bertram J.F: Control System Analysis and Design via the Second Method of Lyapunov, J. Basic Engrg vol.88 1960 pp.371; 394LaSalle J.P. & Lefschetz S: Stability by Lyapunov's Second Method with Applications, New York 1961 (Academic)Smith M.J. and Wisten M.B., A continuous day-to-day traffic assignment model and the existence of a continuous dynamic user equilibrium , Annals of Operations Research, V olume 60, 1995 Arnold, V. I. (1988). Geometric methods in the theory of differential equations. Grundlehren der Mathematischen Wissenschaften, 250. Springer-Verlag, New York. ISBN 0-387-96649-8 Structural stability at Scholarpedia, curated by Charles Pugh and Maurício Matos Peixoto.。

钢结构毕业设计

钢结构毕业设计

前言伴随着我国经济与科学技术的快速发展,钢结构已逐步在工业厂房,商业大楼,民用住宅,大型场馆等公共建筑中被广泛采用。

钢材的强度高,故在结构中占体积小,因而建筑的实用空间就较大;钢结构可以成套预制装配,故施工方便;钢材可以回炉重新利用,故钢结构的再生性好。

钢结构有着非常多的优点,我国的钢结构事业也正处在蓬勃发展中。

轻型钢结构除具有普通钢结构的材质均匀,可靠性高;强度高,重量轻;塑性韧性,抗震性能好;便于机械化制造,施工期短;可回收,建筑造型美观等特点以外,一般还具有取材方便,用料较省,自重更轻等特点。

它对加快基本建设速度,特别对中小型企业的建设,以及对现有企业的挖潜、革新、改造等工作能够起到显著的作用,因而受到建设单位,尤其是在工业建筑中的普遍欢迎。

由于轻型钢结构的经济指标很好,总造价较低,再加上结构自重轻为改革重型结构体系创造了条件。

因此,轻型钢结构是很有发展前途的一种结构形势。

基于以上对轻型钢结构的认识,我在毕业设计课题中选择了轻型钢结构设计。

本次设计的是万利集团民用工业园的轻钢结构房屋工程。

通过这次设计,我希望能对钢结构的计算原理、轻型钢结构的特点和构造要求有一个较系统的认识。

同时,通过这次设计,培养自己理论结合实践的能力,积累工程经验,从而为将来走向工作岗位打下坚实的基础。

摘要近年来,轻钢结构因其取材方便、用料省、自重轻、构件批量生产、现场施工速度快、周期短等诸多特点,在我国取得了长足的发展。

其中,门式刚架造型由于其简洁美观、平面布置灵活、安装便利及可以满足多种生产工艺和使用功能的要求等特点,目前正被运用于越来越多的钢结构房屋建筑中。

本工程是以轻型门式钢架作为结构形式的单层工业厂房。

厂房共有两跨,每跨设有两台桥式软钩吊车。

厂房为双坡屋面,除基础和地基梁使用混凝土、外墙标高以下为240厚砖墙外,其他所有主次要构件均为钢结构。

首先根据现有资料进行建筑方案的比选及建筑的平、立、剖面的设计;然后建筑设计基础之上的结构布置、静力计算、框架设计、节点设计、柱脚设计、檩条设计、柱间支撑设计、吊车梁设计及基础设计等。

钢结构厂房开题报告加外文翻译

钢结构厂房开题报告加外文翻译

南京理工大学毕业设计(论文)开题报告学生姓名:邓逸欣学号:532110140301专业:土木工程设计(论文)题目:仁厚重型加工车间设计指导教师:惠颖2015年12月02日开题报告填写要求1.开题报告作为毕业设计(论文)答辩委员会对学生答辩资格审查的依据材料之一。

此报告应在指导教师指导下,由学生在毕业设计(论文)工作前期内完成,经指导教师签署意见及所在专业审查后生效;2.开题报告内容必须用黑墨水笔工整书写或按教务处统一设计的电子文档标准格式(可从继续教育学院网站上下载)打印,禁止打印在其它纸上后剪贴,完成后应及时交给指导教师签署意见;3.“文献综述”应按论文的格式成文,并直接书写(或打印)在本开题报告第一栏目内,学生写文献综述的参考文献应不少于15篇(不包括辞典、手册);4.有关年月日等日期的填写,应当按照国标GB/T 7408—2005《数据元和交换格式、信息交换、日期和时间表示法》规定的要求,一律用阿拉伯数字书写。

如“2007年3月15日”或“2007-03-15”。

毕业设计(论文)开题报告仁厚重型加工车间设计摘要本设计为轻型钢结构厂房,采用轻型门式刚架体系,轻型钢结构建筑质量轻,强度高,跨度大,钢结构建筑施工工期短,相应降低投资成本,经济实惠。

它在我国有着较为广泛的应用前景。

轻型钢结构的屋面荷载较轻,因而杆件截面较小、较薄。

它除具有普通钢结构的自重较轻、材质均匀、应力计算准确可靠、加工制造简单、工业化程度高、运输安装方便等特点外,一般还具有取材方便、用料较省、自重更轻等优点。

本设计说明书包括建筑设计,结构设计两部分。

建筑设计部分具体为建筑平面形式的选择,厂房剖面设计,厂房立面设计,厂房的构造设计,门窗明细表。

结构设计部分包括方案选择,吊车梁设计,檩条设计,抗风柱设计,牛腿设计,刚架设计(内力组合),节点设计。

各章节都详细演算了主要构件的计算过程。

本次设计图纸部分有:厂房平面图,立面剖面及节点详图,刚架施工图,厂房檩条墙梁布置图,吊车梁施工图,支撑布置图,基础平面布置图。

钢结构毕业设计

钢结构毕业设计

钢结构毕业设计毕业设计(论文)课题名称接头焊缝的设计系别土木系专业建筑工程技术班级08级统招专科建筑工程技术一班姓名学号指导老师毕业设计(论文)任务书系土木系专业建筑工程技术年级大三班级08统招专科建筑工程技术一班姓名起止日期2022年1月3日至2月3日设计题目设计角钢连接的角焊缝1.毕业设计(论文)任务及要求(包括设计或论文的主要内容、主要技术指标,并根据题目性质对学生提出具体要求)本文介绍在不同角焊缝连接方式的等边角钢,根据被焊构件承受的轴力计算出每种连接方式的焊缝应力值并进行验算。

