工程造价毕业论文外文文献

工程造价毕业设计外文文献及译文外文文献：Construction Standards and CostsUC Irvine new construction pursues performance goals and applies quality standards that affect the costs of capital projects. Periodic re-examination of these goals and standards is warranted.Co nstruction costs are not “high〞or “low〞in the abstract, but rather in relation to specific quality standards and the design solutions, means, and methods used to attain these standards. Thus, evaluating whether construction costs are appropriate involves: • first, determining whether quality standards are excessive, insufficient, or appropriate;• second, determining whether resultant project costs are reasonable pared to projects with essentially the same quality parameters.“Quality〞enpasses the durability of building systems and finishes; the robustness and life-cycle performance of building systems; the aesthetics of materials, their position, and their detailing; and the resource-sustainability and efficiency of the building as an overall system.Overall Goals and Quality StandardsUC Irvine, in order to support distinguished research and academic programs, builds facilities of high quality. As such, UC Irvine’s facilities aim to convey the “look and feel,〞as well as embody the inherent construction quality, of the best facilities of other UC campuses, leading public universities, and other research institutions with whom we pete for faculty, students, sponsored research, and general reputation.Since 1992, new buildings have been designed to achieve these five broad goals:1. New bu ildings must “create a place,〞rather than constitute stand-alone structures, forming social, aesthetic, contextually-sensitive relationships with neighboring buildings and the larger campus.2. New buildings reinforce a consistent design framework of classical contextual architecture, applied in ways that convey a feeling of permanence and quality and interpreted in ways that meet the contemporary and changing needs of a modern research university.3. New buildings employ materials, systems, and design features that will avoid the expense of major maintenance (defined as >1 percent of value)for twenty years.4. New buildings apply “sustainability〞principles -- notably, outperforming Title 24 (California’s energy code) by at least 20 percent.5. Capital construction projects are designed and delivered within theapproved project budget, scope, and schedule.UC Irvine’s goals for sustainable materials and energy performance were adopted partly for environmental reasons, and partly to reverse substantial operating budget deficits. The latter problems included a multi-million dollar utilities deficit that was growingrapidly in the early ‘90s, and millions of dollars of unfunded major maintenance that was emerging prematurely in buildings only 10-20 years old. Without the quality and performance standards adopted in 1992, utilities deficits and unfunded major maintenance costs would have exceeded $20 million during the past decade, and these costs would still be rising out-of-control.UC Irvine’s materials standards, building systems standards, sustainability and energy efficiency criteria, and site improvements all add cost increments that can only be afforded through aggressive cost management. Institutions that cannot manage capital costs tend to build projects that consume excessive energy, that cost a lot to maintain, that suffer premature major maintenance costs, and that require high costs to modify. Such problems tend to pound and spiral downward into increasingly costly consequences.Every administrator with facilities experience understands this dynamic. Without effective construction cost management, quality would suffer and UC Irvine would experience all of these problems.The balance of this document outlines in greater detail the building performance criteria and quality standards generally stated above, organized according to building systems ponent classes. Each section discusses key cost-drivers, cost-control strategies, and important cost trade-offs. Design practices cited are consistently applied (although some fall short of hard and fast “rules〞).Building Organization and MassingConstruction cost management starts with the fundamentals of building organization andmassing. UC Irvine’s new structures’ floor plates tend to have length-to-width ratios<1.5, to avoid triggering disproportionate costs of external cladding, circulation, and horizontal mechanical distribution. Our new buildings tend to be at least three floors high -- taller if floor plate areas do not dip below a cost-effective threshold, and generally taller in the case of non-laboratory buildings (but not so tall that a high-rise cost penalty is incurred). Other design ratios are observed, such as exterior cladding area/floor area <0.5, and roof+foundation area/floor area <0.4.Architectural articulation is generally achieved through textured or enriched materials,integral material detailing (such as concrete reveal patterning), and applied detailing (e.g.,2window frames and sills), particularly at the building base. Large-scale articulation is concentrated at the roofline (e.g., shaped roof forms) and at the pedestrian level (e.g.,arcades), where it will “create the biggest bang for the buck,〞rather than through modulating the building form, itself. This is more than a subtle design philosophy, as the cost impact is substantial.Lab buildings pleted in the past decade separate laboratory and non-laboratory functions into distinct, adjoined structures (although such a building may look like one structure). Consolidated non-laboratory functions include faculty, departmental, staff,post-doc, and graduate student offices; restrooms; circulation (elevators, lobbies, primary stairways); classrooms, seminar rooms, conference rooms, and social areas designed tofoster interaction and to provide a safe area for eating and drinking; dry labs and dry lab support functions; and general administrative support.Consolidating these functions into a separate structure provides considerable cost savings:lower-cost HVAC (heating/ventilation/air-conditioning) system, wider column spacing, lower floor stiffness (less stringent vibration criterion), lower floor-loading,fewer fire-control features and other code requirements, steel-framed or steel/concrete hybrid structural system with concrete flat-slab flooring system, smaller footings, and(typically) curtain wall fenestration. This approach usually enables offices to have operable windows.This two-building approach can be seen clearly at Gillespie Neurosciences Building, the Sprague Building, Hewitt Hall, and the UCI Medical Center Health Sciences Laboratory,where consolidating and separating non-laboratory functions saved 7-10 percent in overall construction costs and 15 percent/year in energy expense. (The non-laboratory building incurs a small fraction of the energy expense of the laboratory block.)A set of design strategies, applied in bination, has proven effective in controlling the cost of laboratories:• Utilizing a consistent lab module• Utilizing a reasonable vibration criterion and locating ultra-sensitive conditions at-grade or employing benchtop vibration isolation• Using 22 ft. X 22 ft. column-spacing• Concentrating fume hoods and utility risers into a central “wet zone,〞thus limiting horizontal mechanical distribution• Concentrating laboratory support areas into the central core of a laboratory structure, where utilities are available but daylight is not needed, thus enablinglab structures to be 110-132 feet wide• Utilizing dual-usage circulation/equipment cross-corridors through this central lab support zone, with sufficient width (typically 11 feet) to line the corridors with shared equipment while providing cross-circulation through the lab support zone• Utilizing open laboratory layout with one or more “ghost〞corridors for intra lab circulation• And, most importantly, concentrating non-laboratory functions into an adjoining, lower-cost structure (as discussed in detail above).To further control laboratory construction costs, non-standard fume hood sizes are minimized, “generic〞lab casework is specified, laboratory-grade movable tables substitute for fixed casework in some lab bays, building DI systems provide intermediate water quality (with localized water purity polishing in the lab, rather than building-wide),facility-wide piped services do not include gases that can be cost-effectively provided locally via canisters, and glass-wash facilities are consolidated -- typically, one glass wash facility for an entire laboratory building.Finally, our design philosophy leans toward generic, modular laboratories supported by a robust building infrastructure, rather than highly customized spaces with limited capacity to make later changes. This is an important trade off. Although some post-occupancy expenses may be necessary to “fine-tune〞a laboratory to a PI’s requirements, building infrastructure elements – typically over sized twenty percent, including HVAC supply ducts, exhaust system capacity, emergency generator capacity, and electric risers and service capacity – seldom limit the ability to modify labs to meet researcher needs.Structural and Foundation SystemsFor both cost-benefit reasons and past seismic performance, UC Irvine favors concrete shear wall or steel braced-frame structural systems. The correlating foundation systems depend on site-specific soil conditions. Past problems with undiscovered substrates and uncharacterized soil conditions are minimized through extensive, pre-design soil-testing. This minimizes risk to both the University and the design/build contractor.When feasible, design/build contractors are allowed flexibility to propose alternate structural or seismic-force systems. All structural system designs must pass a peer review, according to Regents’ policy. This process results in conservative structural design, and an associated cost premium. However, the seismic performance of University of California buildings constructed since this policy went into effect in 1975 appears to substantiate the value of the Regents’ Seismic Revi ew Policy.Structural vibration is carefully specified in research buildings where vibration-sensitive protocols and conditions must be maintained on above-grade floors. The most cost effective tools to control vibration are generally employed: first, to program vibration sensitive procedures at on-grade locations or to isolate them at the bench; second, to space columns at a distance that does not entail excessive structural costs. In laboratory 4buildings we typically utilize 22 ft. X 22 ft. column-spacing. Conversely, where vibration is not problematic a beam/column system can be cost-optimized and lighter floor loading can be tolerated. Design/build contractors are, accordingly, allowed more flexibility under such conditions.To control costs, UC Irvine avoids use of moment-resisting structures; unconventionalseismic systems; non-standard structural dimensions; inconsistent, unconventional, or non-stacking structural modules; and non-standard means and methods.Roofs and FlashingsUC Irvine specifies 20 year roofing systems and stainless steel or copper flashings whenever possible. At minimum, we specify hot-dip galvanized flashings.Why this emphasis on flashings? Our roof replacement projects typically double in cost when the old roofing is torn off and it is determined that the flashings have deteriorated. Moreover, many roof leaks of recent years have been due to faulty flashings, rather than roofing membranes or coatings, per se. Saving money on flashings is false economy. Another special roofing expe nse we may have to incur in order to attain the Regents’ Green Building Policy is that of reflective roofing. It is too early to understand the potential cost impact.中文翻译：建立标准和本钱加州大学欧文分校新建筑追求性能目标和适用的质量标准,影响资本本钱的工程。

