Contractor Process Improvement for Enhancing Construction Productivity

This paper presents a regression model that relates job site productivity to process improvement initiatives (PIIs) executed both before and during construction. Applied during early project stages, this model helps industry practitioners to predict the expected value of labor productivity based on certain inputs related to preconstruction planning and construction execution. The model demonstrates the strong relationship of project performance to a variety of PIIs including design completeness, definition of a project vision statement, testing oversight, and project manager experience and dedication. The correlational research methodology targeted 75 projects representing approximately $274.53 million in civil construction. The data collection effort considered 45 PIIs (independent variables) using quantitative and qualitative measures. The modeling technique involved the use of multiple linear regression, a method that exploits available data from multiple, independent sources to focus on specific outcomes. The model was developed directly from contractor specific information and subjected to rigorous statistical analysis. The model provides project managers as front line industry practitioners with a deliberate yet practical approach to project management and productivity enhancement. The modeling results include verification analysis and a discussion of the model’s usefulness and limitations.     

System Model for Analyzing Design Productivity

Many engineering design companies collect data such as person hours to manage projects. But the relationships between operational variables and performance are usually not thoroughly analyzed and interpreted. This paper proposes a system model and procedure to relate influence variables to project productivity. The model was tested by analyzing 190 projects of an engineering consulting company. The relationships between design productivity and various input and process variables were identified and interpreted. For example, project size has a negative relationship with productivity, while the effect of quality assurance/quality control on productivity is not clear. Based on documented data and derived information, this model can help companies gain operational insight and thus improve productivity and profitability.     

Measuring and Modeling Labor Productivity Using Historical Data

Labor productivity is a fundamental piece of information for estimating and scheduling a construction project. The current practice of labor productivity estimation relies primarily on either published productivity data or an individual’s experience. There is a lack of a systematic approach to measuring and estimating labor productivity. Although historical project data hold important predictive productivity information, the lack of a consistent productivity measurement system and the low quality of historical data may prevent a meaningful analysis of labor productivity. In response to these problems, this paper presents an approach to measuring productivity, collecting historical data, and developing productivity models using historical data. This methodology is applied to model steel drafting and fabrication productivities. First, a consistent labor productivity measurement system was defined for steel drafting and shop fabrication activities. Second, a data acquisition system was developed to collect labor productivity data from past and current projects. Finally, the collected productivity data were used to develop labor productivity models using such techniques as artificial neural network and discrete-event simulation. These productivity models were developed and validated using actual data collected from a steel fabrication company.     

Quantitative Definition of Projects Impacted by Change Orders

Change, defined as any event that results in a modification of the original scope, execution time, or cost of work, is inevitable on most construction projects due to the uniqueness of each project and the limited resources of time and money available for planning. Change may occur on a project for a number of reasons, such as design errors, design changes, additions to the scope, or unknown conditions. For each change, contractors are entitled to an equitable adjustment to the base contract price and schedule for all productivity impacts associated with the change. Changes may or may not have an impact on labor productivity. Existing literature uses subjective evaluation to determine whether the project is impacted. Projects impacted by change cause the contractor to achieve a lower productivity level than planned. The focus of this paper is to quantify whether an electrical or mechanical project is impacted by a change order. Through statistical hypothesis testing, groups of factors that correlate with whether a project is impacted by change orders were identified and used to develop a quantitative definition of impact. Logistic regression techniques were used to develop models that predict the probability of a project being impacted. The results of this research show that percent change, type of trade, estimated and actual peak manpower, processing time of change, overtime, overmanning, and percent change related to design issues are the main factors contributing to the project impact.     