关键词:等边角钢、轴力、侧面角焊缝、L型围焊连接、三面围焊连接使用两根等边的角钢L110某10和强度为Q235的搭接板用角焊缝连接起来,如下图所示,焊接方法为手工焊,所用焊条为E43型。

根据构造要求和强度要求并按照侧面角焊缝、L型围焊连接和三面围焊连接三种角焊缝的连接方式设计出角焊缝的焊角尺寸与长度,被焊构件所受的轴力为700kN。

在设计过程中须写出完整的计算书,详细算出各种脚焊缝连接下各条焊缝上的应力值并进行强度验算。

1、刚结构,钟山桐,武汉大学出版社2、钢结构原理与设计(精编本),刘声扬等,武汉理工大学出版社3、钢结构,魏明钟,武汉理工大学出版社4、钢结构基本原理,沈祖炎等,中国建筑工业出版社指导教师年月日2指导教师评语建议成绩:优良中及格不及格指导教师签字3年月日最终评定成绩:优良中及格不及格系主任签字年月日4目录打印格式目录绪言5一、钢结构的角焊缝6(一)、角钢与钢板用角焊缝的连接形式61、两个侧面焊缝2、三面围焊3、L形围焊(二)、计算角焊缝的长度61、对于两面侧焊2、对于三面围焊3、当杆件受力很小时,可采用L形围焊。

二、角焊缝受轴心力作用的计算8(一)、侧面角焊缝或作用力平行于焊缝长度方向的角焊缝8(二)、正面角焊缝或作用力与焊缝长度方向垂直的角焊缝8三、按照不同形式的角焊缝连接根据构造要求和强度要求设计出角焊缝的焊脚尺寸与长度,并算出各条焊缝上的应力值进行强度验算8(一)、侧面角焊接81、计算焊脚尺寸和长度2、各条焊缝上的强度验算(二)、三面围焊91、计算焊角尺寸和长度2、各条焊缝上的强度验算(三)、L形围焊101、计算焊角尺寸和长度2、各条焊缝上的强度验算四、总结11五、参考文献125正文打印格式1.字号:标题的字号:一、小三、加粗。