英文文献Engineering cost managementProject cost control emphasis should be transferred to the project construction early days, is transferred to the project decision and design stage. Project cost control in construction projects throughout the entire process, the key lies in the pre construction investment decision-making with design phase, whereas in the investment decision is made, the key lies in designing. According to expert analysis: architectural design, in the preliminary design stage, design stage, construction design stage to the engineering effect were 75% ~ 95%, 35% ~ 75%, 5% ~ 35%; while in the construction phase, through the optimization of construction organization design, construction cost saving the possibility of only 5% to 10%. We should put the focus shifted to the design stage, in order to get twice the result with half the effort.Pay attention to the technical and economic optimization combination. The combination of technology with economy is most effective way to control engineering cost. China engineering fields for a long time did not do this. The lack of technical personnel economy idea, design thought is conservative, the design of the outcome of the economy are not fully reflect. Therefore, we should solve the problem is to improve economic efficiency as the goal, in the construction process, organization, technology and economy organic ground union rises. Through the economic analysis, comparative study and effect evaluation, correct processing of advanced technology and reasonable in economy between the relation of unity of opposites, strive to advanced technology under the conditions of economic rational, reasonable in economy based on advanced technology.Carry out "limitation is designed" method. To be consciously put the application of value engineering to the specific design, actively promote quota design in engineering design contract, by way of bidding. This has been proven in practice is an effective way, it is not only an economic problem, more precisely a technical and economic problems. This "limitation is designed" to effectively control the project cost. In order to make the "limitation is designed" to achieve the desired objectives, should be involved in the design personnel must be experienced skilled economic designer. Their design results must be practical, advanced and reasonable cost. Control of engineering cost on the other hand is the need for comparison, because the outcome is a process of gradual improvement, and not to decide, so the comparison is a measure of its practical, advanced and economical means.Do good project cost control in the process. ( 1) compilation of economic and feasible construction scheme. Before construction, construction enterprises should be combined with the construction drawings and the actual situation at the scene, their mechanical equipment, construction experience, the management level and technical specification acceptance criteria, a set of practical and feasible construction scheme. The construction scheme is engineering implementation of the programme of action. ( 2) to technical personnel, materials, machinery and personnel staff communicationand coordination. In the process of construction, construction technology, materials and mechanical personnel should cooperate closely, understand each other, to management as the core, to reduce costs for the purpose of. ( 3) to the project completion settlement. Strict supervision system. Control project cost effectively, in the early phase of the project shall be subject to supervision (including cost management ) system. Through analyzing the design process of supervision, make the design more reasonable, cost control to limit the scope of, accomplish truly with the smallest investment maximize output.Strict supervision system. Control project cost effectively, in the early phase of the project shall be subject to supervision (including cost management ) system. Through analyzing the design process of supervision, make the design more reasonable, cost control to limit the scope of, accomplish truly with the smallest investment maximize output.To establish and perfect the independent project cost advisory body, cultivate a Zhi De have both engineering team. To establish a real sense of independent engineering cost consulting agencies. Through improving the laws and regulations, normative behavior, separate government functions from enterprise management, the establishment of independent business partnership, share-holding system, the limited responsibility system and other forms of organization, an industry-based, diversified services integrated project consulting company, build and development and reform the engineering cost intermediary service institutions, make construction project management of a gradual transition by an independent specialized agency in charge of project cost whole process tracking management, truly between owner and contractor plays an intermediary role. To strengthen engineering cost consulting industry association construction, establish project cost consulting industry self-discipline mechanism, and constantly improve the Engineering Cost Association in engineering cost consulting industry status, to be truly representative of the interests of the majority of the industry practitioners, government and enterprises to become connection link and the bridge. At the same time to strengthen the project cost specialty in higher education and in service education. As a result of project cost management in construction projects and various economic interests are closely related, and the whole social economic activities play a very important role, it requires the cost engineering technical personnel should have different levels of knowledge, in addition to their professional knowledge and have a deep understanding, also deal with the design content, design process, construction technology, project management, economic laws and regulations have a comprehensive understanding of. Therefore, the project cost management, project cost per unit of society groups, has already obtained a cost engineer qualification personnel, in order to carry out plan, has the goal, multiple levels of continuing education and training, to understand and master Chinese bilateral agreements with countries project cost technology, regulations, management system and its development trend, to expand domestic and foreign exchanges, and actively participate in international or regional engineering activities, improve their professional quality, so that the current practitioners in intelligentstructure, theory and working experience three aspects can meet the needs of engineering cost management. Cost engineering professionals need to strengthen their own learning, in addition to the professional knowledge to upgrade, should also work in combination with a broad understanding and master the relevant engineering and technical expertise, educational organizations and industry regulatory bodies constitute a complete education system, so as to the field of engineering senior talent development to create good conditions.中文译文：工程造价与管理工程造价控制重点应转移到项目建设的前期，即转移到项目决策和设计阶段。

