Model for Predicting the Performance of Project Managers at the Construction Phase of Mass House Building Projects

The need to match project managers’ (PMs) performance measures onto projects of both unique and similar characteristics has long since been acknowledged by researchers. The need for these measures to reflect the various phases of the project life cycle has also been contended in the recent past. Here, a competency-based multidimensional conceptual model is proposed for mass house building projects (MHBPs). The model reflects both performance behaviors and outcome in predicting the PMs’ performances at the conceptual, planning, design, tender, construction, and operational phases of the project life cycle. Adopting a positivist approach, data elicited for the construction phase is analyzed using multiple regression techniques (stepwise selection). Out of a broad range of behavioral metrics identified as the independent variables, the findings suggest the best predictors of PMs’ performances in MHBPs at the construction phase are: job knowledge in site layout techniques for repetitive construction works; dedication in helping works contractors achieve works schedule; job knowledge of appropriate technology transfer for repetitive construction works; effective time management practices on house units; ability to provide effective solution to conflicts, simultaneously maintaining good relationships; ease with which works contractors are able to approach the PM and volunteering to help works contractors solve personal problems. ANOVA, multicollineriality, Durbin–Watson, and residual analysis, confirm the goodness of fit. Validation of the model also reflected reasonably high predictive accuracy suggesting the findings could be generalized. These results indicate that the model can be a reliable tool for predicting the performance of PMs in MHBPs.     

Optimal Construction Site Layout Considering Safety and Environmental Aspects

A good site layout is vital to ensure the safety of the working environment and effective and efficient operations. Site layout planning has significant impacts on productivity, costs, and duration of construction. Construction site layout planning involves identifying, sizing, and positioning temporary and permanent facilities within the boundary of the construction site. Site layout planning can be viewed as a complex optimization problem. Although construction site layout planning is a critical process, systematical analysis of this problem is always difficult because of the existence of a vast number of trades and interrelated planning constraints. The problem has been solved using two distinct approaches: Optimization techniques and heuristics methods. Mathematical optimization procedures have been developed to produce optimal solutions, but they are only applicable for small-size problems. Artificial intelligent techniques have been used practically to handle real-life problems. On the other hand, heuristic methods have been used to produce good but not optimal solutions for large problems. In this paper, an optimization model has been developed for solving the site layout planning problem considering safety and environmental issues and actual distance between facilities. Genetic algorithms are used as an optimization bed for the developed model. In order to validate the performance of the developed model, a real-life construction project was tested. The obtained results proved that satisfactory solutions were obtained.     

Causes of Delay in the Planning and Design Phases for Construction Projects

Problems of delay occur in all phases of construction projects. While most previous studies have focused on finding causes or overcoming delays in the construction phase, few studies have analyzed delay problems in the planning and design phases. The main purpose of this study is to identify and rank delay causes in the planning and design phases. A structured questionnaire was sent to engineers at the A/E companies for public construction projects in Taiwan. Based on 95 valid responses, this study identified the delay causes and analyzed the importance and frequency of delays using the relative importance index. Analytical results reveal that “changes in client’s requirement” are the main causes of delays in both planning and design phases. The finding is good justification for many public clients who usually change their requirements during the planning and design phases that really delay construction projects.     

Effect of Preconstruction Planning Effort on Sheet Metal Project Performance

The complexity of construction industry requires the identification of work tasks and the coordination of interactions among them. As a result, construction planning is considered to be one of the most critical steps toward success and is the main focus of past research. Consequently, little research has been performed regarding the preconstruction planning, which is the planning completed by the contractor in the period between project award and project execution. This paper focuses on sheet metal preconstruction planning, primarily that of mechanical and heating ventilations and air conditioning contractors. The research was completed in three phases: phase one gathered data on the current state of preconstruction planning, phase two developed a model sheet metal preconstruction planning process to be used by sheet metal contractors, and phase three validated the model preconstruction planning process. Based on project data collected for this research, projects that used a planning process similar to the model process performed more successfully—they achieved an average profit margin of 23% while projects that were poorly planned experienced an average profit margin of ?3%.     