钢结构桥梁中英文对照外文翻译文献

钢结构桥梁中英文对照外文翻译文献

中英文对照外文翻译文献(文档含英文原文和中文翻译)Recent Research and Design Developments in Steel and Composite Steel-concrete Structures in USAThe paper will conclude with a look toward the future of structural steel research.1. Research on steel bridgesThe American Association of State Transportation and Highway Officials (AASTHO) is the authority that promulgates design standards for bridges in the US. In 1994 it has issued a new design specification which is a Limit States Design standard that is based on the principles of reliability theory. A great deal of work went into the development of this code in the past decade, especially on calibration and on the probabilistic evaluation of the previous specification. The code is now being implemented in the design office, together with the introduction of the SystemeInternationale units. Many questions remain open about the new method of design, and there are many new projects that deal with the reliability studies of the bridge as a system. One such current project is a study to develop probabilistic models, load factors, and rational load-combination rules for the combined effects of live-load and wind; live-load and earthquake; live-load, wind and ship collision; and ship collision, wind, and scour. There are also many field measurements of bridge behavior, using modern tools of inspection and monitoring such as acoustic emission techniques and other means of non-destructive evaluation. Such fieldwork necessitates parallel studies in the laboratory, and the evolution of ever more sophisticated high-technology data transmission methods.America has an aging steel bridge population and many problems arise from fatigue and corrosion. Fatigue studies on full-scale components of the Williamsburg Bridge in New York have recently been completed at Lehigh University. A probabilistic AASTHO bridge evaluation regulation has been in effect since 1989, and it is employed to assess the future useful life of structures using rational methods that include field observation and measurement together with probabilistic analysis. Such an activity also fosters additional research because many issues are still unresolved. One such area is the study of the shakedown of shear connectors in composite bridges. This work has been recently completed at the University of Missouri.In addition to fatigue and corrosion, the major danger to bridges is the possibility of earthquake induced damage. This also has spawned many research projects on the repair and retrofit of steel superstructures and the supporting concrete piers. Many bridges in the country are being strengthened for earthquake resistance. One area that is receiving much research attention is the strengthening of concrete piers by "jacketing" them by sheets of high-performance reinforced plastic.The previously described research deals mainly with the behavior of existing structures and the design of new bridges. However, there is also a vigorous activity on novel bridge systems. This research is centered on the application of high-performance steels for the design of innovative plate and box-girder bridges, such as corrugated webs, combinations of open and closed shapes, and longer spansfor truss bridges. It should be mentioned here that, in addition to work on steel bridges, there is also very active research going on in the study of the behavior of prestressed concrete girders made from very high strength concrete. The performance and design of smaller bridges using pultruded high-performance plastic composite members is also being studied extensively at present. New continuous bridge systems with steel concrete composite segments in both the positive moment and the negative moment regions are being considered. Several researchers have developed strong capabilities to model the three-dimensional non-linear behavior of individual plate girders, and many studies are being performed on the buckling and post-buckling characteristics of such panion experimental studies are also made,especially on members built from high-performance steels. A full-scale bridge of such steel has been designed, and will soon be constructed and then tested under traffic loading. Research efforts are also underway on the study of the fatigue of large expansion joint elements and on the fatigue of highway sign structures.The final subject to be mentioned is the resurgence of studies of composite steel concrete horizontally curved steel girder bridges. A just completed project at the University of Minnesota monitored the stresses and the deflections in a skewed and curved bridge during all phases of construction, starting from the fabrication yard to the completed bridge.~ Excellent correlation was found to exist between the measured stresses and deformations and the calculated values. The stresses and deflections during construction were found to be relatively small, that is, the construction process did not cause severe trauma to the system. The bridge has now been tested under service loading, using fully loaded gravel trucks, for two years, and it will continue to be studied for further years to measure changes in performance under service over time. A major testing project is being conducted at the Federal Highway Administration laboratory in Washington, DC, where a half-scale curved composite girder bridge is currently being tested to determine its limit states. The test-bridge was designed to act as its own test-frame, where various portions can be replaced after testing. Multiple flexure tests, shear tests, and tests under combined bending and shear, are thus performed with realistic end-conditions and restraints. The experiments arealso modeled by finite element analysis to check conformance between reality and prediction. Finally design standards will be evolved from the knowledge gained. This last project is the largest bridge research project in the USA at the present time.From the discussion above it can be seen that even though there is no large expansion of the nation's highway and railroad system, there is extensive work going on in bridge research. The major challenge facing both the researcher and the transportation engineer is the maintenance of a healthy but aging system, seeing to its gradual replacement while keeping it safe and serviceable.2. Research on steel members and framesThere are many research studies on the strength and behavior of steel building structures. The most important of these have to do with the behavior and design of steel structures under severe seismic events. This topic will be discussed later in this paper. The most significant trends of the non-seismic research are the following: "Advanced" methods of structural analysis and design are actively studied at many Universities, notably at Cornell, Purdue, Stanford, and Georgia Tech Universities. Such analysis methods are meant to determine the load-deformation behavior of frames up to and beyond failure, including inelastic behavior, force redistribution, plastic hinge formation, second-order effects and frame instability. When these methods are fully operational, the structure will not have to undergo a member check, because the finite element analysis of the frame automatically performs this job. In addition to the research on the best approaches to do this advanced analysis, there are also many studies on simplifications that can be easily utilized in the design office while still maintaining the advantages of a more complex analysis. The advanced analysis method is well developed for in-plane behavior, but much work is yet to be done on the cases where bi-axial bending or lateraltorsional buckling must be considered. Some successes have been achieved, but the research is far from complete.Another aspect of the frame behavior work is the study of the frames with semirigid joints. The American Institute of Steel Construction (AISC) has published design methods for office use. Current research is concentrating on the behavior ofsuch structures under seismic loading. It appears that it is possible to use such frames in some seismic situations, that is, frames under about 8 to 10 stories in height under moderate earthquake loads. The future of structures with semi-rigid frames looks very promising, mainly because of the efforts of researchers such as Leon at Georgia Tech University, and many others.Research on member behavior is concerned with studying the buckling and post buckling behavior of compact angle and wide-flange beam members by advanced commercial finite element programs. Such research is going back to examine the assumptions made in the 1950s and 1960s when the plastic design compactness and bracing requirements were first formulated on a semi-empirical basis. The non-linear finite element computations permit the "re-testing" of the old experiments and the performing of new computer experiments to study new types of members and new types of steels. White of Georgia Tech is one of the pioneers in this work. Some current research at the US military Academy and at the University of Minnesota by Earls is discussed later in this report. The significance of this type of research is that the phenomena of extreme yielding and distortion can be efficiently examined in parameter studies performed on the computer. The computer results can be verified with old experiments, or a small number of new experiments. These studies show a good prospect fornew insights into old problems that heretofore were never fully solved.3. Research on cold-formed steel structuresNext to seismic work, the most active part of research in the US is on cold-formed steel structures. The reason for this is that the supporting industry is expanding, especially in the area of individual family dwellings. As the cost of wood goes up, steel framed houses become more and more economical. The intellectual problems of thin-walled structures buckling in multiple modes under very large deformations have attracted some of the best minds in stability research. As a consequence, many new problems have been solved: complex member stiffening systems, stability and bracing of C and Z beams, composite slabs, perforated columns, standing-seam roof systems, bracing and stability of beams with very complicatedshapes, cold-formed members with steels of high yield stress-to-tensile strength ratio, and many other interesting applications. The American Iron and Steel Institute (AISI) has issued a new expanded standard in 1996 that brought many of these research results into the hands of the designer.4. Research on steel-concrete composite structuresAlmost all structural steel bridges and buildings