工程造价国外参考文献介绍工程造价是工程建设过程中合理使用资源、控制成本、保证质量的重要环节。

在国外，工程造价也受到广泛关注和研究。

以下是一些国外工程造价方面的参考文献介绍。

1.《Total Cost Management Framework: An Integrated Approach to Portfolio, Program, and Project Management》该书是美国斯坦福大学的教授 Edward Merrow 所著，介绍了一种全面的项目管理方法，涵盖了项目规划、预算、成本控制、风险管理等方面。

这本书被认为是工程造价管理领域的经典之作。

2. 《Construction Cost Management: Learning from Case Studies》该书由英国利兹大学的教授 Keith Potts 所著，以案例研究的方式介绍了工程造价管理的实践经验。

该书覆盖了建筑、土木、机电、水利等多个领域的工程案例研究，为读者提供了宝贵的经验和教训。

3. 《Construction Cost Estimating: Process and Practices》该书由美国工程师 Adam Ding 所著，主要介绍了工程造价估算的方法和实践。

该书详细阐述了工程造价估算的流程、方法和技巧，并通过案例分析和实例说明，让读者更好地理解和掌握工程造价估算的技术和方法。

4. 《Cost Engineering for Construction Projects》该书由德国工程师 Holger Svensson 所著，主要介绍了工程造价管理的理论和实践。

该书涵盖了建筑、土木、机电、水利等多个领域的工程造价管理，通过案例分析和实例说明，让读者更好地理解和掌握工程造价管理的技术和方法。

以上是一些比较有代表性的工程造价方面的参考文献，这些文献涵盖了工程造价管理的各个方面，对于从事工程造价管理的人员和相关专业人员来说，具有非常重要的参考价值。

工程造价英语文献以下是一篇关于工程造价的英文文献：Title: Construction Cost Estimation Techniques: A Review Abstract:Construction cost estimation is a crucial process in the construction industry, as accurate cost estimates are essential for project planning, budgeting, and decision-making. This paper provides a comprehensive review of various construction cost estimation techniques that are commonly used in practice. The review includes traditional methods, such as the unit cost method, the square foot method, and the assembly method, as well as modern methods, such as parametric cost estimation, expert judgement, and statistical analysis. The advantages and limitations of each technique are discussed, along with their applicability to different types of construction projects. The paper also highlights the importance of considering uncertainties and risks in cost estimation, and provides an overview of risk assessment techniques that can be used in conjunction with cost estimation models. The review concludes with recommendations for future research in the field of construction cost estimation.Keywords: construction cost estimation, techniques, traditional methods, modern methods, risk assessmentIntroduction:Construction cost estimation plays a critical role in the success of construction projects. Accurate cost estimates are essential for project planning, budgeting, and decision-making. However, costestimation is a challenging task due to the complexity and uncertainty inherent in construction projects. In recent years, there has been a growing interest in developing and implementing new cost estimation techniques to improve the accuracy and reliability of cost estimates. This paper aims to review the existing literature on construction cost estimation techniques and identify their advantages, limitations, and applicability in different contexts. Methods:A systematic literature review was conducted to identify relevant studies on construction cost estimation techniques. The search was performed using online databases and academic journals. The selected studies were then analyzed and categorized based on the type of construction cost estimation technique they described. Results:The review identified several traditional and modern cost estimation techniques that are commonly used in practice. Traditional methods, such as the unit cost method and the square foot method, are simple and easy to apply, but they may lack accuracy and flexibility. Modern methods, such as parametric cost estimation and expert judgement, take into account more variables and can provide more accurate cost estimates. However, they require more data and expertise. The review also highlighted the importance of considering uncertainties and risks in cost estimation, and described various risk assessment techniques that can be used in conjunction with cost estimation models.Discussion:The review revealed that there is no one-size-fits-all costestimation technique. The choice of technique depends on the characteristics of the construction project, the available data, and the expertise of the estimator. Moreover, there is a need for further research to develop more accurate and reliable cost estimation models, as well as to improve the integration of risk assessment techniques into cost estimation processes.Conclusion:Construction cost estimation is a complex and challenging task. This paper provides a comprehensive review of various cost estimation techniques used in practice and highlights their advantages, limitations, and applicability. The review also emphasizes the importance of considering uncertainties and risks in cost estimation, and suggests areas for future research. By improving the accuracy and reliability of cost estimates, construction professionals can make more informed decisions and ensure the success of construction projects.。