Factors Affecting Engineering Productivity

Engineering performance has a major impact on subsequent project phases, such as procurement and construction, and thus, has the potential to affect the overall project outcome. This study utilizes metrics and a database from the Construction Industry Institute (CII) benchmarking and metrics program to investigate relationships between factors thought to affect direct engineering labor productivity during detailed engineering. Collaborating with industry practitioners, quantitative assessments were analyzed with industry input through various CII committee meetings and industry forums. Significant correlations are found between engineering productivity and project size, project type, project priority, and phase involvement. Correlations are also found between degree of modularization, funded front-end planning effort, and quality management and engineering productivity. These findings extend and, in some cases, contradict previous research.     

Dynamic Site Layout Planning Using Approximate Dynamic Programming

Dynamic site layout planning requires identifying and updating the positions of all temporary construction facilities such as offices, storage areas, and workshops over the entire project duration. Existing models do not guarantee global optimal solutions because they focus on optimizing the planning and layout of successive construction stages in a chronological order, without considering the future implications of layout decisions made in early stages. This paper presents the development of an approximate dynamic programming model that is capable of searching for and identifying global optimal dynamic site layout plans. The model applies the concepts of approximate dynamic programming to estimate the future effects of layout decisions in early stages on future decisions in later stages. The model is developed in three main phases: (1) formulating the decision variables, geometric constraints, and objective function of the dynamic site layout planning problem; (2) modeling the problem using approximate dynamic programming; and (3) implementing and evaluating the performance of the model. An evaluation example is analyzed to illustrate the use of the model and demonstrate its capabilities in generating global optimal solution for dynamic site layout planning of construction projects.     

Nondominated Archiving Multicolony Ant Algorithm in Time–Cost Trade-Off Optimization

Time–cost trade-off analysis is addressed as an important aspect of any construction project planning and control. Nonexistence of a unique solution makes the time–cost trade-off problems very difficult to tackle. As a combinatorial optimization problem one may apply heuristics or mathematical programming techniques to solve time–cost trade-off problems. In this paper, a new multicolony ant algorithm is developed and used to solve the time–cost multiobjective optimization problem. Pareto archiving together with innovative solution exchange strategy are introduced which are highly efficient in developing the Pareto front and set of nondominated solutions in a time–cost optimization problem. An 18-activity time–cost problem is used to evaluate the performance of the proposed algorithm. Results show that the proposed algorithm outperforms the well-known weighted method to develop the nondominated solutions in a combinatorial optimization problem. The paper is more relevant to researchers who are interested in developing new quantitative methods and/or algorithms for managing construction projects.     

Site Layout Planning using Nonstructural Fuzzy Decision Support System

Site layout planning can affect productivity and is crucial to project success. However, as construction is heterogeneous in the nature of its organizations, project designs, time constraints, environmental effects, etc., site layout planning for each project becomes unique. Affected by many uncertainties (variables) and variations, site layout planning is a typical multiobjective problem. To facilitate the decision-making process for these problems, a nonstructural fuzzy decision support system (NSFDSS) is proposed. NSFDSS integrates both experts’ judgment and computer decision modeling, making it suitable for the appraisal of complicated construction problems. The system allows assessments based on pairwise comparisons of alternatives using semantic operators that can provide a reliable assessment result even under the condition of insufficient precise information.     

Footbridge: Project to Implement Management Functions at AASTMT

Recently, the construction industry has introduced fundamental changes for integration of functions during the different project phases. The design/build approach that integrates design and construction is a prominent example of such changes. Consequently, modifications are necessary in civil engineering education to prepare students to deal with the demands of the new environment. This paper documents a graduate project offering students the opportunity to study planning, design, procurement, and construction on a real-life project, and to deal with the problems of integrating these functions. The project is a steel footbridge of 10-m span and 1.5-m width. The bridge is located on the campus of the Arab Academy for Science, Technology, and Maritime Transport, Alexandria, Egypt. The project was accomplished by a group of five students with the participation of an industrial sponsor who provided the necessary funds to construct the bridge and the required expertise for fabrication and erection. The nature and scope of the project provided a good balance between the task scope and the constrained time and effort of students. To a large extent, the students dealt with a real project and experienced real situations.     