in the US are built with composite beams or girders. In contrast, very few columns are built as composite members. The area of composite Column research is very active presently to fill up the gap of technical information on the behavior of such members. The subject of steel tubes filled with high-strength concrete is especially active. One of the aims of research performed by Hajjar at the University of Minnesota is to develop a fundamental understanding of the various interacting phenomena that occur in concrete-filled columns and beam-columns under monotonic and cyclic load. The other aim is to obtain a basic understanding of the behavior of connections of wide-flange beams to concrete filled tubes.Other major research work concerns the behavior and design of built-up composite wide-flange bridge girders under both positive and negative bending. This work is performed by Frank at the University of Texas at Austin and by White of Georgia Tech, and it involves extensive studies of the buckling and post-buckling of thin stiffened webs. Already mentioned is the examination of the shakedown of composite bridges. The question to be answered is whether a composite bridge girder loses composite action under repeated cycles of loads which are greater than the elastic limit load and less than the plastic mechanism load. A new study has been initiated at the University of Minnesota on the interaction between a semi-rigid steel frame system and a concrete shear wall connected by stud shear connectors.5. Research on connectionsConnection research continues to interest researchers because of the great variety of joint types. The majority of the connection work is currently related to the seismic problems that will be discussed in the next section of this paper. The most interest in non-seismic connections is the characterization of the monotonic moment-rotationbehavior of various types of semi-rigid joints.6. Research on structures and connections subject to seismic forcesThe most compelling driving force for the present structural steel research effort in the US was the January 17, 1994 earthquake in Northridge, California, North of Los Angeles. The major problem for steel structures was the extensive failure of prequalified welded rigid joints by brittle fracture. In over 150 buildings of one to 26 stories high there were over a thousand fractured joints. The buildings did not collapse, nor did they show any external signs of distress, and there were no human injuries or deaths. A typical joint is shown in Fig. 2.2.1.In this connection the flanges of the beams are welded to the flanges of the column by full-penetration butt welds. The webs are bolted to the beams and welded to the columns. The characteristic features of this type of connection are the backing bars at the bottom of the beam flange, and the cope-holes left open to facilitate the field welding of the beam flanges. Fractures occurred in the welds, in the beam flanges, and/or in the column flanges, sometimes penetrating into the webs.Once the problem was discovered several large research projects were initiated at various university laboratories, such as The University of California at San Diego, the University of Washington in Seattle, the University of Texas at Austin, Lehigh University at Bethlehem, Pennsylvania, and at other places. The US Government under the leadership of the Federal Emergency Management Agency (FEMA) instituted a major national research effort. The needed work was deemed so extensivethat no single research agency could hope to cope with it. Consequently three California groups formed a consortium which manages the work:(1) Structural Engineering Association of California.(2) Applied Technology Council.(3) California Universities for Research in Earthquake Engineering.The first letters in the name of each agency were combined to form the acronym SAC, which is the name of the joint venture that manages the research. We shall read much from this agency as the results of the massive amounts of research performed under its aegis are being published in the next few years.The goals of the program are to develop reliable, practical and cost-effective guidelines for the identification and inspection of at-risk steel moment frame buildings, the repair or upgrading of damaged buildings, the design of new construction, and the rehabilitation of undamaged buildings.~ As can be seen, the scope far exceeds the narrow look at the connections only. The first phase of the research was completed at the end of 1996, and its main aim was to arrive at interim guidelines so that design work could proceed. It consisted of the following components:~ A state-of-the-art assessment of knowledge on steel connections.~ A survey of building damage.~ The evaluation of ground motion.~ Detailed building analyses and case studies.~ A preliminary experimental program.~ Professional training and quality assurance programs.~ Publishing of the Interim Design Guidelines.A number of reports were issued in this first phase of the work. A partial list of these is appended at the end of this paper.During the first phase of the SAC project a series of full-scale connection tests under static and, occasionally, dynamic cyclic tests were performed. Tests were of pre-Northridge-type connections (that is, connections as they existed at the time of the earthquake), of repaired and upgraded details, and of new recommendedconnection details. A schematic view of the testing program is illustrated in Fig.2.2.2 Some recommended strategies for new design are schematically shown in Fig. 2.2.3.Fig. 2.2.3 some recommended improvements in the interim guidelinesThe following possible causes, and their combinations, were found to have contributed to tile connection failures:~ Inadequate workmanship in the field welds.~ Insufficient notch-toughness of the weld metal.~ Stress raisers caused by the backing bars.~ Lack of complete fusion near the backing bar.~ Weld bead sizes were too big.~ Slag inclusion in the welds.While many of the failures can be directly attributed to the welding and thematerial of the joints, there are more serious questions relative to the structural system that had evolved over the years mainly based on economic considerations.' The structural system used relatively few rigid-frames of heavy members that were designed to absorb the seismic forces for large parts of the structure. These few lateral-force resistant frames provide insufficient redundancy. More rigid-frames with smaller members could have provided a tougher and more ductile structural system. There is a question of size effect: Test results from joints of smaller members were extrapolated to joints with larger members without adequate test verification. The effect of a large initial pulse may have triggered dynamic forces that could have caused brittle fracture in joints with fracture critical details and materials. Furthermore, the yield stress of the beams was about 30% to 40% larger than the minimum specified values assumed in design, and so the connection failed before the beams, which were supposed to form plastic hinges.As can be seen, there are many possible reasons for this massive failure rate, and there is blame to go around for everyone. No doubt, the discussion about why and how the joints failed will go on for many more years. The structural system just did not measure up to demands that were more severe than expected. What should be kept in mind, however, is that no structure collapsed or caused even superficial nonstructural damage, and no person was injured or killed. In the strictest sense the structure sacrificed itself so that no physical harm was done to its users. The economic harm, of course, was enormous.7. Future directions of structural steel research and conclusionThe future holds many challenges for structural steel research. The ongoing work necessitated by the two recent earthquakes that most affected conventional design methods, namely, the Northridge earthquake in the US and the Kobe earthquake in Japan, will continue well into the first decade of the next Century. It is very likely that future disasters of this type will bring yet other problems to the steel research community. There is a profound change in the philosophy of design for disasters: We can no longer be content with saving lives only, but we must also design structures which will not be so damaged as to require extensive repairs.Another major challenge will be the emergence of many new materials such as high-performance concrete and plastic composite structures. Steel structures will continually have to face the problem of having to demonstrate viability in the marketplace. This can only be accomplished by more innovative research. Furthermore, the new comprehensive limit-states design codes which are being implemented worldwide, need research to back up the assumptions used in the theories.Specifically, the following list highlights some of the needed research in steel structures:Systems reliability tools have been developed to a high degree of sophistication. These tools should be applied to the studies of bridge and building structures to define the optimal locations of monitoring instruments, to assess the condition and the remaining life of structures, and to intelligently design economic repair and retrofit operations.New developments in instrumentation, data transfer and large-scale computation will enable researchers to know more about the response of structures under severe actions, so that a better understanding of "real-life" behavior can be achieved.The state of knowledge about the strength of structures is well above the knowledge about serviceability and durability. Research is needed on detecting and preventing damage in service and from deterioration.The areas of fatigue and fracture mechanics on the one hand, and the fields of structural stability on the other hand, should converge into a more Unified conceptual entity.The problems resulting from the combination of inelastic stability and low-cycle fatigue in connections subject to severe cyclic loads due to seismic action will need to be solved.The performance of members, connections and connectors (e.g., shear connectors) under severe cyclic and dynamic loading requires extensive new research, including shakedown behavior.The list could go on, but one should never be too dogmatic about the future ofsuch a highly creative activity as research. Nature, society and economics will provide sufficient challenges for the future generation of structural engineers.近期美国在钢结构和钢筋混凝土结构研究和设计方面的发展这篇文章将总结对钢结构的研究展望.1.钢结构桥梁的研究美国国家运输和公路官员协会(AASTH0)是为美国桥梁发布设计标准的权威。