工程造价外国文献及译文以下为工程造价相关的外国文献及译文：1. "Engineering Cost Estimation and Control" by Philip E. Kesler and John M. Meredith。

《工程造价估算与控制》（Philip E. Kesler和John M. Meredith 著）。

2. "Cost Engineering for Construction Projects" by Ronald Klemencic。

《建筑工程造价工程》（Ronald Klemencic著）。

3. "Cost Estimating and Analysis for Engineering and Management" by Phillip F. Ostwald。

《工程和管理的成本估算和分析》（Phillip F. Ostwald著）。

4. "Construction Cost Engineering" by Stephen R. Devlen。

《建筑工程造价工程》（Stephen R. Devlen著）。

5. "Project Cost Control in Action" by Kim Heldman and William R. Duncan。

《项目成本控制实践》（Kim Heldman和William R. Duncan著）。

6. "Cost Estimating and Contract Pricing" by Michael D. Dell'Isola。

《成本估算和合同定价》（Michael D. Dell'Isola著）。

7. "Engineering Economics and Economic Design for Process Engineers" by Thane Brown。

工程造价专业毕业外文文献、中英对照中文翻译：工程造价专业毕业外文文献工程造价专业是一种重要的工程技术专业，主要负责工程投资的评估、选择和控制工程项目成本，以及项目质量、进度和安全。

因此，工程造价专业需要具备丰富的知识和技能，包括工程建设、经济学、管理学、数学、统计学等方面。

为了提高工程造价专业学生的综合能力，学习外文文献是不可或缺的步骤。

本文将介绍几篇与工程造价专业相关的外文文献，并提供中英文对照。

1）《The Role of Quantity Surveyors in Sustainable Construction》该文研究了数量调查师在可持续建筑中的作用，并深入探讨了数量调查师在项目的可持续性评估、营建阶段和运营阶段的角色和责任。

该文指出，数量调查师可以通过成本控制、资源利用、和材料选择等方面促进可持续建筑的发展，为未来可持续发展提供支持。

中文翻译：数量调查师在可持续建筑中的作用2）《Cost engineering》该文研究了造价工程的理论和实践，并提供了一系列工具和方法用于项目成本的控制和评估。

该文还深入探讨了工程造价和项目管理之间的关系，并提供了一些实用的案例研究来说明造价工程的实际应用。

中文翻译：造价工程3）《Construction cost management: learning from case studies》该文通过案例分析的方式来探讨建筑项目成本管理的实践。

该文提供了多个案例研究，旨在向读者展示如何运用不同的方法来控制和评估项目成本，并阐述了思考成本问题时需要考虑的多个因素。

中文翻译：建筑项目成本管理：案例学习4）《Project Cost Estimation and Control: A Practical Guide to Construction Management》该书是一本实用指南，详细介绍了在工程起始阶段进行项目成本估算的方法和技巧，以及如何在项目执行阶段进行成本控制。

