工程管理中英文对照外文翻译文献

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土木建筑工程工程管理中英文对照外文翻译文献

土木建筑工程工程管理中英文对照外文翻译文献

(文档含英文原文和中文翻译)中英文资料外文翻译文献外文翻译Abstract:To study the application of continuum structural topology optimization methods to real engineering structures,an optimization method for an optimal topology design of multistory steel frame bracing systems is presented.On a sensitivity analysis,an element removal criterion for continuum structures with stress and multi-displacement constraints under multiple lateral loading conditions is proposed.A concept of mean thickness of a design domain is provided to ensure the reasonableness of optimal results.In the proposed optimization method,the optimal design of an unbraced steel frame without displacement constraints is performed firstly,and then the optimal topology of a bracing system for the multistory steel frame considering displacement constraints is obtained by using evolutionary structural optimization and the given removal criterion,and finally the optima layout of the bracing system is interpreted as bracing members.An example of 3-bay 12-story plane steel frame shows that it is effective for the given optimizationmethod in the optimal design of bracing systems for multistory steel frames.Key words:steel frame;bracing system;continuum;topology optimization;evolutionary structural optimization1.Reinforced ConcretePlain concrete is formed from a hardened mixture of cement ,water ,fine aggregate, coarse aggregate (crushed stone or gravel),air, and often other admixtures. The plastic mix is placed and consolidated in the formwork, then cured to facilitate the acceleration of the chemical hydration reaction lf the cement/water mix, resulting in hardened concrete. The finished product has high compressive strength, and low resistance to tension, such that its tensile strength is approximately one tenth lf its compressive strength. Consequently, tensile and shear reinforcement in the tensile regions of sections has to be provided to compensate for the weak tension regions in the reinforced concrete element.It is this deviation in the composition of a reinforces concrete section from the homogeneity of standard wood or steel sections that requires a modified approach to the basic principles of structural design. The two components of the heterogeneous reinforced concrete section are to be so arranged and proportioned that optimal use is made of the materials involved. This is possible because concrete can easily be given any desired shape by placing and compacting the wet mixture of the constituent ingredients are properly proportioned, the finished product becomes strong, durable, and, in combination with the reinforcing bars, adaptable for use as main members of any structural system.The techniques necessary for placing concrete depend on the type of member to be cast: that is, whether it is a column, a bean, a wall, a slab, a foundation. a mass columns, or an extension of previously placed and hardened concrete. For beams, columns, and walls, the forms should be well oiled after cleaning them, and the reinforcement should be cleared of rust and other harmful materials. In foundations, the earth should be compacted and thoroughly moistened to about 6 in. in depth to avoid absorption of the moisture present in the wet concrete. Concrete should always be placed in horizontal layers which are compacted by means of high frequency power-driven vibrators of either the immersion or external type, as the case requires, unless it is placed by pumping. It must be kept in mind, however, that over vibration can be harmful since it could cause segregation of the aggregate and bleeding of the concrete.Hydration of the cement takes place in the presence of moisture at temperatures above 50°F. It is necessary to maintain such a condition in order that the chemicalhydration reaction can take place. If drying is too rapid, surface cracking takes place. This would result in reduction of concrete strength due to cracking as well as the failure to attain full chemical hydration.It is clear that a large number of parameters have to be dealt with in proportioning a reinforced concrete element, such as geometrical width, depth, area of reinforcement, steel strain, concrete strain, steel stress, and so on. Consequently, trial and adjustment is necessary in the choice of concrete sections, with assumptions based on conditions at site, availability of the constituent materials, particular demands of the owners, architectural and headroom requirements, the applicable codes, and environmental reinforced concrete is often a site-constructed composite, in contrast to the standard mill-fabricated beam and column sections in steel structures.A trial section has to be chosen for each critical location in a structural system. The trial section has to be analyzed to determine if its nominal resisting strength is adequate to carry the applied factored load. Since more than one trial is often necessary to arrive at the required section, the first design input step generates into a series of trial-and-adjustment analyses.The trial-and –adjustment procedures for the choice of a concrete section lead to the convergence of analysis and design. Hence every design is an analysis once a trial section is chosen. The availability of handbooks, charts, and personal computers and programs supports this approach as a more efficient, compact, and speedy instructional method compared with the traditional approach of treating the analysis of reinforced concrete separately from pure design.2. EarthworkBecause earthmoving methods and costs change more quickly than those in any other branch of civil engineering, this is a field where there are real opportunities for the enthusiast. In 1935 most of the methods now in use for carrying and excavating earth with rubber-tyred equipment did not exist. Most earth was moved by narrow rail track, now relatively rare, and the main methods of excavation, with face shovel, backacter, or dragline or grab, though they are still widely used are only a few of the many current methods. To keep his knowledge of earthmoving equipment up to date an engineer must therefore spend tine studying modern machines. Generally the only reliable up-to-date information on excavators, loaders and transport is obtainable from the makers.Earthworks or earthmoving means cutting into ground where its surface is too high ( cuts ), and dumping the earth in other places where the surface is too low ( fills). Toreduce earthwork costs, the volume of the fills should be equal to the volume of the cuts and wherever possible the cuts should be placednear to fills of equal volume so as to reduce transport and double handlingof the fill. This work of earthwork design falls on the engineer who lays out the road since it is the layout of the earthwork more than anything else which decides its cheapness. From the available maps ahd levels, the engineering must try to reach as many decisions as possible in the drawing office by drawing cross sections of the earthwork. On the site when further information becomes available he can make changes in jis sections and layout,but the drawing lffice work will not have been lost. It will have helped him to reach the best solution in the shortest time.The cheapest way of moving earth is to take it directly out of the cut and drop it as fill with the same machine. This is not always possible, but when it canbe done it is ideal, being both quick and cheap. Draglines, bulldozers and face shovels an do this. The largest radius is obtained with the dragline,and the largest tonnage of earth is moved by the bulldozer, though only over short distances.The disadvantages of the dragline are that it must dig below itself, it cannot dig with force into compacted material, it cannot dig on steep slopws, and its dumping and digging are not accurate.Face shovels are between bulldozers and draglines, having a larger radius of action than bulldozers but less than draglines. They are anle to dig into a vertical cliff face in a way which would be dangerous tor a bulldozer operator and impossible for a dragline. Each piece of equipment should be level of their tracks and for deep digs in compact material a backacter is most useful, but its dumping radius is considerably less than that of the same escavator fitted with a face shovel.Rubber-tyred bowl scrapers are indispensable for fairly level digging where the distance of transport is too much tor a dragline or face shovel. They can dig the material deeply ( but only below themselves ) to a fairly flat surface, carry it hundreds of meters if need be, then drop it and level it roughly during the dumping. For hard digging it is often found economical to keep a pusher tractor ( wheeled or tracked ) on the digging site, to push each scraper as it returns to dig. As soon as the scraper is full,the pusher tractor returns to the beginning of the dig to heop to help the nest scraper.Bowl scrapers are often extremely powerful machines;many makers build scrapers of 8 cubic meters struck capacity, which carry 10 m ³heaped. The largest self-propelledscrapers are of 19 m ³ struck capacity ( 25 m ³ heaped )and they are driven by a tractor engine of 430 horse-powers.Dumpers are probably the commonest rubber-tyred transport since they can also conveniently be used for carrying concrete or other building materials. Dumpers have the earth container over the front axle on large rubber-tyred wheels, and the container tips forwards on most types, though in articulated dumpers the direction of tip can be widely varied. The smallest dumpers have a capacity of about 0.5 m ³, and the largest standard types are of about 4.5 m ³. Special types include the self-loading dumper of up to 4 m ³ and the articulated type of about 0.5 m ³. The distinction between dumpers and dump trucks must be remembered .dumpers tip forwards and the driver sits behind the load. Dump trucks are heavy, strengthened tipping lorries, the driver travels in front lf the load and the load is dumped behind him, so they are sometimes called rear-dump trucks.3. Safety of StructuresThe principal scope of specifications is to provide general principles and computational methods in order to verify safety of structures. The “ safety factor ”, which according to modern trends is independent of the nature and combination of the materials used, can usually be defined as the ratio between the conditions. This ratio is also proportional to the inverse of the probability ( risk ) of failure of the structure.Failure has to be considered not only as overall collapse of the structure but also as unserviceability or, according to a more precise. Common definition. As the reaching of a “ limit state ” which causes the construction not to accomplish the task it was designed for. There are two categories of limit state :(1)Ultimate limit sate, which corresponds to the highest value of the load-bearing capacity. Examples include local buckling or global instability of the structure; failure of some sections and subsequent transformation of the structure into a mechanism; failure by fatigue; elastic or plastic deformation or creep that cause a substantial change of the geometry of the structure; and sensitivity of the structure to alternating loads, to fire and to explosions.(2)Service limit states, which are functions of the use and durability of the structure. Examples include excessive deformations and displacements without instability; early or excessive cracks; large vibrations; and corrosion.Computational methods used to verify structures with respect to the different safety conditions can be separated into:(1)Deterministic methods, in which the main parameters are considered as nonrandom parameters.(2)Probabilistic methods, in which the main parameters are considered as random parameters.Alternatively, with respect to the different use of factors of safety, computational methods can be separated into:(1)Allowable stress method, in which the stresses computed under maximum loads are compared with the strength of the material reduced by given safety factors.(2)Limit states method, in which the structure may be proportioned on the basis of its maximum strength. This strength, as determined by rational analysis, shall not be less than that required to support a factored load equal to the sum of the factored live load and dead load ( ultimate state ).The stresses corresponding to working ( service ) conditions with unfactored live and dead loads are compared with prescribed values ( service limit state ) . From the four possible combinations of the first two and second two methods, we can obtain some useful computational methods. Generally, two combinations prevail:(1)deterministic methods, which make use of allowable stresses.(2)Probabilistic methods, which make use of limit states.The main advantage of probabilistic approaches is that, at least in theory, it is possible to scientifically take into account all random factors of safety, which are then combined to define the safety factor. probabilistic approaches depend upon :(1) Random distribution of strength of materials with respect to the conditions of fabrication and erection ( scatter of the values of mechanical properties through out the structure );(2) Uncertainty of the geometry of the cross-section sand of the structure ( faults and imperfections due to fabrication and erection of the structure );(3) Uncertainty of the predicted live loads and dead loads acting on the structure;(4)Uncertainty related to the approximation of the computational method used ( deviation of the actual stresses from computed stresses ).Furthermore, probabilistic theories mean that the allowable risk can be based on several factors, such as :(1) Importance of the construction and gravity of the damage by its failure;(2)Number of human lives which can be threatened by this failure;(3)Possibility and/or likelihood of repairing the structure;(4) Predicted life of the structure.All these factors are related to economic and social considerations such as:(1) Initial cost of the construction;(2) Amortization funds for the duration of the construction;(3) Cost of physical and material damage due to the failure of the construction;(4) Adverse impact on society;(5) Moral and psychological views.The definition of all these parameters, for a given safety factor, allows construction at the optimum cost. However, the difficulty of carrying out a complete probabilistic analysis has to be taken into account. For such an analysis the laws of the distribution of the live load and its induced stresses, of the scatter of mechanical properties of materials, and of the geometry of the cross-sections and the structure have to be known. Furthermore, it is difficult to interpret the interaction between the law of distribution of strength and that of stresses because both depend upon the nature of the material, on the cross-sections and upon the load acting on the structure. These practical difficulties can be overcome in two ways. The first is to apply different safety factors to the material and to the loads, without necessarily adopting the probabilistic criterion. The second is an approximate probabilistic method which introduces some simplifying assumptions ( semi-probabilistic methods ) .2. 中文翻译摘要:为了研究连续型拓扑优化理论在实际工程中的应用,该文给出了一种多层钢框架支撑体系连续型拓扑优化设计方法。