钢结构毕业设计论文

钢结构毕业设计论文摘要:钢结构作为一种重要的建筑结构形式,在现代建筑领域得到了广泛应用。

本文主要研究了钢结构的设计原理、施工工艺以及相关的优缺点,通过实际案例分析探讨了钢结构在建筑中的应用和发展趋势。

通过对钢结构的研究和分析可以发现,钢结构具有高强度、抗震、可塑性好等优点,但也存在着腐蚀、施工难度大等缺点。

因此,钢结构在设计和施工过程中需要加以合理的考虑和应用。

关键词:钢结构、设计原理、施工工艺、优缺点、应用、发展趋势1、引言钢结构是以钢材为主要材料,通过连接构件组成的一种建筑结构形式。

钢结构具有很高的强度、刚度和稳定性,广泛应用于各类建筑中。

本文通过研究钢结构的设计原理和施工工艺,分析了钢结构在建筑中的应用和发展趋势。

2、钢结构的设计原理2.1强度设计原理钢结构的强度设计原理是基于材料的力学性能和结构的受力规律。

根据结构的荷载特点和强度要求,采用适当的钢材和截面形状,通过计算和验算确定各构件的强度和稳定性。

2.2刚度设计原理刚度设计原理是指通过控制结构的刚度,使结构在受力过程中不会产生过大的变形和挠度。

刚度设计主要考虑结构的刚度比例、节点设计和连接设计等因素,以保证结构的稳定和耐久性。

3、钢结构的施工工艺3.1组装式施工工艺组装式施工工艺是指将钢构件在生产厂家进行预制后,通过运输和组装的方式进行建筑施工。

这种施工工艺可以提高施工效率和质量,减少工期和人力投入。

3.2简支梁施工工艺简支梁施工工艺是指将钢梁作为支撑结构,在搭设好临时支架后进行钢梁的安装和连接。

这种施工工艺适用于较长、较大跨度的梁结构,能够确保钢梁的水平度和稳定性。

4、钢结构的优缺点4.1优点钢结构具有高强度、抗震和可塑性好的特点,能够承受较大的荷载和变形。

此外,钢结构的施工周期短,能够提高建筑工程的进度和效率。

4.2缺点钢结构容易受到腐蚀的影响,需要进行防腐处理。

同时,钢结构的施工难度大,需要专业的人员进行施工和监督。

5、钢结构在建筑中的应用和发展趋势钢结构在高层建筑、工业厂房等领域得到了广泛应用。

高层结构与钢结构(中英论文翻译用)