外文翻译Construction projects, private and public alike, have a long history of cost escalation. Transportation projects, which typically have long lead times between planning and construction, are historically underestimated, as shown through a review of the cost growth experienced with the Holland Tunnel. Approximately 50% of the active large transportation projects in the United States have overrun their initial budgets. A large number of studies and research projects have identified individual factors that lead to increased project cost. Although the factors identified can influence privately funded projects the effects are particularly detrimental to publicly funded projects. The public funds available for a pool of projects are limited and there is a backlog of critical infrastructure needs. Therefore, if any project exceeds its budget other projects are dropped from the program or the scope is reduced to provide the funds necessary to cover the cost growth. Such actions exacerbate the deterioration of a state’s transportation infrastructure. This study is an anthology and categorization of individual cost increase factors that were identified through an in-depth literature review. This categorization of 18 primary factors which impact the cost of all types of construction projects was verified by interviews with over 20 state highway agencies. These factors represent documented causes behind cost escalation problems. Engineers who address these escalation factors when assessing future project cost and who seek to mitigate the influence of these factors can improve the accuracy of their cost estimates and program budgetsHistorically large construction projects have been plagued by cost and schedule overruns Flyvbjerg et al. 2002. In too many cases, the final project cost has been higher than the cost estimates prepared and released during initial planning, preliminary engineering, final design, or even at the start of construction “Mega projects need more study up front to avoid cost overruns.” The ramifica tions of differences between early project cost estimates and bid prices or the final cost of a project can be significant. Over the time span between project initiation concept development and the completion of construction many factors may influence the final project costs. This time span is normally several years in duration but for the highlycomplex and technologically challenging projects it can easily exceed 10 years. Organizations face a major challenge in controlling project budgets over the time span between project initiation and the completion of construction. The development of cost estimates that accurately reflect project scope, economic conditions, and are attuned to community interest and the macroeconomic conditions provide a baseline cost that management can use to impart discipline into the design process. Projects can be delivered on budget but that requires a good starting estimate, an awareness of factors that can cause cost escalation, and project management discipline. When discipline is lacking, significant cost growth on one project can raze the larger program of projects because funds will not be available for future projects that are programmed for constructionA history of past project experiences can serve one well in understanding the challenges of delivering a quality project on budget. Repeatedly, the same problems cause project cost escalation and much wisdom can be gained by studying the past. The Holland Tunnel was, when it opened in 1927, the longest underwater tunnel ever constructed and it was also the first mechanically ventilated underwater tunnel. Its initial cost estimate was made by the renowned civil engineer George Washington Goethals. A review of the Holland Tunnel project serves to highlight the critical issues associated with estimating the costs of large complex projects and the fact that even the most distinguished engineers have trouble assessing cost drivers beyond the physical characteristics of a project. Many times there is no recognition of the cost driver s operating outside the project’s physical configuration. A joint New York and New Jersey commission in 1918 recommended a transportation tunnel under the river “Urges new tunnel under the Hudson.” 1918; “Ask nation to share in tunnel to Jersey.” 1918. The automobile was emerging as the predominate means of transportation and it was decided that this tunnel should be for vehicular traffic. As a result the tunnel would employ new ventilation technologies to purge the exhaust gases produced by the internal combustion engine. Eleven designs were considered for the tunnel, most notably, one by the engineer recently responsible for finishing the Panama Canal, George Washington Goethals. He envisioned a single, bileveltunnel with opposing traffic on each level. Goethals made a planning project cost estimate of $12 million and 3 years for construction. World War I had consumed much of the nation’s steel and iron production, so his design made use of cement blocks as the tunnel’s structural shell. His design was the frontrunning plan “Hudson vehicle tube.” but he had responsibilities elsewhere and was not named chief engineer for the project. Clifford M. Holland was named to head the project along with a board of five consulting engineers “Name interstate tunnel engineers.” 1919. Holland came to the project with vast experience in constructing subways and tunnels in New York. The cost of the project was taken to be $12 million, Goethals’ planning estimate. Holland produced a report in February of 1920 based on his a nalysis of the Goethals’ design of the project. His findings were not what had been expected. Holland found • Goethals’ width of 7.47 m would not accommodate the volume of traffic.• Concrete blocks would not withstand the structural loads exerted on the t unnel.• The construction methods required by Goethals’ design were completely untried.• The estimated cost of construction was grossly low.• The work could not be completed in 3 years.The board of consulting engineers gave unanimous support for Holland’s analysis. Holland then presented a design of his own which was supported unanimously by the consulting engineers. Holland’s design, which was a major scope change, called for twin cast-iron tubes. One advantage was that construction would follow established methods of tunnel construction that had been implemented for rail tunnels under the East River and further up the Hudson. Holland estimated the cost at $28,669,000 “Asks $28,669,000 for Jersey tube.” 1920 and construction time at 31/2 years.Debate about the tunnel design continued for more than a year creating disagreements between the New York and New Jersey Commissions and delaying the work—a schedule change. A disagreement about awarding a contract on the New Jersey side further delayed the start of construction and added over half of a million dollars in cost. Construction started on the New York side in October of 1920 and inlate December 1921 the New Jersey portion of the tunnel was bid “Way all cleared for Jersey tunnel.” The mandated completio n date was December 31, 1926. The construction schedule had now grown to 5 years. Estimated project cost increased multiple times throughout the early years of construction as a result of scope creep, schedule delays, and inflation. Increased traffic forecast necessitate larger entrance/exit plazas and acquisition of more right of way “Vehicular tube is growing.” 1923. Then increases in material and labor costs had added another $6 million to the project inflation. By the beginning of 1924, reestimated costs had been increased by $14,000,000 “Vehicular tunnel cost up $14,000,000.” 1924 due to functional and aesthetic factors scope creep. More intricate roadway designs for approaches, widening of the approach roadways, and architectural treatments increased the costs more scope creep. Redesign of the ventilation system added 15.24 cm to the tunnel diameter and $4,422,000. Holland also decided to substitute cast-steel for castiron to increase the strength and safety factors of the tunnel more scope creep. Last, the New Jersey ventilation shafts had to be redesigned along with their corresponding foundations at a cost of $700,000 due to unexpected soil conditions unforeseen conditions. All of these changes increased the estimate to over $42.5 million. New funds were appropriated and it was believed that these were sufficient to complete the project, but by February of 1926, there was another increase of $3,200,000 “$3,200,000 more asked for tunnel.” The commission explained that the new costs were due to increases in labor and material costs challenge in controlling cost. At this time Holland died of heart failure and his assistant, Milton H. Freeman, took over as chief engineer only to die of pneumonia 4 months later. Ole Singstad, the designer of the ventilation system then became chief engineer and brought the project to completion. Having three different chief engineers within 5 months created confusion unforeseen events. In April of 1924 water rushed into one of the tunnels from a leak forcing workers to make a hasty escape more unforeseen conditions. A final appropriation was requested in early 1927 brought the total project cost to $48,400,000. On November 13 of 1927 the tunnel officially opened “Work on tunnel began 7 years ago.” MethodologyThe cost escalation factors that lead to project cost growth have been documented through a large number of studies. Studies have identified factors individually or by groups. Each factor presents a challenge to an agency seeking to produce accurate project cost estimates. As part of a larger study seeking to improve cost estimates and management of costs from project conception to bid day, a thorough literature review was conducted to identify factors that influence cost estimates Anderson et al. 2006. The literature review included exploration of research reports and publications, government reports, news articles, and other published sources. Upon completion of the literature review the factors were analyzed and categorized by the researchers into factors that drive the cost increases experienced by transportation construction projects. This was accomplished by triangulation where multiple investigators or data sources suggested the same factor. This categorization took the individual factors which had been identified in previous research and established a global framework for addressing the issue of project cost escalation. Upon final categorization the cost escalation factor framework was verified through triangulation of data from interviews with more than 20 state highway agencies SHAs around the nation . A previous project that supported identification of the factors had included telephone interviews with all 50 SHAs Schexnayder et al. 2003 . An interview instrument was prepared and tested initially during onsite interview with two SHAs. The revised interview instrument was then sent to the SHAs before the interview so that they could prepare. The interviews were conducted onsite for five SHAs through individual interviews and through a group “peer exchange.” The remaining interviews were conducted by telephone. In all cases, the researchers followed the interview protocol to ensure consistency in data collection. The resulting categorization of cost escalation factors can help project owners and engineering professionals focus their attention on the critical issues that lead to cost estimation inaccuracy.The triangulation analysis considered methodologies from past studies and interviews to create a categorization for the causes of cost escalation. A better understanding of the cost escalation factors is achieved through understanding theforces driving each factor or where the factor originates. With this understanding it is possible to design strategies for dealing with these cost escalation factors. The factors that affect the estimate in each project development phase are by nature internal and external. Factors that contribute to cost escalation and are controllable by the agency/owner are internal, while factors existing outside the direct control of the agency/owner are classified as external. The presentation order of the factors should not be taken as suggesting a level of influence is constructed to provide an over arching summary of the factors. It summarizes the factors into logical divisions and classifications and helps in visualizing how project cost estimates are affected. It is important to note that one of the factors points to problems with estimation of labor and material cost, but most of the factors point to “influences” that impact project scope and timing.中文译文私人和公共的建设项目，一直以来有成本增长的问题。