建筑施工质量管理体系外文翻译参考文献

建筑施工质量管理体系外文翻译参考文献

建筑施工质量管理体系外文翻译参考文献1. GB/T -2016 英文名称:Quality management systems--Requirements《质量管理体系要求》2. GB/T -2016 英文名称:Quality management systems--Guidelines for the application of ISO 9001:2015《质量管理体系应用指南》3. GB -2013 英文名称:Code for construction quality acceptance of building engineering《建筑工程质量验收规范》4. GB -2011 英文名称:Code for acceptance of constructional quality of masonry engineering《砌体工程施工质量验收规范》5. GB -2010 英文名称:Code for design of concrete structures《混凝土结构设计规范》6. GB -2013 英文名称:Standard for building drawing standardization《建筑施工图件编制规范》7. GB -2001 英文名称:Code for acceptance of construction quality of pile foundation engineering《桩基工程施工质量验收规范》8. /T 11-2017 英文名称:Technical specification for concrete structure of tall building《高层建筑混凝土结构技术规范》9. 63-2013 英文名称:Technical specification for strengthening of building structures using carbon fiber reinforced plastics 《建筑结构加固碳纤维布增强复合材料技术规范》10. 81-2002 英文名称:Technical specification for application of sprayed mortar in building construction and acceptance of quality 《建筑喷涂砂浆工程施工及质量验收技术规定》。

工程管理专业外文文献以及汉文翻译

工程管理专业外文文献以及汉文翻译

外文文献:The project management office as an organisational innovationBrian Hobbs *, Monique Aubry,Denis ThuillierUniversity of Quebec at Montreal, Department of Management and Technology,PO Box 8888,Downtown Station,Montreal,Que,Canada H3C 3P8Received 15 May 2008; accepted 20 May 2008AbstractThe paper presents an investigation of the creation and the reconfiguration of project management offices (PMOs) as an organizational innovation。

The analysis of 11 organisational transformations centred on the implementation or reconfiguration of PMOs is presented. The objective of the paper is to contribute to a better understanding of PMOs and of the dynamic relationship between project management and the organisational context。

The aim is also to integrate the examination of PMOs as an organisational innovation into the mainstream of research on the place of project management in organisations and more widely to the ‘‘rethinking of project management.”1。