高层结构与钢结构(中英论文翻译用) - 建筑技术高层结构与钢结构近年来,尽管一般的建筑结构设计取得了很大的进步,但是取得显著成绩的还要属超高层建筑结构设计。

最初的高层建筑设计是从钢结构的设计开始的。

钢筋混凝土和受力外包钢筒系统运用起来是比较经济的系统,被有效地运用于大批的民用建筑和商业建筑中。

50层到100层的建筑被定义为超高层建筑。

而这种建筑在美国得广泛的应用是由于新的结构系统的发展和创新。

这样的高度需要增大柱和梁的尺寸,这样以来可以使建筑物更加坚固以至于在允许的限度范围内承受风荷载而不产生弯曲和倾斜。

过分的倾斜会导致建筑的隔离构件、顶棚以及其他建筑细部产生循环破坏。

除此之外,过大的摇动也会使建筑的使用者们因感觉到这样的的晃动而产生不舒服的感觉。

无论是钢筋混凝土结构系统还是钢结构系统都充分利用了整个建筑的刚度潜力,因此不能指望利用多余的刚度来限制侧向位移。

在钢结构系统设计中,经济预算是根据每平方英寸地板面积上的钢材的数量确定的。

图示1中的曲线A显示了常规框架的平均单位的重量随着楼层数的增加而增加的情况。

而曲线B显示则显示的是在框架被保护而不受任何侧向荷载的情况下的钢材的平均重量。

上界和下界之间的区域显示的是传统梁柱框架的造价随高度而变化的情况。

而结构工程师改进结构系统的目的就是减少这部分造价。

钢结构中的体系:钢结构的高层建筑的发展是几种结构体系创新的结果。

这些创新的结构已经被广泛地应用于办公大楼和公寓建筑中。

刚性带式桁架的框架结构:为了联系框架结构的外柱和内部带式桁架,可以在建筑物的中间和顶部设置刚性带式桁架。

1974年在米望基建造的威斯康森银行大楼就是一个很好的例子。

框架筒结构:如果所有的构件都用某种方式互相联系在一起,整个建筑就像是从地面发射出的一个空心筒体或是一个刚性盒子一样。

这个时候此高层建筑的整个结构抵抗风荷载的所有强度和刚度将达到最大的效率。

这种特殊的结构体系首次被芝加哥的43层钢筋混凝土的德威特红棕色的公寓大楼所采用。

关于钢结构的英文作文

关于钢结构的英文作文英文:Steel structure is a popular choice for building construction due to its many advantages. Firstly, it is durable and can withstand harsh weather conditions and natural disasters such as earthquakes and hurricanes. This is because steel is a strong and flexible material that can absorb shock and resist deformation. Secondly, steel structures are easy to assemble and disassemble, making them ideal for temporary or mobile buildings such as exhibition halls or warehouses. Thirdly, steel is a sustainable material that can be recycled and reused, reducing waste and environmental impact.In addition, steel structures offer design flexibility and can be customized to meet specific requirements. For example, the shape and size of the structure can be adjusted to fit the available space and the intended use of the building. Moreover, steel structures can be combinedwith other materials such as glass, wood or concrete to create a unique and aesthetically pleasing design.However, there are also some challenges associated with steel structure construction. One of the main challenges is corrosion, which can weaken the structure over time. This can be prevented by applying protective coatings or using stainless steel. Another challenge is the cost, as steel structures can be more expensive than traditional building materials such as wood or brick. However, the long-term benefits of durability and sustainability may outweigh the initial cost.Overall, steel structure construction offers many advantages and is a viable option for building projects of various sizes and purposes.中文:钢结构是建筑施工中一个受欢迎的选择,因为它有许多优点。

土木工程专业毕业论文钢结构设计

土木工程专业毕业论文钢结构设计钢结构设计是土木工程专业中非常重要的一个方向。

随着工业化和城市化的发展,钢结构建筑在现代建筑中扮演着重要的角色。

本篇论文将讨论钢结构设计的关键问题,包括钢材的选择、结构设计方法和构造设计等方面。

首先,钢材的选择是钢结构设计中的一个关键问题。

钢材的性能直接影响到结构的安全性和经济性。

在选择钢材时,需要考虑到结构的受力情况、材料的强度和韧性等因素。

例如,在承受大荷载和较高应力的部位,需要选择高强度钢材;而在需要有一定韧性和可塑性的部位,需要选择韧性较好的钢材。

此外,还需要考虑到钢材的耐腐蚀性、耐火性和施工性能等因素。

因此,钢材的选择是钢结构设计中不可忽视的一个重要环节。

其次,在钢结构设计中,结构设计方法的选择也是一个关键问题。

结构设计方法的选择应基于结构的受力特点和要求。

例如,在正规的建筑中,常采用荷载法进行结构设计,即根据建筑使用要求和相关规范确定各个荷载的作用形式和大小,然后根据受力平衡条件进行结构计算。

而在一些特殊的结构中,如高层建筑和大跨度结构,则需要采用更为精细的分析方法,包括弹性分析、弹塑性分析和非线性分析等。

此外,还需要考虑到结构的抗震性和抗风性等因素。

最后,在钢结构设计中,构造设计也是一个重要环节。

构造设计涉及到结构的节点设计、连接设计和支承设计等。

在节点设计中,需要考虑到力的传递、材料的连接和结构的变形等因素。

在连接设计中,需要考虑到连接的强度、刚度和耐久性等。

在支承设计中,需要考虑到结构的稳定性和刚度等。

因此,构造设计需要综合考虑结构的力学性能和施工性能等因素。

综上所述,钢结构设计是土木工程专业中一个重要的方向。

钢结构设计涉及到钢材的选择、结构设计方法和构造设计等关键问题。

钢结构设计的质量直接影响到建筑的安全性和经济性。

因此,钢结构设计人员需要具备扎实的专业知识和丰富的实践经验,以保证结构设计的准确性和可靠性。

同时,钢结构设计人员还需要与各个相关专业进行密切的合作,以解决结构设计中的各种问题。

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浅谈钢结构现在,钢以一种或者形式逐渐成为全球应用最广泛的建筑材料。

对于建筑构架,除了很特殊的工程之外,钢材几乎已经完全取代了木材,总的来说,对于桥梁和结构骨架,钢也逐渐代替了铸铁和炼铁。

最为现代最重要的建筑材料,钢是在19世纪被引入到建筑中的,钢实质上是铁和少量碳的合金,一直要通过费力的过程被制造,所以那时的钢仅仅被用在一些特殊用途,例如制造剑刃。