COST AND TIME CONTROL OF CONSTRUCTION PROJECTS:INHIBITING FACTORS AND MITIGATING MEASURES IN PRACTICEYakubu Adisa Olawale, Ph.D., MCIOB and Ming Sun, Ph.D. (Professor)AbstractDespite the availability of various control techniques and project control software many construction projects still do not achieve their cost and time objectives. Research in this area so far has mainly been devoted to identifying causes of cost and time overruns. There is limited research geared at studying factors inhibiting the ability of practitioners to effectively control their projects. To fill this gap, a survey was conducted on 250 construction project organisations in the UK, which was followed by face-to-face interviews with experienced practitioners from 15 of these organisations. The common factors that inhibit both time and cost control during construction projects were firstly identified. Subsequently 90 mitigating measures have been developed for the top five leading inhibiting factors - design changes, risks/uncertainties, inaccurate evaluation ofproject time/duration, complexities and non-performance of subcontractors were recommended. These mitigating measures were classified as: preventive, predictive, corrective and organisational measures. They can be used as a checklist of good practice and help project managers to improve the effectiveness of control of their projects.Keyword: Cost control, interview, practice, project control, project management,INTRODUCTIONIn the construction industry, the aim of project control is to ensure the projects finish on time, within budget and achieving other project objectives. It is a complex task undertaken by project managers in practice, which involves constantly measuring progress; evaluating plans; and taking corrective actions when required (Kerzner, 2003). During the last few decades, numerous project control methods, such as Gantt Bar Chart, Program Evaluation and ReviewTechnique (PERT) and Critical Path Method (CPM), have been developed (Nicholas 2001, Lester 2000). A variety of software packages have become available to support the application of these project control methods, for example Microsoft Project, Asta Power Project, Primavera, etc. Despite the wide use of these methods and software packages in practice, many construction projects still suffer time and cost overruns. In recent years, there have been numerous studies on the identification of influencing factors of project time and cost overruns worldwide. Mansfield et al (1994) carried out a questionnaire survey amongst 50 contractor, consultant and client organisations in Nigeria and found out that the most important variables causing construction delays and cost overruns are poor contract management, financing and payment of completed works, changes in site conditions, shortage of materials, imported materials and plant items, design changes, subcontractors and nominated suppliers. While the top variables causing only cost overruns were revealed as price fluctuation, inaccurate estimates, delays, additional work. Kaming et al (1997) identified factors influencing construction time and cost overruns on Cite as: Olawale, Y., and Sun M. (2010). “Cost and time control of construction projects: Inhibiting factors and mitigating measures in practice.”Construction Management and Economics, 28 (5), 509 –526. high-rise building projects in Indonesia through a questionnaire survey administered on 31 project managers. A total of 11 variables (design changes, poor labour productivity, inadequate planning, material shortages,inaccuracy of material estimate, skilled labour shortage etc) were identified for time overrun and seven (materials cost increased by inflation, inaccurate quantity take-off, lack of experience of project location, lack of experience of project type etc) for cost overrun. Kumaraswamy and Chan (1998) conducted a more extensive study in Hong Kong using 400 questionnaires after which follow up interviews were held. The study revealed the top ten causes of construction delays from the contractors’point of view as delays in design information, long waiting time for approval of drawings, poor site management and supervision, mistakes and discrepancies in design documents, etc. Similar survey studies were reported by Frimpong et al (2003) in Ghana and by Assaf and Al-Hejji (2006) in Sandi Arabia. In addition to questionnaire surveys, other researchers adopted a case study approach. Al-Momani (2000) examined 130 public projects in Jordan and concluded that the main causes of delays include changes initiated by designers, client requirement, weather, site conditions, late deliveries, economic conditions, etc. Hsieh et al (2004) conducted a statistical analysis in 90 metropolitan public work projects in Taiwan and identified problems in planning and design as main causes of change orders. Yogeswaran et al (1998) scrutinised 67 civil engineering projects in Hong Kong and suggested that at least a 15-20% time overrun was due to inclement weather. Based on analysis of 46 completed building projects in the UK, Akinsola et al (1997) identified and quantitatively examined factors influencing the magnitude and frequency of Cite as: Olawale, Y., and Sun M. (2010). “Cost and time control of construction projects: Inhibiting factors and mitigating measures in practice.”Construction Management and Economics, 28 (5), 509 –526. variations in building projects. These factors include: client characteristics, especially lack of prior experience and knowledge of construction project organization and the production processes; project characteristics, such as type, size, complexity and duration of the project; and project organisation factors, such as; design duration, percentage of design completed before tender, procurement and contract type, adequacy of information provided, and number of sub-contractors. While all the above studies, to various extents, helped with the better understanding of the problems associated with cost and time overruns in construction projects, there are some limitations. (1) Some of these studies are over 10 years old. There is a need for a more up to date investigation to reflect any development in recent years. (2) Most of the studies were carried out outside the UK. Although construction projects worldwide share some common characteristics, there are also some country specific conditions. For example, it is highly unlikely that “shortage of materials”and “import of materials”are major factors in the UK. Therefore, a UK based study will help to identify issues most relevant to the contemporary practice in this country. (3) Some of the reviewed surveys had relatively small sample sizes, which may affect the reliability of their results. (4) All the studies focused on identifying factors that have the biggest influence on project costs and time. They did not discuss the degrees of difficulty in controlling these factors in practice. There seems to be an implicit assumption that the most important factors are also those most difficult to control. This needs to be explicitly validated. (5) Finally, most existing studies stopped at the identification of the influencing factors, but did not progress Cite as: Olawale, Y., and Sun M. (2010). “Cost and time control of construction projects: Inhibiting factors and mitigating measures in practice.”Construction Management and Economics, 28 (5), 509 –526. onto finding ways of mitigating the identified problems. These observations underlie the rationale for this study. Its aim is to identify the main inhibiting factors of project control in practice in the UK and then to develop some mitigating measures to assist project managers better control their projects.RESEARCH METHODSThis research adopts a combination of quantitative and qualitative methods. It was conducted in two stages. The first stage was conducted using a quantitative method through a questionnaire survey in a bid to generate