Benchmarking Productivity Indicators for Electrical/Mechanical Projects

Labor-intensive industries such as the electrical and mechanical trades are considered high risk due to the high percentage of labor costs. Because of this high risk, it is important for contractors in these industries to closely track labor costs on projects and compare these costs to industry benchmarks. In this paper, benchmark indicators for these industries are established on the basis of actual project data. These benchmarks include the relationship between the percent complete or percent time and cumulative work hours or cost, project size and duration, project size and average man power, project size and peak man power, and average versus peak man power. These relationships were developed using regression analysis. Man power loading charts and the related S-curves were developed from actual project data. The man power loading charts and the related S-curves are useful for resource planning and for tracking progress on a construction project. They can be used to show the cause-and-effect relationship between projects impacted by outside factors and normal labor productivity.     

Budget and Schedule Success for Small Capital-Facility Projects

The project management environment of small capital projects is unique in many ways. One unique aspect is the total administrative burden they place on resources for approvals, reviews, and execution relative to the overall value of the capital works program. Administratively, many organizations follow a prescribed approval process for all capital project expenditures regardless of size. For these organizations, small capital projects constitute 80% of the projects executed per year but only account for approximately 16% of the capital projects’ budget expenditures. The opportunity to improve organizational performance through more effective project execution on small capital projects could provide substantial savings within individual small capital-project programs. This paper reports on data collected from active small project-program personnel as well as project success factors identified in the literature. By means of analysis and comparison between the data collected and the project success factors identified in the literature, a comprehensive list of small-project success factors was developed. Sixteen factors were identified from project success factors listed by various authors in project management literature. These factors are used as a baseline for evaluating the findings from a questionnaire and interview process conducted with a diverse group of project management personnel. The paper concludes that the factors on small projects are not unlike those on large projects. The key differences noted were related to the frequency of process implementation, which affects the timing and execution of the project work phases for small projects. The area holding the greatest potential for performance improvement for small projects is the front-end planning process.     

Stochastic Construction Time-Cost Trade-Off Analysis

Traditional time-cost trade-off analysis assumes that the time and cost of an option within an activity are deterministic. However, in reality the time and cost are uncertain. Therefore, in analyzing the time-cost trade-off problem, uncertainties should be considered when minimizing project duration or cost. Simulation techniques are useful for analyzing stochastic effects, but a general strategy∕algorithm is needed to guide the analysis to obtain optimal solutions. This paper presents a hybrid approach that combines simulation techniques and genetic algorithms to solve the time-cost trade-off problem under uncertainty. The results show that genetic algorithms can be integrated with simulation techniques to provide an efficient and practical means of obtaining optimal project schedules while assessing the associated risks in terms of time and cost of a construction project. This new approach provides construction engineers with a new way of analyzing construction time∕cost decisions in a more realistic manner. Historical time∕cost data and available options to complete a project can be modeled, so that construction engineers can identify the best strategies to take to complete the project at minimum time and cost. Also, what-if scenarios can be explored to decide the desired∕optimal time and∕or cost in planning and executing project activities.     

Modeling and Forecasting Construction Labor Demand: Multivariate Analysis

This paper presents the development of advanced labor demand forecasting models at project level. A total of 11 manpower demand forecasting models were developed for the total project labor and ten essential trades. Data were collected from a sample of 54 construction projects. These data were analyzed through a series of multiple linear regression analyses that help establish the estimation models. The results indicate that project labor demand depends not only on a single factor, but a cluster of variables related to the project characteristics, including construction cost, project complexity attributes, physical site condition, and project type. The derived regression models were tested and validated using four out-of-sample projects and various diagnostic tests. It is concluded that the models are robust and reliable, which merit for contractors and HKSAR government to predict the labor required for a new construction project and facilitate human resources planning and budgeting, and that the methodology used may be applied to develop equally useful models in other subsectors, and in other countries.     