1856年贝塞麦炼钢发发明以来,刚才能以低价大量获得。

刚最显著的特点就是它的抗拉强度,也就是说,当作用在刚上的荷载小于其抗拉强度荷载时,刚不会失去它的强度,正如我们所看到的,而该荷载足以将其他材料都拉断。

新的合金又进一步加强了钢的强度,与此同时,也消除了一些它的缺陷,比如疲劳破坏。

钢作为建筑材料有很多优点。

在结构中使用的钢材成为低碳钢。

与铸铁相比,它更有弹性。

除非达到弹性极限,一旦巴赫在曲调,它就会恢复原状。

即使荷载超出弹性和在很多,低碳钢也只是屈服,而不会直接断裂。

然而铸铁虽然强度较高,却非常脆,如果超负荷,就会没有征兆的突然断裂。

钢在拉力(拉伸)和压力作用下同样具有高强度这是钢优于以前其他结构金属以及砌砖工程、砖石结构、混凝土或木材等建筑材料的优点,这些材料虽然抗压,但却不抗拉。

因此,钢筋被用于制造钢筋混凝土——混凝土抵抗压力,钢筋抵抗拉力。

在钢筋框架建筑中,用来支撑楼板和墙的水平梁也是靠竖向钢柱支撑,通常叫做支柱,除了最底层的楼板是靠地基支撑以外,整个结构的负荷都是通过支柱传送到地基上。

平屋面的构造方式和楼板相同,而坡屋顶是靠中空的钢制个构架,又成为三角形桁架,或者钢制斜掾支撑。

一座建筑物的钢构架设计是从屋顶向下进行的。

所有的荷载,不管是恒荷载还是活荷载(包括风荷载),都要按照连续水平面进行计算,直到每一根柱的荷载确定下来,并相应的对基础进行设计。

利用这些信息,结构设计师算出整个结构需要的钢构件的规格、形状,以及连接细节。

对于屋顶桁架和格构梁,设计师利用“三角剖分”的方法,因为三角形是唯一的固有刚度的结构。

因此,格构框架几乎都是有一系列三角形组成。

钢结构可以分成三大类:一是框架结构。

其构件包括抗拉构件、梁构件、柱构件,以及压弯构件;二是壳体结构。

其中主要是轴向应力;三是悬挂结构。

其中轴向拉应力是最主要的受力体系。

网架结构这是刚结构最典型的一种。

多层建筑通常包括梁和柱,一般是刚性连接或是简单的通过沿着提供稳定性的斜向支撑方向在端部连接。

尽管多层建筑是三维的,但通常某个方向即某一维度要比其他维度刚度更大,所以,其有理由被当做是一系列的平面框架。

然而,如果一个框架中某一平面上的构建的特性可以影响其他平面的特性,这个框架就必须当做一个三维框架来考虑。

网壳结构在这类结构中,壳体除了参与传递荷载外,还有其他实用功能。

许多壳体结构中,框架结构也会与壳体一起组合使用。

再强和平屋顶上“外壳”构件也和框架结构一起承担压力。

悬挂结构在悬挂结构中,张拉索是主要的受力构件。

屋面也可以有索支撑。

这种形式的结构主要是吊桥。

这种结构的子系统,是有框架结构组成,就像加劲桁架支撑索桥。

由于这种张拉构建能够最有效的承担荷载,结构中的这种设计理念被越来越广泛的应用。

很多不寻常的结构,是由框架、壳体以及悬挂结构的不同组合形式建造。

在美国,钢结构的设计主要依据是美国钢结构协会颁布的规范。

这些规范是很多学者和一线工程师的经验所得。

这些研究成果被综合处理成一套既安全又经济的设计理念的设计程序。

设计过程中数字计算机的出现促使更加精妙可行的设计规则产生。

规范包括一系列保证安全性的规则,尽管如此,设计者必须理解规则的适用性,否则,很可能导致荒谬的、非常不经济的、有时甚至是不安全的设计结果。

建筑规则有时等同于规范。

这些规则涉及所有有关安全性的方面,例如结构设计、建筑细节、防火、暖气和空调、管路系统、卫生系统以及照明系统。

结构和结构构件必须具有足够的强度、刚度、韧性,以在结构的使用中充分发挥其功能。

设计必须提供足够的强度储备,以承当使用期间的荷载,也就是说,建筑物不需承担可能的超负荷。

改变某一结构原来的使用用途,或者由于在结构分析中采用了过度简化的方法而低估了荷载作用,以及施工程序的变更会造成结构的超载。

即使在允许范围内,构建尺寸的偏差也可导致某个构件低于他所计算的强度。

不管采用哪些设计原理,结构设计必须提供足够的安全性。

必需预防超负荷和强度的不足情况。

在过去的三十年里,如何保证设计安全性的研究一直在继续。

使用各种不同的概率方法来研究构件、连接件或者系统的失效可能性。

此外,由于结构钢构件相当高的造价,与人工安装费用相比,材料采购成本是巨大的。

与其他总承包合同中所涉及的混凝土工程、砌筑工程以及土木工程不同,与人工安装费用相比,钢构件的材料成本是相当大的。

随着钢结构建筑的发展,钢结构住宅建筑技术也必将不断的成熟,大量的适合钢结构住宅的新材料也将不断的涌现,同时,钢结构行业建筑规范、建筑的标准也将随之逐渐完善。

相信不久的将来,钢结构住宅必然会给住宅产业和建筑行业带来一声深层次的革命,钢结构的应用前景广阔!英文翻译:Steel StructureSteel in one form or another is now probably the most widely used material in the world for building construction. For the framings it has almost entirely replaced timber, except for rather special work, and it has superseded its immediate predecessors, cast iron and wrought iron, for bridges and structural frameworks in general.Steel , the most important construction material of modern times, was introduced in the nineteenth century. Steel, basically an alloy of iron and a small amount of carbon, had been mad up to that time by a laborious process that restricted it to such special uses as sword blades. After the invention of the Bessemer process in 1856, steel was available in large quantities at low prices. The enormous advantage of steel is its tensile strength; that is, it dose not lose its strength when it is under a calculated degree of tension, a force which, as we have seen, tends to pull apart many materials. New alloys have further increased the strength of steel and eliminated some of its problems, such as fatigue.Steel has great advantages for buildings. The steel normally used for structures is known as mild steel; compared with cast iron it is resilient and, up to a point known as the “elastic limit” it will recover its initial shape when the load on it is removed. Even if its loading is increased by considerable margin beyond the elastic limit, it will bend and will stay bent without breaking; whereas cast iron, though strong, is notoriously brittle and, if overloaded, will break suddenly without warning. Steel is also equally strong in both tension (stretching) and compression, which gives it an advantage over the earlier structural metals and over other building materials such as brickwork, masonry, concrete, or timber, which are strong in compression but weak in tension. It is for this reason that steel rods are used in reinforcedconcrete—the concrete resisting all compressive stresses while the steel rods take up all the tensile (stretching) forces.In steel-framed building, the horizontal girders which carry the floors and walls are themselves supported on vertical steel posts,Known as “stanchions” , which transfer the whole load of a building down to the foundations, except for the lowest floor which rests on the ground itself. A flat roof is framed in the same way as a floor. A sloping roof is carried on open steel lattice frames called roof trusses or on steel sloping rafters.The steel framework of a building is designed from the roof downwards, all the loading, both “dead” and “live” (including wind forces) , being calculated at successive levels until the total weight carried by each stanchion is determined and the foundations designed accordingly. Whih this information the structural designer calculated the sizes and shapes of the steel parts needed in the whole structure, as wall as details of all the connexions. For roof trusses and lattice girders, he uses the method of “triangulation” because a triangle is the only open frame which is inherently rigid. Therefore, lattice frameworks are nearly always built up from a series of triangles.Steel structures may be divided into three general categories: (a) framed