Nature of Engineering Consulting Projects

Engineering consulting firms usually collect data such as cost and man-hour expenditures. Although these data help analyze project profit and productivity, they lack the information on the project nature to examine work and analyze the root causes of performance. This study investigates the nature of engineering consulting projects in terms of uncertainty and equivocality (U&E). A questionnaire was designed to collect project U&E data from 108 project managers. The U&E scores were analyzed, further linked to and tested on a consulting firm’s profit, productivity, project type, phase, duration, and owner data. It is found that project nature does not affect profit or productivity; engineering design work needs more data acquisition and analysis than problem definition and interpretation. Other results show insightful patterns about engineering projects that can be useful references to the engineering services industry.     

Best Practices for Integrating the Concurrent Engineering Environment into Multipartner Project Management

The use of the Internet, e-mail, and other technologies has been steadily filtering into the building process, creating a concurrent engineering (CE) environment, and enabling collaborative efforts in the building process. The concurrent engineering environment is established by a variety of tools, including internet accessible servers, e-mail, mobile telephones, and many other existing CE tools. Organizations involved in the construction process recognize the need for assessment of benefits resulting from CE tools, but find the evaluation of these benefits difficult and complicated. The project presented in this paper, “project management and organization in the concurrent engineering environment (ProCE),” is applicable to both researchers and practitioners. The ProCE project developed a measuring model, which may be used by future researchers in this area, attempted to measure benefits derived from using the CE environment in construction design and project management routines, and developed guidelines for best practice implementation by practitioners, based on four case studies. The project included the measurement of both the quantitative and qualitative benefit of CE environment implementation in building construction projects using tools that were readily available through application service providers. Measurement of cost and other quantifiable benefits have been extensively studied. Therefore, the majority of the discussion in the current paper will address the ProCE project’s measurement of qualitative benefits.     

Project Delivery Systems and Project Change: Quantitative Analysis

Design/build has become one of the favored project delivery methods in the engineering construction industry. Numerous studies have advocated the use of design/build over the traditional design/bid/build delivery approach. A comprehensive analysis of 67 global projects from the Construction Industry Institute's database shows that design/build projects may not provide all the benefits to project performance. The study found timesaving was a definitive advantage of design/build project delivery, but, the positive effects of cost and productivity changes were not convincing. Based on the results of the study, the project management expertise and experience of the contractor may have a greater impact on project performance outcomes than focusing on project delivery strategy only.     

Utility-Function Model for Engineering Performance Assessment

Engineering and design activities constitute a critical link in a project’s life cycle. Thus, an efficient project control system requires an instrument to measure and assess engineering performance among different projects. In conventional industry practices, the measurement of engineering performance is usually tied to the production of design documents during the detailed design phase of the project. Realizing the far-reaching impacts of engineering activities, researchers in the past have investigated other comprehensive measures of engineering performance that address the entire project life cycle. As part of a study for the Construction Industry Institute, this particular research employs a multiple attribute utility function method for the collective assessment of engineering performance in construction projects. The paper begins with a summary of previous studies in the area of engineering performance measurement and assessment. Afterwards, the concept of engineering performance is thoroughly explained. The paper then reviews the background and basic theories of using utility functions in assessing engineering performance, along with an illustrative example of the functionality of this approach. The paper goes on to show the development of the utility function model for the industrial construction sector through expert opinion and real project data. The use of the model is further illustrated in the assessment of total and relative engineering performance. Lastly, conclusions of this study are drawn and potential future work is pointed out.     

Risk Allocation by Law—Cumulative Impact of Change Orders

Change, defined as any event that results in a modification of the original scope, execution time, or cost of work, is inevitable on most construction projects due to the uniqueness of each project and the limited resources of time and money available for planning. There are many factors that may cause a change such as design errors, design changes, additions to the scope, or unknown conditions in the field. For each change, contractors are entitled to an equitable adjustment to the base contract price and schedule for all productivity impacts associated with the change. The focus of this paper is to outline the types of changes that can occur on a construction project and also to spell out the financial recovery possibilities that exist for the contractor for each type of change. There are many historical and current court decisions that shape the outcomes of such claims and determine who holds the risks associated with various project changes. Also, an effective cumulative impact claim contains certain vital elements upon which the final outcome will be determined by the legal system. Last, there are certain actions that a contractor and owner can do to either enhance or mitigate the effectiveness of a potential cumulative impact claim.     