工程管理外文翻译---国际建设工程风险分析

工程管理外文翻译---国际建设工程风险分析

本科生毕业论文外文翻译题目国际建设工程风险分析姓名学号学院管理科学与工程专业工程管理指导教师2012年4月25日Risk Analysis of the International Construction ProjectABSTRACTThis analysis used a case study methodology to analyse the issues surrounding the partial collapse of the roof of a building housing the headquarters of the Standards Association of Zimbabwe (SAZ). In particular, it examined the prior roles played by the team of construction professionals. The analysis revealed that the SAZ‟s traditional construction project was generally characterized by high risk. There was a clear indication of the failure of a contractor and architects in preventing and/or mitigating potential construction problems as alleged by the plaintiff. It was reasonable to conclude that between them the defects should have been detected earlier and rectified in good time before the partial roof failure. It appeared justified for the plaintiff to have brought a negligence claim against both the contractor and the architects. The risk analysis facilitated, through its multi-dimensional approach to a critical examination of a construction problem, the identification of an effective risk management strategy for future construction projects. It further served to emphasize the point that clients are becoming more demanding, more discerning, and less willing to accept risk without recompense. Clients do not want surprise, and are more likely to engage in litigation when things go wrong.KEY WORDS Arbitration claims construction contracts litigation project and riskThe structural design of the reinforced concrete elements was done by consulting engineers Knight Piesold (KP). Quantity surveying services were provided by Hawkins, Leshnick & Bath (HLB). The contract was awarded to Central African Building Corporation (CABCO) who was also responsible for the provision of a specialist roof structure using pat ented “gang nail” roof trusses. The building construction proceeded to completion and was handed over to the owners on Sept. 12, 1991. The SAZ took effective occupation of the headquarters building without a certificate of occupation. Also, the defects liability period was only three months .The roof structure was in place 10 years before partial failure in December 1999. The building insurance coverage did not cover enough, the City of Harare, a government municipality, issued the certificate of occupation 10 years after occupation, and after partial collapse of the roof .At first the SAZ decided to go to arbitration, but this failed to yield an immediate solution. The SAZ then decided to proceed to litigate in court and to bring a negligence claim against CABCO. The preparation for arbitration was reused for litigation. The SAZ‟s quantified losses stood at approximately $ 6 million in Zimbabwe dollars (US $1.2m) .After all parties had examined the facts and evidence before them, it became clear that there was a great probability that the courts might rule that both the architects and the contractor were liable. It was at this stage that the defendants‟ lawyers requested that the matter be settled out of court. The plaintiff agreed to this suggestion, with the terms of the settlement kept confidential .The aim of this critical analysis was to analyse the issues surrounding the partial collapse of the roof of the building housing the HQ of Standard Association of Zimbabwe. It examined the prior roles played by the project management function and construction professionals in preventing/mitigating potential construction problems. It further assessed the extent to which the employer/client and parties to a construction contract are able to recover damages under that contract. The main objective of this critical analysis was to identify an effective risk management strategy for future construction projects. The importance of this study is its multidimensional examination approach.Experience suggests that participants in a project are well able to identify risks based on their own experience. The adoption of a risk management approach, based solely in past experience and dependant on judgement, may work reasonably well in a stable low risk environment. It is unlikely to be effective where there is a change. This is because change requires the extrapolation of past experience, which could be misleading. All construction projects are prototypes to some extent and imply change. Change in the construction industry itself suggests that past experience is unlikely tobe sufficient on its own. A structured approach is required. Such a structure can not and must not replace the experience and expertise of the participant. Rather, it brings additional benefits that assist to clarify objectives, identify the nature of the uncertainties, introduces effective communication systems, improves decision-making, introduces effective risk control measures, protects the project objectives and provides knowledge of the risk history .Construction professionals need to know how to balance the contingencies of risk with their specific contractual, financial, operational and organizational requirements. Many construction professionals look at risks in dividually with a myopic lens and do not realize the potential impact that other associated risks may have on their business operations. Using a holistic risk management approach will enable a firm to identify all of the organization‟s business risks. This will increase the probability of risk mitigation, with the ultimate goal of total risk elimination .Recommended key construction and risk management strategies for future construction projects have been considered and their explanation follows. J.W. Hinchey stated that there is and can be no …best practice‟ standard for risk allocation on a high-profile project or for that matter, any project. He said, instead, successful risk management is a mind-set and a process. According to Hinchey, the ideal mind-set is for the parties and their representatives to, first, be intentional about identifying project risks and then to proceed to develop a systematic and comprehensive process for avoiding, mitigating, managing and finally allocating, by contract, those risks in optimum ways for the particular project. This process is said to necessarily begin as a science and ends as an art .According to D. Atkinson, whether contractor, consultant or promoter, the right team needs to be assembled with the relevant multi-disciplinary experience of that particular type of project and its location. This is said to be necessary not only to allow alternative responses to be explored. But also to ensure that the right questions are asked and the major risks identified. Heads of sources of risk are said to be a convenient way of providing a structure for identifying risks to completion of a participant‟s part of the project. Effective risk management is said to require amulti-disciplinary approach. Inevitably risk management requires examination of engineering, legal and insurance related solutions .It is stated that the use of analytical techniques based on a statistical approach could be of enormous use in decision making . Many of these techniques are said to be relevant to estimation of the consequences of risk events, and not how allocation of risk is to be achieved. In addition, at the present stage of the development of risk management, Atkinson states that it must be recognized that major decisions will be made that can not be based solely on mathematical analysis. The complexity of construction projects means that the project definition in terms of both physical form and organizational structure will be based on consideration of only a relatively small number of risks . This is said to then allow a general structured approach that can be applied to any construction project to increase the awareness of participants .The new, simplified Construction Design and Management Regulations (CDM Regulations) which came in to force in the UK in April 2007, revised and brought together the existing CDM 1994 and the Construction Health Safety and Welfare (CHSW) Regulations 1996, into a single regulatory package.The new CDM regulations offer an opportunity for a step change in health and safety performance and are used to reemphasize the health, safety and broader business benefits of a well-managed and co-ordinated approach to the management of health and safety in construction. I believe that the development of these skills is imperative to provide the client with the most effective services available, delivering the best value project possible.Construction Management at Risk (CM at Risk), similar to established private sector methods of construction contracting, is gaining popularity in the public sector. It is a process that allows a client to select a construction manager (CM) based on qualifications; make the CM a member of a collaborative project team; centralize responsibility for construction under a single contract; obtain a bonded guaranteed maximum price; produce a more manageable, predictable project; save time and money; and reduce risk for the client, the architect and the CM.CM at Risk, a more professional approach to construction, is taking its place along with design-build,bridging and the more traditional process of design-bid-build as an established method of project delivery.The AE can review the CM‟s approach to the work, making helpful recommendations. The CM is allowed to take bids or proposals from subcontractors during completion of contract documents, prior to the guaranteed maximum price (GMP), which reduces the CM‟s risk and provides useful input to design. The procedure is more methodical, manageable, predictable and less risky for all.The procurement of construction is also more business-like. Each trade contractor has a fair shot at being the low bidder without fear of bid shopping. Each must deliver the best to get the projec. Competition in the community is more equitable: all subcontractors have a fair shot at the work .A contingency within the GMP covers unexpected but justifiable costs, and a contingency above the GMP allows for client changes. As long as the subcontractors are within the GMP they are reimbursed to the CM, so the CM represents the client in negotiating inevitable changes with subcontractors.There can be similar problems where each party in a project is separately insured. For this reason a move towards project insurance is recommended. The traditional approach reinforces adversarial attitudes, and even provides incentives for people to overlook or conceal risks in an attempt to avoid or transfer responsibility.A contingency within the GMP covers unexpected but justifiable costs, and a contingency above the GMP allows for client changes. As long as the subcontractors are within the GMP they are reimbursed to the CM, so the CM represents the client in negotiating inevitable changes with subcontractors.There can be similar problems where each party in a project is separately insured. For this reason a move towards project insurance is recommended. The traditional approach reinforces adversarial attitudes, and even provides incentives for people to overlook or conceal risks in an attempt to avoid or transfer responsibility.It was reasonable to assume that between them the defects should have been detected earlier and rectified in good time before the partial roof failure. It did appearjustified for the plaintiff to have brought a negligence claim against both the contractor and the architects.In many projects clients do not understand the importance of their role in facilitating cooperation and coordination; the design is prepared without discussion between designers, manufacturers, suppliers and contractors. This means that the designer can not take advantage of suppliers‟or contractors‟ knowledge of build ability or maintenance requirements and the impact these have on sustainability, the total cost of ownership or health and safety .This risk analysis was able to facilitate, through its multi-dimensional approach to a critical examination of a construction problem, the identification of an effective risk management strategy for future construction projects. This work also served to emphasize the point that clients are becoming more demanding, more discerning, and less willing to accept risk without recompense. They do not want surprises, and are more likely to engage in litigation when things go wrong.国际建设工程风险分析摘要此次分析用实例研究方法分析津巴布韦标准协会总部(SAZ)的屋顶部分坍塌的问题。

工程管理方法英文作文

工程管理方法英文作文

工程管理方法英文作文英文:Project management is an essential part of any successful project. There are various methods andtechniques that can be used to manage a project effectively. In my experience, I have found that the Agile methodology and the Waterfall methodology are two of the most popular and effective methods.The Agile methodology is a flexible and adaptive approach to project management. It involves breaking a project down into smaller, more manageable tasks, and then prioritizing them based on their importance. The team works in short iterations, typically two to four weeks, and atthe end of each iteration, they deliver a working productor feature. This approach allows for more frequent feedback and collaboration between the team and stakeholders, which helps to ensure that the project stays on track and meets the needs of the stakeholders.The Waterfall methodology, on the other hand, is a more structured and sequential approach to project management.It involves breaking a project down into distinct phases, such as planning, design, development, testing, and deployment. Each phase must be completed before the next one can begin, and there is little room for changes or adjustments once a phase has been completed. This approach is best suited for projects with well-defined requirements and a clear scope.In my experience, I have found that the Agile methodology is best suited for projects that are complex and require a high degree of flexibility and collaboration. For example, when I was working on a software development project, we used the Agile methodology to manage the project. We were able to deliver a working product every two weeks, which allowed us to get frequent feedback from the stakeholders and make adjustments as needed. This approach helped us to stay on track and deliver a successful product.On the other hand, I have also used the Waterfall methodology for projects that have well-defined requirements and a clear scope. For example, when I was working on a construction project, we used the Waterfall methodology to manage the project. We were able to break the project down into distinct phases, such as planning, design, construction, and final inspection. This approach helped us to stay organized and ensure that each phase was completed before moving on to the next one.中文:工程管理是任何成功项目的重要组成部分。