structures, where elements may consist of tension member, columns, beams, and members under combined bending and axial load; (b) shell-type structures, where axial stresses predominate; and (c) suspension-type structures, where axial tension predominates the principal support system.Framed Structures Most typical building construction is in this category. The multistory building usually consists of beams and columns, either rigidly connected or having simple end connections along with diagonal bracing to provide stability. Even though a multistory building is three-dimensional, it usually is designed to be much stiffer in one direction than the other; thus it may reasonably be treated as a series of plane frames. However, if the framing is such that behavior of the members in one plane substantially influences the behavior in another plane, the frame must be treated as a three-dimensionalspace frame.Shell-Type Structures In this type of structure the shell serves a use function in addition to participation in carrying loads. On many shell-type structure, a framed structure may be used in conjunction with the shell. On walls and flat roofs the “skin” elements may be in compression while they act together with a framework.Suspension-Type Structure In the suspension-type structure tension cables are major supporting elements. A roof may be cable-supported. Probably the most common structure of this type is the suspension bridge. Usually a suspension bridge. Since the tension element is the most efficient way of carrying load, structures utilizing this concept are increasingly being used.Many unusual structure utilizing various combinations of framed, shell-type, and suspension-type structure have been built.Structural steel design of buildings in the USA is principally is principally based on the specifications of the American Institute of Steel Construction (AISC), The AISC Specifications are the result of the combined judgment of researchers and practicing engineers. The research efforts have been synthesized into practical design procedures to provide a safe, economical structure. The advent of the digital computer in design practice has made feasible more elaborate design rules.A lot of unusual structure, is made up of frame, shell and different combination forms of hanging structure.In the United States, the design of steel structure is mainly on the basis of regulations promulgated by the American association of steel structure. These specifications are a lot of scholars and a line engineer experience. The results of this study was comprehensive processing into a set of safe and economic design idea of design program. The design process of the digital computer prompted a more sophisticated feasible design rules.Specification includes a series of security rules, in spite of this, the designer must understand the applicability of the rules, otherwise, is likely to lead to absurd, veryuneconomical, sometimes even unsafe design result.Building rules sometimes equated with specification. These regulations cover all aspects relating to the safety, such as structure design, architectural details, fire protection, heating and air-conditioning, piping system, health systems, and lighting systems.Structure and structural components must have sufficient strength, stiffness, toughness, in order to give full play to its functions in the use of the structure. Reserves of design must provide sufficient strength to bear the load during use, that is to say, the buildings do not need to bear the possible overload. Change a structure of the original purpose, or because of excessive simplified method was adopted in the structural analysis and underestimated the load, as well as the construction process of change will cause the overload of the structure. Even within the scope of the permit, building size of the deviation can also lead to a component is lower than the strength he calculates.No matter what design principle, structure design must provide adequate security. The lack of necessary to prevent overload and intensity. Over the past 30 years, the research of how to ensure the safety design has continued. Use a variety of different probability method to study the components, fittings or system failure probability.In addition, due to structural steel components are very high cost, compared with the cost of installation of artificial, material procurement cost is huge. With other involved in the general contract of building project and civil engineering, concrete engineering, compared with the manual installation cost, material cost of steel components are considerable.With the development of steel structure, steel structure residential construction technology will also continue to mature, a lot of new materials will also be suitable for steel structure housing constantly emerging, at the same time, construction specifications, construction steel structure industry standards will be gradually perfected. Believe in the near future, the steel structure housing will inevitably brings to the housing industry and construction industry a profound revolution, the application prospect of steel structure.。

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