What Is Preproject Planning, Anyway?

The importance of preproject planning in the capital facility delivery process and its potential impact on project success has long been recognized by industry practitioners. Nevertheless, the preproject planning process varies significantly throughout the construction industry from one organization to another, and from one business sector to another. This paper will summarize lessons learned from five research projects conducted during the past 14?years regarding the preproject planning process. These research projects were based on data from more than 200 capital projects, representing approximately 8.7 billion U.S. dollars; input from more than 500 industry practitioners; and reviews of the project planning processes used by more than 100 organizations. The positive relationship between thorough preproject planning and enhanced project performance is demonstrated. Findings are presented, including key requirements, processes, and scope definition elements that comprise thorough preproject planning. Similarities and differences in the scope definition of building and industrial projects are outlined. Conclusions of the research effort and recommendations to industry practitioners are provided.     

Benefits of Small Projects Team Initiative

Ordinarily, minimum design costs are associated with all construction projects regardless of their size or complexity. Consequently, the design costs are a higher percentage of the overall costs for small projects. This paper presents an analysis of the effectiveness of the Small Projects Team Initiative (SPTI) developed and implemented by the Seattle district of the U.S. Army Corps of Engineers. SPTI is intended to lower the design costs on construction projects where the design scope is simple and∕or the administrative and construction processes are somewhat routine. The Small Projects team consists of representatives from contracting, construction, engineering, and project management. This team produces specifications for selected projects with simplified design, design by shop drawing, and innovative contracting arrangements. Data from 77 projects completed within the Seattle district are compared with the data from 146 pre-SPTI jobs. Statistically confirmed benefits include reduced design costs and reduced schedule growth (when user requested changes are excluded). Lower median change-order rates are not confirmed, but further analysis of the nature of changes is recommended.     

Building Integrated Architecture/Engineering/Construction Systems Using Smart Objects: Methodology and Implementation

Integrated project systems hold the promise for improving the quality while reducing the time and cost of architecture/engineering/construction (AEC) projects. A fundamental requirement of such systems is to support the modeling and management of the design and construction information and to allow the exchange of such information among different project disciplines in an effective and efficient manner. This paper presents a methodology to implement integrated project systems through the use of a model-based approach that involves developing integrated “smart AEC objects.” Smart AEC objects are an evolutionary step that builds upon past research and experience in AEC product modeling, geometric modeling, intelligent CAD systems, and knowledge-based design methods. Smart objects are 3D parametric entities that combine the capability to represent various aspects of project information required to support multidisciplinary views of the objects, and the capability to encapsulate “intelligence” by representing behavioral aspects, design constraints, and life-cycle data management features into the objects. An example implementation of smart objects to support integrated design of falsework systems is presented. The paper also discusses the requirements for extending existing standard data models, specifically the Industry Foundation Classes (IFC), to support the modeling of smart AEC objects.     

Integrating Constructability into Project Development: A Process Approach

The National Cooperative Highway Research Program initiated a research project to develop a constructability review process (CRP) for transportation facilities. The basic objective of this research was to develop a systematic approach and methodology for constructability reviews. This paper describes the development of a CRP that meets the National Cooperative Highway Research Program's research objectives. A process approach is followed to integrate constructability improvements into project development for transportation projects. A function modeling tool is used to portray the interface between the CRP and the project development process. The function modeling tool captures constructability functions and information necessary to perform these functions. The research method to develop the CRP is presented. The CRP has three phases corresponding to planning, design, and construction of a transportation project. Seven constructability functions are performed in each phase. The model was tested using two transportation projects of different complexity.     