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.     

Model for Understanding, Preventing, and Resolving Project Disputes

Based on the comparative analysis of 24 construction disputes, this paper presents a process model that explains the development of disputes. The model examines the combined effect of project uncertainty, contract, working relations, and problem solving effectiveness on the development of disputes. The model develops a classification of problem situations, and identifies the problem-solving requirements and the potential for dispute in each situation. The model indicates that the prevention of complex, high cost disputes depends more on the planning and problem solving ability of the project organization, and less on the contractual terms. The paper identifies the following actions that can reduce the number and severity of claims: reduction of project uncertainty, reduction of contractual problems, reduction of opportunistic behavior, increased the project organization's problem-solving ability, and use of alternative dispute resolution methods to reduce resolution costs.     

Improvement Algorithm for Limited Space Scheduling

Selecting construction methods, scheduling activities, and planning the use of site space are key to constructing a project efficiently. Site layout and activity scheduling have been tackled as independent problems. Their interdependence is often ignored at the planning stage and may be dealt with—if at all—when construction is underway. Problems that may have had easy solutions if dealt with earlier, may then be expensive to remedy. This paper addresses the combined problem termed “space scheduling” and presents an algorithmic time-space trade-off model for adjusting activity durations and start dates to decrease the need for space over congested time periods. The model characterizes resource space requirements over time and establishes a time-space relationship for each activity in the schedule, based on alternative resource levels. An example illustrates the presented algorithm that generates a feasible space schedule.     

Dynamic Planning and Control Methodology for Design∕Build Fast-Track Construction Projects

A dynamic planning and control methodology is developed by integrating the applications of axiomatic design concepts, concurrent engineering concepts, the graphical evaluation and review technique (GERT), and the system dynamics modeling technique. The goal of the proposed methodology is to help create a dynamic project plan for design∕build fast-track civil engineering and architectural projects where unforeseen changes can be absorbed in the project schedule without creating major interruptions. The axiomatic design concepts are applied to formulate and evaluate various work methodologies, and to create a project plan based on the selected work methodology. The concept of concurrent engineering is adapted to develop a fast-tracking framework based on the task production rate, the upstream task reliability, and downstream task sensitivity to the upstream error. The GERT diagramming scheme is used to calculate the project duration probabilistically by incorporating the possible branches and loops in the project. The system dynamics modeling technique is applied to analyze the causality links of relevant factors in the construction system, and further identifies the important variables that determine the success of a particular overlapping strategy. Consequently, with a rigorous and systemized methodology to help project planning, potential problems can be addressed early before construction. The overall increase in productivity and efficiency as a result of a better planning process can consequently promote the competitiveness of the construction industry.     

Critical Space Analysis

The construction space scheduling problem has received relatively little attention from researchers and practitioners. We now have sophisticated methods of planning and analyzing the sequence of tasks within the work breakdown structure through time, but the problem of planning where on site those tasks are to be executed is not well-supported especially as those spaces are dynamic as the project progresses. We know that congestion on site reduces output and generates hazards, yet construction planners presently have to rely upon experience and intuition. The research reported here presents a decision support tool for construction project planners to help them address the space scheduling problem. After a review of recent developments in construction space scheduling, the concept of critical space analysis is presented. This forms the basis of decision support tools presented for marking up available space, allocating tasks to spaces, and analyzing and optimizing space loading in relation to the critical path—what we call space-time broking. Requirements capture and evaluation reports from construction planners suggest that the tools presented here have immediate practical relevance. The paper will, therefore, be of interest to both practitioners and researchers.