information from a large sample population. The second stage of the study was conducted using the qualitative method using semi-structured interviews. The reasons for using the interview in addition to the questionnaire survey were: to triangulate data obtained from the questionnaire survey; to enhance, expand and create depth to the results of the questionnaire survey by investigating and elaborating on some of the issues highlighted; and to explore the experiences of the sample population in relation to the topical issues revealed after analysis of the data obtained from the questionnaire survey.Questionnaire SurveyThe aim of the survey is toestablish the current common practice of time and cost control in the UK construction industry, including control methods and software applications being used by practitioners as well as inhibiting factors. It started with a thorough review of existing studies that revealed a lot of issues on construction Cite as: Olawale, Y., and Sun M. (2010). “Cost and time control of construction projects: Inhibiting factors and mitigating measures in practice.”Construction Management and Economics, 28 (5), 509 –526. project time and cost overruns, project control tools and techniques and latest thinking and new developments in the field of construction project control. This led to the development of a questionnaire made up of 22 multiple choice questions. The questionnaire was divided into three sections:Section one was background information which was targeted at obtaining information on the general particulars of the respondents and their organisation, such as the experience ofthe respondnets, their position within the organisation, the type of project embarked on by the organisation etc.The second section was about time overrun, project planning and time control practice such the frequency of time overrun experienced, the techniques used for planning and time control, the factors that hampers respondents from effectively controlling their projects etc .while the third section contained similar questions but specific to cost control practices. A total of 250 questionnaires were administered; 150 to the top construction companies in the UK by company turnover and the remaining 100 to the top construction project consultancies in the country by the number of professional staff employed and company fee earnings. This list was obtained from the Building magazine annual league tables. The league tables did not contain the addresses of the companies so an online web search was conducted to find their addresses and contact details. Telephone calls were subsequently made to these companies to confirm the addresses and to find out the type of hierarchy and structure that exists within the organisation. This enabled the questionnaires to be sent to the appropriate Cite as: Olawale, Y., and Sun M. (2010). “Cost and time control of construction projects: Inhibiting factors and mitigating measures in practice.”Construction Management and Economics, 28 (5), 509 –526. department. To supplement this, the name of a construction director, manager or the appropriate personnel with a huge responsible for the management of construction projects in the organisation was obtained to ensure that the questionnaires went to the correct addresses and addressed to the appropriate personnel. This ensured a very good response as 110 questionnaires (44% response rate) were returned. Tables 1 and 2 show the profile of the practitioners that responded to questionnaire on behalf of their companies. Nearly 72% of the respondents that completed thequestionnaires were directors or senior managers, commercial managers. As would be expected from their roles, these respondents also had significant years of experience in the construction industry. Nearly half (48%) of respondents had more than 25 years of experience. This showed that there was great depth in the experience possessed by the respondents.DISCUSSIONSThis study approached the influencing factors of project control from a new perspective. As previously mentioned a lot of previous studies in the area of project control have mainly been focused at cost and time overruns most especially their causes. Their findings are often influenced by the specific context of each study. Many researchers came up with quite different lists of top factors that have major impact on cost and time. The survey results of this study reflect the current views of the leading practitioners in the UK. Another aspect that distinguishes this study from previous ones is that the survey during the first stage of the study seeks to identify the main factors that hamper project managers’ability to control cost and time not just those that might have the biggest impact. It is interesting to find that the top five inhibiting factors are all project internal elements. This is in contrast to previous studies where many external aspects are often cited as most important factors, such as inflation, material shortage, unforeseen ground conditions, inclement climate, etc. Cite as: Olawale, Y., and Sun M. (2010). “Cost and time control of construction projects: Inhibiting factors and mitigating measures in practice.”Construction Management and Economics, 28 (5), 509 –526. (Arditi, 1985; Kaming et al, 1997; Mansfield et al, 1994, Kumaraswany and Chan, 1998). The possible explanation for this is that although external factors are usually difficult to control or even beyond the control of project managers, the frequency of their occurrence is general low. On the other hand, internal factors are persistent and require constant controlling.The mitigating measures are distilled from in-depth interviews with very experienced project management practitioners. They are not simply selected from current best practice. They reflect what should be done to improve the current project control practice. For example in-depthinterviews found that there has been a general decline in the production of detailed design for construction projects; and this is perceived as one of the greatest cause of design changes, the foremost bottleneck during the project control process. It was also revealed that there is often a lack of distinction between a design change and a design development leading to argument among project partners. In-depth interviews also brought to light the fact clients contribute to the problem of project cost and time control by imposing unachievable and unrealistic time scales. These revelations led to the development of a number of mitigating measures, some of the measures developed on the back of these problems include; measures 8 (designing the project to a great detail at the outset whenever possible), 1 (clear distinction between a design change and a design development at the outset of a project), 37 (educating and advising client on alternative if an unachievable/unrealistic project timescale is stipulated), 38 (having the courage to refuse unrealistic project timescale by clients unwilling to yield to Cite as: Olawale, Y., and Sun M. (2010). “Cost and time control of construction projects: Inhibiting factors and mitigating measures in practice.”Construction Management and Economics, 28 (5), 509 –526. professional advise). It was also revealed that quite often, the non-performance of subcontractorsis not necessarily the fault of subcontractors but due to lack of effective management by the main contractor. The mitigating measures that stemmed from this include; 66 (properly directing the subcontractor to ensure they know what is expected of them in relation to the project), 68 (puttinga system in place for early identification of non-performance in subcontract works/packages in order to nip it in the bud as soon aspossible) and 69 (utilising performance measurements e.g. S-curve, KPI to monitor the output/performance of subcontractors on their work package). The development of the mitigating measures was also built on the existing