工程管理专业毕业设计外文翻译---研究建筑施工企业的项目成本控制

工程管理专业毕业设计外文翻译---研究建筑施工企业的项目成本控制

Study on Project Cost Control of Construction EnterprisesBy: R. Max WidemanAbstract With the increasing maturity of construction market, the competition between construction enterprises is becoming fierce. The project profit is gradually decreasing. It demands that all construction enterprises enhance their cost control, lower costs, improve management efficiency and gain maximal profits. This paper analyses the existing problems on project cost control of Chinese construction enterprises, and proposes some suggestions to improve project cost control system.Key Words :Construction enterprises, Project management, Cost controlAfter joining the WTO, with Chinese construction market becoming integrated, the competition among architectural enterprises is turning more intense. Construction enterprises must continually enhance the overall competitiveness if they want to develop further at home and abroad construction market. Construction Enterprises basically adopt the "project management-centered" model, therefore, it is particularly important to strengthen project cost control.1.The Current Domestic Project Cost Classification and Control MethodsCost refers to the consumption from producing and selling of certain products, with the performance of various monetary standing for materialized labor and labor-consuming. Direct and indirect costs constitute the total cost, also known as production cost or manufacturing cost. Enterprise product cost is the comprehensive indicator to measure enterprise quality of all aspects. It is not only the fund compensation scale, but also the basis to examine the implementation of cost plan. Besides, it can provide reference for product pricing According to the above-mentioned definition and current domestic cost classification, construction project cost can be divided into direct costs and indirect costs. Direct costs include material cost, personnel cost, construction machinery cost, material transportation cost, temporarily facility cost, engineering cost and other direct cost. Indirect costs mainly result from project management and company's cost-sharing, covering project operating costs (covering the commission of foreign projects), project's management costs (including exchange losses of foreign projects)and company's cost-sharing.At present the main method for domestic construction enterprises to control project cost is to analyze cost, naming economic accounting, which is the major components of cost management and the analysis of economic activities. In accordance with its scope of target and deep-level of content, GM project cost analysis method can be divided into two categories, namely, comprehensive analysis of project cost and cost analysis of unit project Comprehensive analysis of project cost. It is carried in terms of budget and final accounts, cost reduction programs and construction installation costs. The methods used are as follows: (1) comparing the estimated cost and actual cost. Check the result to reduce cost, lower cost index and budget status. (2) comparing actual cost and project cost. Check cost reduction programs as well as the windage between the actual cost and plan cost. Inspect the rationality and implementation of techniques organizational measures and management plans.(3) comparing lower cost of the same period last year. Aanalyze causes and propose the improving direction. (4) Comparison between engineering units in cost-cutting. Identify the units cost-reducing, which finishes projects, with a view to further cost analysis.Cost analysis of unit project. Comprehensive analysis only understand project cost overruns or lower. If we want to get more detailed information, each cost item analysis of unit project is needed. Analysis mainly from the following aspects:(1) Materials cost analysis. From the view of material stock, production, transportation, inventory and management, we can analyze the discrepancy impact of material price and quantity, the cost-reducing effectiveness resulting from various technical measures, the loss from poor management.(2) Labor cost analysis . From the number of employment, hours of use, ergonomics, as well as wage situation, we can identify the savings and waste during labor use and fixed management.(3) Construction machinery cost analysis. From the construction options, mechanization degree, mechanical efficiency, fuel consumption, mechanical maintenance, good rates and utilization, we can analyze the yield and cost discrepancy of fixed-class ergonomics, the cost of poor classes, focused on improving mechanical utilization efficiency and waste caused by poor management.(4) Management cost analysis. From construction task and organizational staffing changes,non-production personnel changes, as well as other expenditure savings and waste, we can analyze management fees and justify the rationality of expenditure.(5) Technology organization measures implementing analysis. It can increase experience for future establishment and implementation of technical organization projects.(6) Other direct costs analysis. Focus on the analysis of second removal and water, electricity, wind, gas and other expenses situation during construction.2. The shortcomings of cost-control methodsAt present, domestic construction projects cost-control methods have played a significant role for Chinese construction industry and construction enterprises to reduce cost and gain sustainable development. However, we should be aware that these methods exist some shortcomings as follows:2.1 Lack of systemization.Presently, the cost control of construction enterprises is a simple control on cost. In fact, project cost control is closely related with project plans and progress, quality and safety. Therefore, cost control should include above-mentioned elements.2.2 Lack of real timeModern project management is increasingly tending real-time management and forward-looking management, paying more attention to "promptly identify and solve problems", emphasizing as much as possible to identify and solve problems before problems occur. The current control system is to control after problems occur, which can't avoid loss.In addition, current cost-control method is static. It can't monitor and reflect timely costs change, therefore, this method can't provide the support of decision-making for projects management under construction.2.3 Lack of error-checking and error-correcting mechanismThe current cost-control method is the single-class without error-checking and error-correcting mechanism. If mistakes occur in the future, we can't discover timely, or even impossible found. 2.4 Lack of compatibilityThere is lack of compatibility between project cost-control and project finance and corporate management system. The project budget is built on ration, but project financial item subjects are based on current financial general regulation. This is not consistent betweenmethods. Specific to the software, financial sector of domestic construction enterprises is generally adopting some general financial software, such as UF, IBM. The software is not specifically for the development of construction enterprise, not reflecting the special nature of construction enterprises. However, the budget software is also not considered financial aspect. The lack of compatibility leads to void labor and low management efficiency. At the same time, it increases the probability of error information and error decision2.5 Limitation on notions and quality of personnelThese days, most of construction enterprises are faced with the shortage of qualified personnel during improving cost-control system. It is difficult to find a suitable person with budget and financial knowledge and practical experience in project management.3. Suggestions for improving domestic cost-control methodsFrom the view of enterprises and projects, project cost control is a system engineering. It needs standardization and systematization, closely related to many factors. If current domestic construction enterprises want to establish a practical and efficient cost control systems, the cost-control methods must be improved as follows:3.1 Establish systemic cost-control systemAccording to the specific situation of enterprises, company's cost-control guiding documents should be developed. Based on current fixed budget, enterprises develop work breakdown structure of specific conditions. And on these base, along with progress, quality and safety factors, cost control system will be established ultimately, including the establishment of project cost real-time control (the first class by full-time staff in the execution of project cost control, reporting cycle for one week or fortnight), project cost integrated control (the second class, by financial officers in the execution of projects, reporting cycle for fortnight or a month) and corporate cost control (the third class, by company's financial sector, reporting cycle for a month or a quarter). Such three class cost control system resolve the problems of real-time and error-correcting mechanism.3.2 Develop specific control processesAccording to enterprises' specific circumstances, we should formulate specific control processes, identify levels for controlling reporting periods, and arrange specific persons to monitor. Throughout reporting period, two kinds of data or information need to be collected: (1)the actual execution of data, including the actual time for beginning or end, and the actual cost.(2) the project scope, progress plan and budget change information. These changes may result from the clients or project teams, or from some unforeseen things such as natural disasters, labor strikes or key project team members to resign. These changes should be included in project plan and obtained the consent of customers, then new baseline plan need to establish. The scope, progress and budget of new plan may be different from initial plan.Above-discussed data or information must be timely collected, so that it can become the base to update project progress and budget. For example, if the project reporting period is a month, data and information should be collected at the end of month as far as possible, which can guarantee progress in the updated plan and budget.3.3 Improve project financial subjectBased on work breakdown structure, enpterpries should improve project financial subjects so that projects match with real-time cost control, company's financial and cost control systems, which can solve the compatibility between cost control and finance. At the same time, financial system and cost control system using the same data format, similar forms and data-sharing can improve effectively. In the short term, construction enterprise can transform the existing software and statements to achieve cost savings and reduce the impact of system transformation. In the long-term, enterprises can adopt suitable management software and build company's integrated management system.3.4 Balance precision control and cost controlWhen improving project control system, we should pay attention to balance precision control and cost control. Cost control is through the whole process of project. Under normal circumstances, enterprises can take a fixed period report. If new problems will be detected, then enterprises should increase the reporting frequency until problems are resolved.3.5 Train current staffEnterprises should gradually train the existing staff for the future reserves. In any system, human element is always the first one. No matter how perfect and advanced a management system is, and it ultimately relies on people.3.6 Identify core contentsThe core contents for cost control are team spirit, technology and work process consistency,standard management methods, foreseeing difficulties and contradictions, fostering a challenging work environment and continuing improvement.研究建筑施工企业的项目成本控制马克斯.怀德曼摘要:随着建筑市场的日趋成熟,建筑施工企业之间的竞争变得激烈。