Cost Information Model for Managing Multiple Projects

Construction companies must deal with several projects at once, but a system to manage multiple projects is not fully developed yet. The first step towards developing such system is to design an information model that is suitable for managing multiple projects. This paper presents the cost-based project modeling (CBPM) method in contrast to the traditional activity-based project modeling methods. The CBPM uses cost as a core of the model along with other project information organized around it. The CBPM serves as a platform for integrating project information from multiple projects. Various types of construction costs are hierarchically modeled to generate corporate-wide information such as project performances, cash flows, and other predictive indicators. Based on the information model, an object-oriented database was developed to contain cost data across several projects. In the model, a module that connects to external systems is built into the model to enhance interactivity with the legacy systems and the industry standards. A prototype system was developed and tested with actual project data to validate the information processing capabilities of the model. The findings from the test indicate construction cost can be an excellent medium that can organize various types of information of multiple projects.     

Resident Engineering in Power Plant Construction

The resident engineering scope has broadened on recent power plant projects. Providing the technical and administrative support necessary for plant construction is a key requirement for successful projects. The elements of this responsibility and the activities required are described. Critical activities by the resident engineering organization in each of the project phases are described. Three approaches to the structuring of this organization (field, area, and discipline) are presented and described. The importance and benefits of recognizing each of these tasks and providing adequate staffing are emphasized.     

Criticism of CPM for Project Planning Analysis

Published criticism in recent years concerning the inadequacy of Critical Path Method (CPM) as a project planning tool is identified and grouped under six major headings with reference to the publications in which the criticism were contained. These are answered from the writer's field experience and from experiences published by other authors. The object of the analysis is to see whether or not CPM as a project planning tool can meet the required functions of planning in construction, including consideration of legal and contractual framework and the complex and interdisciplinary nature of the project environment. The analysis reveals that, despite numerous criticism, project and construction planning should be done using CPM scheduling. Main factors affecting successful planning are realistic estimation of the productivity of crews in the context of expected job‐management efficiency conditions, and inclusion of sufficient time buffers between dissimilar trades. CPM is found to be equally useful as a planning tool for linear or repetitive projects. The limitations of this technique are identified in terms of the defined planning functions in the engineering phase of capital projects. A broad model for management of the engineering phase in revenue‐generating projects is suggested.     

Structural Equation Model of Construction Contract Dispute Potential

This paper presents the results of a structural equation model (SEM) for describing and quantifying the fundamental factors that affect contract disputes between owners and contractors in the construction industry. Through this example, the potential impact of SEM analysis in construction engineering and management research is illustrated. The purpose of the specific model developed in this research is to explain how and why contract related construction problems occur. This study builds upon earlier work, which developed a disputes potential index, and the likelihood of construction disputes was modeled using logistic regression. In this earlier study, questionnaires were completed on 159 construction projects, which measured both qualitative and quantitative aspects of contract disputes, management ability, financial planning, risk allocation, and project scope definition for both owners and contractors. The SEM approach offers several advantages over the previously employed logistic regression methodology. The final set of structural equations provides insight into the interaction of the variables that was not apparent in the original logistic regression modeling methodology.     

Embodying Product and Process Flexibility to Cope with Challenging Project Deliveries

Four factors make it challenging to manage semiconductor fabrication facility (“fabs”) projects: technical complexity of the product design, need to compress the project duration, need to reduce upfront costs, and unexpected project changes. The strategies employed by practitioners to cope with these challenges form an intricate puzzle. We empirically develop a framework that provides a structure for helping to solve this puzzle, which comprises two principles: investing upfront in a flexible product design and structuring a flexible process. Empirical findings reveal that project teams make commitments early on by overdesigning but also postpone critical decisions by differentiating the scope of their work. Project teams employ other strategies such as increasing communication, using modular architectures, engaging in four-dimensional computer-based modeling, and fabricating components and subsystems off-site. Our analysis yields understanding on the purposes and performance tradeoffs of these strategies, and on how they embody the two principles. Project managers may find the framework useful when deciding which strategies best suit other equally challenging projects.