studies on good but often generic project management practices. For example several previous studies revealed that the wooly area of design change and design development is one of the key reasons why design change is considered a barrier to effective cost and time control. To combat this, Kartam et al (2000) recommended that end user requirement should be closely coordinated in the early phase of the project and more attention should be placed on managing this requirement during the construction phase. This is similar to some of the mitigating measures identified in this study but this study has gone further by making them more specific to the project control process. For example measures 8, 15 and 18 in table 12 have been made specific for mitigation of design changes during the project control process. Another mitigating measure for design change is measure 11 (agreeing and putting in place change management procedure before the commencement of projects, incorporating this Cite as: Olawale, Y., and Sun M. (2010). “Cost and time control of construction projects: Inhibiting factors and mitigating measures in practice.”Construction Management and Economics, 28 (5), 509 –526. into the contract if possible). This measure was also buttressed by a number of studies in different ways. For example Lee et al (2005) identified project change management as a critical practice that has important impacts on both cost and schedule performance or projects. Ling etal (2009) in the study of key project management practices affecting project performance found that the most significant practices that are significantly correlated with project performance relate to scope management and recommended that emphasis must be given to scope management in order to achieve superior project performance. Similarly Zou and Lee (2008) used multiple one-way ANOV A and linear regression to investigate the effectiveness of change management practices elements in controlling project change cost and found amongst others that using change management practices is truly helpful in lowering the proportion of change cost in project actual cost. On another hand, Kog et al (1999) identified key determinants for construction schedule performance and discovered amongst others, that havinga constructability programme is a key determinant to construction schedule performance. A constructability programme was described in the study as the application of a disciplined and systematic optimisation of construction-related knowledge during the planning, design procurement and construction stages by knowledgeable experienced construction personnel who are part of the team. Measures 34, 35, 36 and 42 in table 14 developed for the mitigation of inaccurate evaluation of project time duration are specific practices that will go a long way at ensuring the development of a constructability programme. Cite as: Olawale, Y., and Sun M. (2010). “Cost and time control of construction projects: Inhibiting factors and mitigating measures in practice.”Construction Management and Economics, 28 (5), 509 –526. The mitigating measures are the result of a three staged research process. It will be wrong to assume that these measures are identified from only a small number of interviews. In fact, the interview is just the last stage of the development of these measures in a three stage process involving, literature review, questionnaire survey, intellectual thinking and finally the interviews which acted as a way of putting some practicalityin the mitigating measures by drawing from the real life experiences of interviewees. It should also be pointed out that the interviews did not ask practitioners about their experience of a single project or a single company but drew on theirexperiences of many projects they have worked on. This approach has been adopted by related studies such as Kartam et al (2000), Gao et al (2002) and Sohail et al (2002). For example Sohail et al (2002) in the research aimed at developing monitoring indicators for urban micro contracts began by studying archival records of projects, then used a questionnaire survey to generate more data, conducted interviews to gain more in-depth understanding of the of the situation after which the monitoring indicators were eventually developed by inferences made from analysis of interviews, archival records and questionnaires. While these mitigating measures can contribute to the improvement of project control in practice, there are also some limitations. There is a need for integrating the implementation of these measures into project control models. Some of these measures outline what need to be done, but do not address how they can be achieved. Issues like these need to be investigated in future research. Cite as: Olawale, Y., and Sun M. (2010). “Cost and time control of construction projects: Inhibiting factors and mitigating measures in practice.”Construction Management and Economics, 28 (5), 509 –526.CONCLUSIONSA combination of questionnaire survey and in-depth interviews has been used to provide useful information on issues surrounding project control in practice in the UK. Issues such as the degree of application of project controls, the most commonly used time and cost control techniques, supporting software packages, frequency of time and cost overrun, the leading inhibiting factors to effective cost and time control, the reasons for this and measures that can be used for their mitigation were brought to light.The top five factors inhibiting time and cost control in construction practice in the UK was revealed as design changes, risks and uncertainties; inaccurate evaluation of project time/duration; complexity of works and; non-performance of subcontractors. Design change is the single most important factor considered by practitioners as hindering the ability to control not only time of construction projects but also cost. In fact, it is found that there is a high level correlation between the inhibiting factors for cost control and time control. Following the identification of the inhibiting factors, 90 mitigating measures are established to address potential problems caused by the top five inhibiting factors. The measures can be broadly classified as preventive, predictive, corrective and organisational measures. These measures are by no means exhaustive as there will obviously be numerous practices out there that have not made the list. It is also worth noting that the measures may seem obvious to the experienced practitioner but will be useful to the less experienced and people new to the project management profession. The study should be viewed as the first Cite as: Olawale, Y., and Sun M. (2010). “Cost and time control of construction projects: Inhibiting factors and mitigating measures in practice.”Construction Management and Economics, 28 (5), 509 –526. effort of developing solutions for mitigating leading cost and time control inhibiting factors. Clearly, further development is needed to cover more inhibiting factors beyond the top five. In addition, the effectiveness of these mitigating measures during the project control process needs to be investigated in future research.REFERENCESAibinu, A. and Jagboro, G. (2002) The effects of construction delays on projectdelivery in Nigerian construction industry. International Journal of ProjectManagement, 20 (8), 593-599.Akinsola, A., Potts, K., Ndekugri, I., Harris, F. (1997) Identification and evaluationof factors influencing variations on building projects. International Journal ofProject Management, 15 (4), 263-267.Century, Ascot.Cooke, B. and Williams, P. (2004) Construction planning programming and control.Blackwell publishing, Oxford.Dlakwa, M. M. and Culpin, M. F. (1990). Reasons for overrun in public sectorconstruction projects in Nigeria. International Journal of Project Management, 8(4),237–240.Egbu, C., Young, B., Torrance, V. 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