工程管理毕业设计外文翻译--建筑施工混凝土裂缝的预防与处理

工程管理毕业设计外文翻译--建筑施工混凝土裂缝的预防与处理

毕业设计外文翻译课题名称中兴•文华园7#楼施工组织设计姓名学号院、系、部建筑工程系专业班级工程管理专业指导教师2013年5月Building construction concrete crack ofprevention and processingDimosi M《CANADIAN JOURNAL OF CIVIL ENGINEERING》Abstract:The 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 familiar crack 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 with oneself, control etc. a series problem, harden model of in the concrete existence numerous tiny hole, spirit cave and tiny 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 kind of harmless crack and accept concrete heavy, defend permeation and a little bit other use function not a creation to endanger. But after the concrete be subjected to lotus carry, difference in temperature etc. function, tiny crack would continuously of 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. Concrete building and Gou piece usually all take sewer to make of, because of crack of existence and development usually make inner part of reinforcing bar etc. material creation decay, lower reinforced concrete material of loading ability, durable and anti- permeation 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 engineering is because of the unsteady development of the crack with the result that. Modern age science research with a great deal of the concrete engineering practice certificate, in the concrete engineering crack problem is ineluctable, also acceptable in certainly of the scope just need to adopt valid of measure will it endanger degree control at certain of scope inside. The reinforced concrete norm is also explicit provision: Some structure at place of dissimilarity under the condition allow existence certain the crack of width. But at under construction should as far as possible adopt a valid measure control crack creation, make the structure don't appear crack possibly or as far as possible decrease crack of amount and width, particularly want 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 temperature variety, constringency, inflation, the asymmetry sink to sink etc. reason cause of crack; Have outside carry the crack that the functioncause; Protected environment not appropriate the crack etc. caused with chemical effect. Want differentiation to treat in the actual engineering, work out a problem according to the actual circumstance.In the concrete engineering the familiar crack and the prevention1.Desiccation fissure and preventionDesiccation fissure crack much appear after the concrete protect be over of a period of time or concrete sprinkle to build to complete behind of around a week. In the cement syrup humidity of evaporate would creation desiccation, and this kind of constringency is can't negative. Desiccation fissure crack of the creation 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 loss lead quick, transform bigger, inner part degree of humidity variety smaller transform smaller, bigger surface stem the shrink transform to be subjected to concrete inner part control, creation more big pull should dint but creation crack. The relative humidity is more low, cement syrup body stem shrink more big, stem the shrink crack be more easy creation. Desiccation fissure 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 follow it more in thinner beam plank short to distribute. Desiccation fissur usually the anti-extend of influence concrete, cause the durable of the rust eclipse influence concrete of reinforcing bar, under the function of the water pressure dint would creation the water power split crack influence concrete of loading dint etc. Concrete stem the shrink be main with water ash of the concrete ratio, the dosage of the composition, cement of cement, gather to anticipate of the dosage of the property 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 shrink be subjected to water ash ratio of influence more big, water ash ratio more big, stem shrink more big, so in the concrete match the ratio the design should as far as possible control good water 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 match ratio design give settle of use water quantity. Four is the earlier period which strengthen concrete to protect, and appropriate extension protect of concrete time. Winter construction want tobe appropriate extension concrete heat preservation to overlay time, and to protect. Five is a constitution the accommodation is in the concrete 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 dry heat or strong wind the weather appear, crack's much presenting in the center breadth, both ends be in the center thin and the length be different, with each other not coherent appearance. Shorter crack general long 20-30 cm, the longer crack can reach to a 2-3 m, breadth 1-5 mm. It creation of main reason is: The concrete is eventually almost having no strength or strength before the coagulate very small, perhaps concrete just eventually coagulate but strength very hour, be subjected to heat or compare strong wind dint of influence, the concrete surface lose water to lead quick, result in the capillary creation bigger negative press but make a concrete physical volume sharply constringency, but at this time the strength of concrete again can't resist its constringency, therefore creation cracked. The influence concrete Su constringency open the main factor of crack to have water ash ratio, concrete of condense time, environment temperature, wind velocity, relative humidity etc..Main prevention measure: One is choose to use stem the shrink value smaller higher Portland cement of the earlier period strength or common the Portland cement brine mire. Two is strict the control water ash ratio, the Chan add to efficiently reduce water to increment the collapse of concrete fall a degree and with easy, decrease cement and water of dosage. Three is to sprinkle 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 coagulate surface is moist, perhaps spray to protect etc. to carry on protect in the concrete surface. Five is in the heat and strong wind the weather to want to establish to hide sun and block breeze facilities, protect in time.3. Sink to sink crack and preventionThe creation which sink to sink crack is because of the structure foundation soil quality not and evenly, loose soft or return to fill soil dishonest or soak in water but result in the asymmetry sink to decline with the result that; Perhaps because of template just degree shortage, the template propped up to once be apart from big or prop up bottom loose move etc. to cause, especially at winter, the template prop up at jelly soil up, jelly the soil turn jelly empress creation asymmetry to sink to decline and causeconcrete structure creation crack. This kind crack many is deep enter or pierce through sex crack, it alignment have something to do with sinking to sink a circumstance, general follow with ground perpendicular or present 30 °s-45 °Cape direction development, bigger sink to sink crack, usually have certain of wrong, crack width usually with sink to decline quantity direct proportion relation. Crack width under the influence of temperature variety smaller. The foundation after transform stability sink to sink crack also basic tend in stability.Main prevention measure: One is rightness loose soft soil, return to fill soil foundation a construction at the upper part structure front should carry on necessity of Hang solid with reinforce. Two is the strength that assurance template is enough and just degree, and prop up firm, and make the foundation be subjected to dint even. Three is keep concrete from sprinkle infusing the foundation in the process is soak by water. Four is time that template tore down to can't be too early, and want to notice to dismantle a mold order of sequence. Five is at jelly soil top take to establish template to notice to adopt certain of prevention measure.4. Temperature crack and preventionTemperature crack much the occurrence is in big surface or difference in temperature variety of the physical volume concrete compare the earth area of the concrete structure. Concrete after sprinkling to build, in the hardening the process, cement water turn a creation a great deal of water turn hot, .(be the cement dosage is in the 350-550 kg/m 3, each sign square the rice concrete will release a calories of 17500-27500 kJ and make concrete internal thus the temperature rise to reach to 70 ℃or so even higher)Because the physical volume of concrete be more big, a great deal of water turn hot accumulate at the concrete inner part but not easy send forth, cause inner part the temperature hock, but the concrete surface spread hot more quick, so formation inside outside of bigger difference in temperature, the bigger difference in temperature result in inner part and exterior hot the degree of the bulge cold shrink dissimilarity, make concrete surface creation certain of pull should dint. When pull should dint exceed the anti- of concrete pull strength extreme limit, concrete surface meeting creation crack, this kind of crack much occurrence after the concrete under construction period. In the concrete of under construction be difference in temperature variety more big, perhaps is a concrete to be subjected to assault of cold wave etc., will cause concrete surface the temperature sharply descend, but creation constringency, surface constringency of the concrete be subjected to inner part concrete of control, creation very big of pull should dint but creation crack, this kind of crack usually just in more shallow scope of the concretesurface creation.The alignment of the temperature crack usually none settle regulation, big area structure the crack often maneuver interleave; The size bigger structure of the beam plank length, the crack run parallel with short side more; Thorough with pierce through sex of temperature crack general and short side direction parallelism or close parallelism, crack along long side cent the segment appear, in the center more airtight. Crack width the size be different, be subjected to temperature variety influence more obvious, winter compare breadth, summer more narrow. The concrete temperature crack that the heat inflation cause is usually in the center the thick both ends be thin, but cold shrink crack of thick thin variety not too obvious. The emergence of the this kind crack will cause the rust eclipse of reinforcing bar, the carbonization of concrete, the anti- jelly which lower concrete melt, anti- tired and anti-extend ability etc..Main prevention measure: One is as far as possible choose to use low hot or medium hot water mire, like mineral residue cement, powder ash from stove cement etc. Two is a decrease cement dosage, cement dosage as far as possible the control is in the 450 kg/m 3 following. Three is to lower water ash ratio, water ash of the general concrete ratio control below 0.6.Four is improvement the bone anticipate class to go together with, the Chan add powder ash from stove or efficiently reduce water etc. to come to reduce cement dosage and lower water to turn hot. Five is an improvement concrete of mix blend to process a craft, lower sprinkle of concrete to build temperature. Six is the in addition that the Chan add a have of fixed amount to reduce water and increase Su, slow coagulate etc. function in the concrete, improvement the concrete mix to match a thing of mobility, protect water, lower water to turn hot, postpone thermal spike of emergence time. Seven is the heat season sprinkle to build can the adoption take to establish to hide sun plank etc. assistance measure control concrete of temperature rise, lower to sprinkle temperature of build the concrete. Eight is the temperature of big physical volume concrete should the dint relate to structure size, concrete structure size more big, temperature should dint more big, so want reasonable arrangement construction work preface, layering, cent the piece sprinkle to build, for the convenience of in spread hot, let up control. Nine is at great inner part constitution of the physical volume concrete cool off piping, cold water perhaps cold air cool off, let up concrete of inside outside difference in temperature. Ten is the supervision which strengthen concrete temperature, adopt to cool off in time, protection measure.11 is to reserve temperature constringency to sew.12 is to let up to control, sprinkle proper before building concrete in the pitch rock and old concrete top build a 5 mm or so sandmat a layer or usage asphalt etc. material Tu2 Shua.13 is to strengthen concrete to protect, the concrete after sprinkle build use moist straw in time, hemp slice's etc. overlay, and attention sprinkle water to protect, appropriate extension protect time, assurance the concrete surface be slow-moving cool off. At the cold season, concrete surface should constitution heat preservation measure, in order to prevent cold wave assault.14 is the allocation be a little amount in the concrete of reinforcing bar perhaps add fiber material concrete of temperature crack control at certain of scope inside. ConclusionThe crack is widespread in the concrete structure existence of a kind of phenomenon, it of emergence not only will lower the anti-extend of building ability, influence building of usage function, and will cause the rust eclipse of reinforcing bar, the carbonization of concrete, lower the durable 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.建筑施工混凝土裂缝的预防与处理迪默斯M《加拿大土木工程学报》摘要:混凝土的裂缝问题是一个普遍存在而又难于解决的工程实际问题,本文对混凝土工程中常见的一些裂缝问题进行了探讨分析,并针对具体情况提出了一些预防、处理措施。

工程管理外文翻译(原文+译文)

工程管理外文翻译(原文+译文)

Concrete Construction matterT. Pauly, M. J. N. PriestleyAbstractViewed in terms of accepted practices, concrete construction operations leave much to be desired with respect to the quality, serviceability, and safety of completed structures. The shortcomings of these operations became abundantly clear when a magnitude 7.6 earthquake struck northern Paki-stan on October 8, 2005, destroying thousands of buildings, damaging bridges, and killing an esti-mated 79,000 people. The unusually low quality of construction operations prevalent was a major cause of the immense devastation.Keywords: Concrete Placing Curing Construction TechnologyPlacing ConcreteIf concrete is placed in the surface, the sur-face should be filled with water sufficiently to prevent it from absorbing the concrete of its water. If fresh concrete is to be placed on or nearby to concrete that has solidified, the surface of the placed concrete should be cleaned absolutely, preferably with a high-pressure air or water jet or steel-wire brushes. The surface should be wet, but there should be no much water. A little quantity of cement grout should be brushed over the whole area, and then followed immediately with the application of a 1/2-in Layer of mortar. The fresh concrete should be placed on or against the mortar.In order to decrease the disintegration re-sulting from carriage after it is placed. The con-crete should be placed as nearly as probably in itsfinal point. It should be placed in layers to permit uniform compaction. The time interval between the placing of layers should be limited to assure perfect bond between the fresh and previously placed concrete.In placing concrete in deeper patters, a ves-sel should be used to limit the free fall to not over 3 or 4 ft, in order to prevent concrete disintegra-tion. The vessel is a pipe made of lightweight metal, having adjustable lengths and attached to the bottom of a hopper into which the concrete is deposited. As the patters are filled, sections of the pipe may be removed.Immediately after the concrete is placed, it should be compacted by hand pudding or a me-chanical vibrator to eliminate voids. The vibrator should be left in one position only long enough to reduce the concrete around it to a plastic mass; then the vibrator should be moved, or disintegra-tion of the aggregate will occur. In general, the vibrator should not be permitted to penetrate concrete in the prior lift.The mainly advantage of vibrating is that it permits the use of a drier concrete, which has a higher strength because of the reduced water content. Among the advantages of vibrating con-crete are the following:1.The decreased water permits a reduction in the cement and fine aggregate because less cement paste is needed.2.The lower water content decreases shrinkage and voids.3.The drier concrete decreases the cost of finishing the surface.4.Mechanical vibration may replace three to eight hand puddles.5.The lower water content increases the strength of the concrete.6.The drier mixture permits theremoval of some patters more quickly, which may reduce the cost of patters.Curing ConcreteIf concrete is to gain its maximum strength and other desirable properties, it should be cured with adequate moisture and at a favorable tem-perature. Failure to provide these conditions may result in an inferior concrete.The initial moisture in concrete is adequate to hydrate all the cement, provided it is not should replace the moisture that does evaporate. This may be accomplished by many methods, such as leaving the patters in place, keeping the surface wet, or covering the surface with a liquid curing compound, which comes being to a water-tight membrane that prevents the escape of the initial water. Curing compounds may be applied by brushes or pressure sprayers. A gallon will cover 200 to 300 sq ft.Concrete should be placed at a temperature not less than 40 or more than 80°F.A lower tem-perature will decrease the rate of setting, while ahigher temperature will decrease the ultimate strength.Placing Concrete in Cold WeatherWhen the concrete is placed during cold weather, it is usually necessary to preheat the water, the aggregate, or both in order that the ini-tial temperature will assure an initial set and gain in strength .Preheating the water is the most ef-fective method of providing the necessary tem-perature. For this purpose a water reservoir should be equipped with pipe coils through which steam can be passed, or steam may bedischarged directly into the water, several outlets being used to given better distribution of the heat.When the temperatures of the mixtures are known, some specific charts may be used to cal-culate the temperature of concrete. A straight line pass all three scales, passing through every two known temperatures, will assure the determina-tion of the third temperature. If the surface of sand isdry, the fact lines of the scales giving the temperature of concrete should be used. However, if the sand contains about 3 percent moisture, the dotted lines should be used.Specifications usually demand that freshly placed concrete shall be kept at a temperature of not less than 70°F for 3 days or 50°F for 5 days after it is placed. Some proper method must be provided to keep the demanded temperature when the cold weather is estimated.Reinforcing steels for concreteCompared with concrete, steel is a high strength material. The useful strength of ordinary reinforcing steels in tension as well as compres-sion, i.e., the yield strength, is about 15 times the compressive strength of common structural con-crete, and well over 100 times its tensile strength. On the other hand, steel is a high-cost material compared with concrete. It follow that the two materials are the best used in combination if theconcrete is made to resist the compressive stresses and the compressive force, longitudinal steel reinforcing bars are located close to the ten-sion face to resist the tension force., and usually additional steel bars are so disposed that they re-sist the inclined tension stresses that are caused by the shear force in the beams. However, rein-forcement is also used for resisting compressive forces primarily where it is desired to reduce the cross-sectional dimensions of compression members, as in the lower-floor columns of multi-story buildings. Even if no such necessity exits , a minimum amount of reinforce- ment is placed in all compression members to safeguard them against the effects of small accidental bending moments that might crack and even fail an unre-inforced member.For most effective reinforcing action, it is essential that steel and concrete deform together, i. e., that there be a sufficiently strong bond be-tween the two materials to ensure that no relative movements of the steel bars and the surrounding concrete occur. This bond is provided by the rela-tively large chemical adhesion which develops at the steel-concrete interface, by the natural roughness of the mill scale of hot-rolled rein-forcing bars , and by the closely spaced rib-shap-ed surface deformations with which reinforcing bars are furnished in order to provide a high de-gree of interlocking of the two materials.Steel is used in two different ways in con-crete structures: as reinforcing steel and as prestressing steel .reinforcing steel is placed in the forms prior to casting of the concrete. Stresses in the steel, as in the hardened concrete, are caused only by the loads on the structure, except for possible parasitic stresses from shrinkage or similar causes. In contrast, in priestesses concrete structures large tension forces are applied to the reinforcement prior to letting it act jointly with the concrete in resistingexternal.The most common type of reinforcing steel is in the form of round bars, sometimes called rebars, available in a large range of diameters,from 10 to 35 mm for ordinary applications and in two heavy bar sizes off 44 and 57 mm these bars are furnished with surface deformations for the purpose of increasing resistance to slip be-tween steel and concrete minimum requirements for these deformations have been developed in experimental research. Different bar producers use different patterns, all of which satisfy these requirements.Welding of rebars in making splices, or for convenience in fabricating reinforcing cages for placement in the forms, may result in metal-lurgical changes that reduce both strength and ductility, and special restrictions must be placed both strength and ductility, and special restric-tions must be placed both on the type of steel used and the welding procedures the provisions of ASTM A706 relatespecifically to welding.In reinforced concrete a long-time trend is evident toward the use of higher strength materi-als, both steel and concrete.Reinforcing bars with 40ksi yield stress , almost standard 20 years ago , have largely been replaced by bars with 60ksi yield stress , both because they are more economical and because their use tends to reduce congestion of steel in the forms .The ACI Code permits reinforcing steels up to Fy=80ksi. Such high strength steels usually yield gradually but have no yield plateau in this situation the ACI Code requires that at the speci-fied minimum yield strength the total strain shall not exceed 0.0035 this is necessary to make cur-rent design methods, which were developed for sharp-yielding steels with a yield plateau, appli-cable to such higher strength steels. there is no ASTM specification for deformed bars may be used , according to the ACI Code , providing they meet the requirements stated under special circumstances steel in this higher strength range has its place, e.g., in lower-story columns of high-rise buildings.In order to minimize corrosion of rein-forcement and consequent spelling of concrete under sever exposure conditions such as in bridge decks subjected to deicing chemicals , galvanized or epoxy-coated rebars may be specified.Repair of Concrete StructuresReinforced concrete is generally a very du-rable structural material and very little repair work is usually needed. However, its durability can be affected by a variety of causes, including those of design and construction faults, use of inferior materials and exposure to aggressive en-vironment. The need for a repair is primarily dic-tated by the severity of the deterioration as de-termined from the diagnosis. Good workmanship is essential if any thing more than just a cosmetic treatment to the creation is required.1. performance requirements of repair systemHaving established the causes of the defect by carefully diagnosing the distress, the next step should be to consider the requirements of the re-pair method that will offer an effective solution to the problem (see fig.).①DurabilityIt is important to select repair materials that provide adequate durability. Materials used for the repair job should be at least as durable as the substrate concrete to which it is applied.②Protection of steelThe mechanism of protection provided to the reinforcing depends on the type of repair ma-terials used. For example, cementations materials can protect the steel from further corrosion by their inhibitive effect of increasing the alkalinity of the concrete, whereas epoxy resin mortars can give protection against the ingress of oxygen,moisture and other harmful agents.③Bond with substrateThe bond with the substrate must produce an integral repair to prevent entry of moisture and atmospheric gases at the interface. With most re-pair materials, the bond is greatly enhanced with the use of a suitable bonding aid such as an un-filled epoxy resin systems and slurry of Portland cement, plus any latex additives for a Portland cement-based repair system. Precautions should also be takento remove all loose and friable ma-terials from the surfaces to be bonded.④Dimensional StabilityShrinkage of materials during curing should be kept to a minimum. Subsequent dimensional change should be very close in the substrate in order to prevent failure⑤Initial Resistance to Environmentally In-duced DamageSome initial exposure conditions may lead to premature damage lo repairs. For example, partially cured Portland cement repairs can dete-riorate from hot weather preventing full hydration of the cement. To prevent this from happening extra protection during curing time may be nec-essary.⑥Ease of ApplicationMaterials should be easily mixed and ap-plied so that they can be worked readily into small crevices and voids. Ideally, the material should not stick to tools, and should not shear while being trowel led nor slump after placement.⑦AppearanceThe degree to which the repair material should match the existing concrete will depend on the use of the structure and the client' s re-quirements. A surface coating may be required when appearance is important or when cover to reinforcement is small.2. Selection of Repair MethodsA suitable repair counteracts all the defi-ciencies which are relevant to the use of the structure.The selection of tile correct method and material for a particular, application requires careful consideration, whether to meet special requirements for placing strength, durability or other short-or long-term properties. These con-siderations include:1. Nature of the DistressIf alive crack is filled with a rigid material, then either the repair material will eventually fail or some new cracking will occur adjacent to the original crack. Repairs to live cracks must either use flexible materials to accommodate move-ments or else steps must be taken prior to the re-pair to eliminate the movement.2. Position of the CrackTechniques which rely on gravity to intro-duce the material into the crack are more suc-cessfully carried out on horizontal surfaces but are rarely effective on vertical ones.3. EnvironmentIf moisture, water or contaminants are found in the crack, then it is necessary to rectify the leaks Repair to slop leaks may be further com-plicated by the need to make the repairs while the structure is in service and the environment is damp.4. WorkmanshipThe skill the operatives available to carry put the repairs is another relevant factors. Some-times this can mean the difference between a permanent repair and premature failure of the re-pair material.5. CostThe cost of repair materials is usually small compared with the costs of providing access, preparation and actual labor.6. AppearanceThe repair surface may be unsightly, par-ticularly when it appears on a prominent part of the building. In this case, the repair system will include some form of treatment over the entire surface.Reference[1]Philip Jodidio, Contemporary European Architecture, Taschen, Koln, pp.148-153[2]Ann Breen & Dick Rigby, Waterfronts, McGraw-Hill, Inc. New York, 1994, pp.297-300[3]Ann Breen & Dick Rigby, The New Waterfront, Thames and Hudson, London, 1996, pp.118-120[4]Ann Breen & Dick Rigby, The New Waterfront, Thames and Hudson, London, 1996, pp.52-55[5]Robert Holden, International Landscape Design, Laurence King Publishing, London, 1996, pp.10-27[6] A new concept in refrigerant control for heat pumps ,J.R.Harnish,IIR Conference Pa-per,Cleveland,Ohio.May,1996[7]Carrier Corporation-Catalog 523 848,1997[8]Waste Heat Management Handbook, Na-tional Bureau of Standardc Handbook 121, Pub-lica-tion PB 264959, February,1997Ten design principles for air to air heat pumps,Allen Trask,ASHRAE Journal,July,1997重庆科技学院学生毕业设计(论文)外文译文学院建建筑工程学院专业班级工管103学生姓名李学号201044241附件1:外文资料翻译译文混凝土施工事项T.Pauly, M.J.N.Priestley摘要:根据一般承认的惯例看,巴基斯坦的混凝土结构建筑物在结构上的质量,效用和安全需要上都留下了很多值得关注的问题。

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中英文对照外文翻译文献中英文对照外文翻译The Internet is Applicated in Real EstateThe Real Estate Industry and the World Wide Web: Changing Technology, Changing Location.The Internet, in its Web based graphics version, has captured the imagination of both consumers and businesses. Its convenience, speed, low cost and versatility are being exploited on a daily basis in ever-changing ways. Together with its capacity to transform existing businesses, promote new businesses and facilitate exchange of information and data, its other striking attribute has been the speed with which this new technology has spread throughout the global economy.Keywords:The internet;Real Estate;ApplicatedThe number of computer hosts grew by more than ten-fold between 1995 and early 1999. The number of Web sites increased almost 100-fold, to over two million, between 1995 and 1998.By the year 2000, there will be approximately 400-500 million Internet users in the world, and the total number of Web sites will exceed five million.This new technology has the potential for affecting the real estate industry directly and indirectly. Directly, it may become a tool that allows a real estate business to expand its information and sales network. Indirectly, it may change the location equation where and how firms do business which in turn will affect the role of firms involved in real estate development, investment and transactions.Measuring the Spread of the WebThere are few reliable published statistics on Internet or Web use, and statistics reported by different analysts are often inconsistent. Our discussion of the Web and real estate is based on limited information from surveys and on examination of Web sites rather than on more comprehensive data. We have built our overview of the role of the World Wide Web and real estate by examining a variety of sources(including trade publications, existing Web sites, and our own survey of selected real estate firms)From E-mail to E-commerceBefore the advent of the World Wide Web, the Internet existed mostly for the purposes of e-mail, data transfers, newsgroups and bulletin boards, and its reach was limited primarily to the academic and the defense community. The technology itself was not particularly user-friendly, the network speed was not very high, the medium was limited to text and data, and accessing information was cumbersome and time-consuming. The browser technology greatly simplified usage, enabled multimedia information, and created interactive possibilities. The technology brought together TV entertainment, library information, news bulletins, communication and data in one desktop machine.Although initially the greatest patrons of the Internet were the academic community, the commercial sector quickly caught on to the potential of the Web. The private sector saw in the Web an opportunity to widen its marketing reach, lower costs of information dissemination, improve customer relations, and ultimately to conduct sales. Existing private sector Web sites can be roughly categorized into three types, as summarized. The most basic level is for simple information dissemination. The firm registers a Web site and develops a page giving basic company information. The second stage is an expansion of information, marketing goods and services or providing other customer information. The third stage is the addition of transactions tothe activities possible on the Web site.Most business sites at present are in Stage 2. The use of the World Wide Web for detailed information dissemination, and marketing has had several advantages. For the firm, marketing, information dissemination and customer services on the Web can be monitored and analyzed with some details unavailable from conventional methods of marketing using other media. Internet tools can now provide a firm with data on who accessed the site, which pages were visited most, heavily, from where and for how long. This information contributes to improved measures of the results of promotional efforts. The promotional costs associated with the Internet have also been very low. For example, in direct mail marketing, to send a one-page color brochure to 5,000 random addresses will cost upwards of $2,500. The cost of setting up a Web site could be one-tenth of this amount or less (although tracking and analysis can quickly add to the cost)?Many different sectors, including real estate, have found the Internet to be both efficient and cost-effective as a marketing device.The next logical step - a full-fledged office/store on the Web with transaction capability and commerce on the Internet is now being attempted in varying degrees depending on the firm's area of business. Retail sites selling products between $10 and $100, the kind that are traditionally part of a direct mail sales catalog, seem to be the ones having the greatest success(although 4% of sites sell products over $10,000 and another 13% sell products ranging from $100 to$9,999)?A number of retail sites have also harnessed a secondary revenue stream from advertising. Advertising revenues on the Web have crossed the billion-dollar mark and total Internet generated revenue will approach$100 billion this year.Consumers' Use of the WebSurveys of consumers using the Web suggest that a Web site does notsubstitute for the more traditional forms of business, but can greatly facilitate the run-up to the final transaction. The most common use of the Web is for information searching, closely followed by work-related uses, education, and entertainment. A significant majority of those that use the Web for shopping do so to carry out detailed research on product information(90%)and to do price comparisons(85%). This more often leads to purchases through normal channels(67%). Most of the online purchases tend to be of items that are standardized-four of the five top items bought on the Web, according to survey, are software, books, hardware and music (the fifth is travel). More than half of consumers who make purchases on the Web spend less than $500 in a six-month period.The demographics of Web users vary widely in age and income. Surveys by Georgia Tech, Active Media and Web indicate that the average age of Web users is 35 years, with average household income $67,000. Most are college educated (65%). A high proportion of the respondents (42%) has accessed real estate sites.Limits to the Web - Some "Catches" to the New Technology New technology is frequently a mixed blessing, and the World Wide Web is no exception. Apart from the teething troubles that any new technology faces and the time, as well as resources needed to learn, adapt and master it, the Web poses some unique issues and problems of its own. Consumers today are facing information overload of taxing proportions. It is not always easy, or even possible, to locate the relevant information on the Web, despite sophisticated search engines. Once the site is located, fancy graphics, complex linkages, labyrinthine routings, and a lot of irrelevant information may overwhelm the consumer - in short, poor and confusing site design can reduce the site's effectiveness.From the point of view of the business, there are two commonly heardcomplaints. First, the business may find that its site does not figure prominently on search results, limiting the number of customers reached. Second, for many firms, Web initiated leads are as yet few and far between. Real Estate Web SitesReal Estate firms and related businesses were among the early private sector pioneers of Internet use and have had a fast growing presence on the Web. presence on the Web. One example of the real estate sector's presence on the Internet in its pre-World Wide Web incarnation was the real estate classified bulletin board of Prodigy, the online service, which had listings for homes and other real estate. A few real estate related Web sites started in 1994 (generally regarded as the inaugural year of the Web). The New York City Real Estate Guide Web site, created in the summer of 1994, was one of the first to offer free access to the latest New York real estate information. By the summer of 1995, the site was receiving more than 100,000 inquiries a month.The real estate industry registered its entry on the Web in a dramatic way in 1995. By the end of that year there were close to 4,000 real estate Web sites. The content matter of the sites, as well as the mix of real estate related firms on the Web have changed over time. Initially, quite a few of the sites were residential real estate brokerages and listing guides, but fairly rapidly the list expanded to include commercial and retail listings, mortgage brokers,appraisers, architects, real estate attorneys, developers, construction firms, and suppliers. As investment vehicles for real estate expanded, REITs, publicly held firms, and investment advisors also added Web sites.The early real estate broker Web sites quickly took advantage of the unique features of the Web. Prospective customers could find out what properties were for sale or rent, look up detailed descriptions of each listing, view photographs and floor plans, and contact the broker by e-mail. Viewerscould also look up statistical and data reports on conditions in various geographical areas and on emerging macroeconomic trends.Ever since then, the real estate industry has been among the most enthusiastic users of the Web, by some measures accounting for 4% to 6% of commercial Web sites. A survey conducted by Real Estate Broker's Insider in early 1998 confirmed that nearly 95% of the respondents/brokers had a Web site, and more than 90% of the housing stock on sale at a given time is now listed on the Web. Indeed, because of the dispersed, localized nature of the role of information in real estate, the prospective gains from information dissemination, comparability, and Web links were particularly significant in real estate.For much of the real estate sector, the Internet generates not so much the actual transactions themselves, but creates initial leads that are later followed by transactions, purchases and sales. Web sites frequently lead to contacts that are then nurtured through telephone and person-to-person meetings. For residential real estate, Web activity includes residential searches, housing details, and pricing information (both on houses and mortgages), with follow-up contact with brokers. Real estate-related transactions are seen in the hospitality industry (making reservations for hotels and vacation homes and in online mortgage applications). Mortgage and home loan finance companies report both inquiries from mortgage shoppers who obtained initial information from their Web sites, as well as closing of loans through the Web, lead to great savings in time and overhead costs.It is not just the real estate professionals who are enthusiastic about their Internet presence, judging it to be as effective as print and radio advertising. Mortgage shoppers, homebuyers and vacation rental seekers as well applaud, in particular, the convenience it brings to the entire process of searching, researching, comparing, communicating and transacting business.Beyond these sectors, many other types of real-estate related firms are using the Web to broaden their market areas, increase the depth of their marketing, and to provide a range of services to existing customers. Commercial brokers provide not only information on available sites but also on market conditions for different locations and sometimes more in-depth economic analysis of a region. REITs and other investment firms provide detailed information on their products as well as background market or economic information. Public companies provide up-to-date stock quotes and quarterly and annual reports on the Web.Web Penetration and Use: The Experience of Leading Real Estate Firms We conducted a limited survey of a sample of leading real-estate related firms in the US and California. Responses from approximately 60 of these firms showed that over four-fifths had Web Sites by March 1999. 2 Of those with Web sites, one-third had inaugurated their sites by the end of 1996. Among the earliest with a Web presence were brokers, investment firms, lenders, business and financial services firms, law firms, residential developers, and a trade organization. Another third of the group were newcomers, with sites inaugurated in 1998 or early 1999. Commercial developers were prominent among this group, with residential developers, consultants and advisors, lenders, REITs and investment firms also among this group. Those without sites were more likely to be privately held firms with a relatively narrow base of activity (for example, a commercial developer centered in the San Francisco Bay Area)?Most with Web sites used their site to provide information about the company and to market services. In addition, about one-third marketed property from their site, providing detailed information on the characteristics of buildings available, surrounding communities, and other related data. Other Web site uses include employee recruiting, providing information formembers or investors, and disseminating related information on topics such as regulations or real estate markets.What does the Web specifically do for Real Estate?According to Activemedia, an internet research company, some of the sectors experiencing the greatest growth in terms of their presence on the Web in 1998 were computer hardware and software, real estate, publishing and information, finance and Internet services. A significant initial motivation for this rush for the Web is provided by, what can be termed, the "tiptoe" effect. The first ones on the Web had an additional advantage over those who did not; information on their services, products, home listings now be accessed conveniently by those with computers. The low setup cost, however, and the potential disadvantage of not having a Web presence has propelled others in the profession to set up their own sites.Real estate shares in some of the basic advantages of the Web mentioned earlier, such as ease of marketing, communication and feedback from clients, lowered costs of operations and convenience of customer service and support. In addition, the Web provides positive features specific to the real estate industry.Key elements include the following.1.Increased geographic reach.The Web has dramatically increased the geographic reach of both buyers and sellers. Although the "local" aspect of real estate will perhaps never be whittled away completely, there is no doubt that inquiries about properties can now emanate from far away to a much greater degree than before. This, in turn, potentially increases the size and "depth" of the market and makes it more efficient.2.Capability of visualization.In some sense, increased geographic reach has become possible due tothe other emergent feature of the Web, the capability of visualization. In its most state-of-the-art form, Web sites now allow prospective buyers to take virtual tours of homes, resorts, hotels and convention centers.3.Reduced transaction costs.The Web may reduce transactions costs. This has been particularly apparent in the case of mortgages. According to Fannie Mae, 1.5% of all mortgages were handled online this past year. The Web-attributable features that make this kind of a transaction possible are instantaneous comparability, interactive capability, online calculation, online applications, and continuous updating of the sites.4.Improved information dissemination.The Web offers broad opportunities for increasing the scope and depth of information provided by many different types of firms. A well constructed home page gives an overview of a firm's range of services or activities. Links allow the customer or client to learn much more detail about the selected items of most interest, while ignoring less relevant pieces of information. A number of sites take advantage of the ability to link to resources beyond the company's Web pages, linking customers and clients to related Web resources.Unlike retail sectors, such as books and computer hardware, the Web as yet has not become a threat to the "middle man" role of many real estate firms. Instead, it is more likely to be used as a means of expanding services offered or locations served. However, in the long term, the Web and related Internet technology have the potential to change the structure of business activity, which in turn will affect the demand for real estate in type if not in quantity. For example, some retailers already have closed stores while expanding sales on the Web. Also, the Internet has been seen as one factor allowing the decentralization of office space. These trends to date have notled to a decline, but rather to a redistribution in the demand for office, retail and warehouse space.These are summarized .Speculation on Potential Impact of Internet on Real Estate Industry.1.Shortening of Transaction Cycle2.Precise Market Targeting3.Transformed Competition4.Cost savings:a)Marketing,b)Sales,c)Operation5.Possibility of Disintermediation;Lowering of Commissionsbination of Comparison Shopping and Direct Sales7.Access to MBS Secondary MarketHow to Find the Real Estate Sector on the WebThere are a few key sites that can be used to access the broad range of real-estate related Web sites. These include:-Site sponsored by the National Association of Realtors, linking users to realtor, home sales and market information.-Site sponsored by the National Association of Home Builders, providing a wide range of market information.-Directory to commercial real estate sites, including brokers,developers, investors and analysts. and , two sites that provide users with information about mortgage rates, mortgage brokers and with the opportunity to submit an application online. (National Association of Real Estate Investment Trusts) and (Real Estate Investment Advisory Council), two associations related to real estate investment trusts.-The California Association of Realtors site.the site for the Urban Land Institute, with information onthe organization, programs, conferences, and publications related to real estate and land use. has three online magazines including National Real Estate Investor, Shopping Center World, and Midwest Real Estate News. An additional real estate online magazine, can available at .Ashok Deo BardhanRESEARCH FELLOWCynthia A. KrollREGIONAL ECONOMIST互联网在房地产业的应用摘要:互联网,仅仅它的网页图形版本,就已经吸引了众多消费者和商家的目光。

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