Awad S. Hanna

Quantifying Performance for the Integrated Project Delivery System as Compared to Established Delivery Systems

AbstractIntegrated project delivery (IPD) is an emerging construction project delivery system that collaboratively involves key participants very early in the project timeline, often before the design is started. It is distinguished by a multiparty contractual agreement that typically allows risks and rewards to be shared among project stakeholders. Because IPD is becoming increasingly popular, various organizations are expressing interest in its benefits to the architecture/engineering/construction (AEC) industry. However, no research studies have shown statistically significant performance differences between IPD and more established delivery systems. This study fills that missing gap by evaluating the performance of IPD projects compared to projects delivered using the more traditional design-bid-build, design-build, and construction management at-risk systems, and showing statistically significant improvements for IPD. Relevant literature was analyzed, and a data collection instrument was developed an...

A fuzzy logic approach to the selection of cranes

This paper presents a fuzzy logic approach to select the best crane type in a construction project from the main crane types, namely, mobile, tower and derrick cranes. Each factor of the project is classified as being dynamic or static according to whether the factor does or does not depend on the particular project. Linguistic information about the suitability of each crane type with respect to each factor of the project is translated into either fuzzy sets (for static factors) or fuzzy if–then rules (for dynamic factors). The fuzzy rules are then aggregated into a fuzzy relation between the space of factor property and the space of crane efficiency. In a particular project the experts describe the property as well as the relative importance of each factor. The rules are then fired using the max–min extension principle, and the resulting efficiencies are aggregated with their importance weights. The process identifies the best crane as the one with the highest expected overall efficiency.

AutoPave: towards an automated paving system for asphalt pavement compaction operations

Abstract Asphalt pavement density from roller compaction is a crucial factor in ensuring satisfactory pavement performance. Proper and uniform compaction of the pavement mat is essential in achieving the desired final compacted density. There is a necessity to investigate existing pavement construction practices, and provide more cost-effective modifications to the current scenario. Automation of the paving operation can increase the efficiency and quality of the operation, lead to reductions in overall project costs and time, and enhance pavement life. A system can be developed through algorithmic planning and real-time guidance strategies, and the development of a semi-automated path-planning and real-time guidance system that aims towards automating the paving operation. This system accepts relevant paving project inputs, generates appropriate path plans for the compactor, performs a graphical visualization of the generated path plan, and offers real-time guidance capabilities using Global Positioning Systems (GPS) technology. This system, named AUTOPAVE (v1.0), was developed in Microsoft Visual Basic™ programming language and offers a user-friendly and interactive graphical interface. The proposed new system will incorporate state-of-the-art GPS technology to standardize paving operations that are more amenable to rigorous quality control, and can result in considerable reductions in cost and time involved in asphalt pavement construction projects. This system was tested on several actual paving projects, and many operational issues related to the functioning of the system were successfully overcome.

Concrete Formwork Systems

Concrete formwork - an introduction horizontal formwork systems - hand-set systems slab form design horizontal formwork systems - crane-set systems selection criteria for horizontal formwork system vertical formwork systems - crane dependent systems wall form design vertical formwork systems - crane-independent systems selection criteria for vertical formwork systems.

The impact of change orders on mechanical construction labour efficiency

Change orders impact many areas of a construction project. However, the impacts that change orders have on labour efficiency are much harder to quantify than other impacts and therefore are a significant risk to contractors. Little research has been completed in the past quantifying these impacts, so disputes are common between owners and contractors regarding the actual cost of change. This study used data from 43 projects to develop a linear regression model that predicts the impact of change orders on labour efficiency. The input factors needed for the model are (1) total actual project hours, (2) total estimated change hours, (3) impact classification, and (4) timing of change. The model calculates the labour loss in efficiency for a particular project so that owners and contractors will better understand the true impact of change on labour efficiency. The research is limited to the mechanical trade, but does include specific work in plumbing, HVAC, process piping, and fire protection.

Quantitative Methods for Design-Build Team Selection

Use of design-build (DB) contracting by transportation agencies has been steadily increasing as a project delivery system for large complex highway projects. However, moving to DB from traditional design-bid-build procurement can be a challenge. One significant barrier is gaining acceptance of a best value selection process in which technical aspects of a proposal are considered separately and then combined with price to determine the winning proposal. These technical aspects mostly consist of qualitative criteria, thus making room for human errors or biases. Any perceived presence of bias or influence in the selection process can lead to public mistrust and protests by bidders. It is important that a rigorous quantitative mathematical analysis of the evaluation process be conducted to determine whether bias exists and to eliminate it. The paper discusses two potential sources of bias – the evaluators and the weighting model – in the DB selection process and presents mathematical models to detect and remove biases should they exist. A score normalization model deals with biases from the evaluators; then a graphical weight space volume model and a Monte Carlo statistical sampling model are developed to remove biases from the weighting model. The models are then tested and demonstrated using results from the DB bridge replacement project for the collapsed Mississippi River bridge of Interstate 35W in Minneapolis, Minnesota.

State of Practice of Building Information Modeling in the Mechanical Construction Industry

AbstractThe North American construction industry has seen a decline in productivity for decades due to underlying problems such as lack of team collaboration, less initial design input, and higher building systems complexity. These problems are most visible in labor-intensive trades, such as mechanical contractors. Within the last decade, building information modeling (BIM) has emerged as a potential solution to these problems. This paper highlights the state of BIM practice in the mechanical construction industry. Through an extensive survey and interview process, this research resulted in three key outcomes. The first is that 58% of mechanical contractors have less than three years of BIM experience and consider themselves as beginners in the use of BIM. Second, BIM implementation cost for these contractors is 1% to 2% of their total project cost estimate. Third, more than 70% of mechanical contractors agree that BIM reduces field conflicts and improves coordination. These factors can assist mechanical ...

Planned and unplanned schedule compression: the impact on labour

Constructors confronted with the need to compress or accelerate a construction schedule face the potential for extreme difficulties. Unfortunately, a limited knowledge base exists for determining the techniques, methods, or concepts to be employed in mitigating these potential negative outcomes of lower labour productivity rates and higher project costs. This paper explores the impacts of planned and unplanned schedule compression on labour productivity. Additional impacts of schedule compression related to project costs and schedule duration are also evaluated. Telephone interviews and questionnaire surveys primarily were used as the means for data collection to determine which methods of schedule compression identified are most effective in each of the aforementioned areas. Members of the National Electrical Contractors Association (NECA) were used as the data source for this investigation because of their diversified experience and because of the support received from NECA management. A number of sched...

State of Practice of Building Information Modeling in the Electrical Construction Industry

AbstractFor decades, the North American construction industry has seen a decline in productivity due to many underlying reasons. Moreover, the construction industry in general and electrical construction companies in particular struggled with coordination and productivity. Within the last decade, building information modeling (BIM) has become the means for a real solution to these problems. This paper attempts to highlight the practices and state of BIM in the electrical construction industry. Through an extensive survey and interview process, this research has provided three main conclusions. First, electrical contractors have not yet advanced their implementation of BIM, with 59% of respondents having three years or less experience with BIM. Second, in order to maintain a positive outcome for the use of BIM on a project, contractors should maintain one to three staff members as BIM specialists, adding a cost of 2% or less from the total project cost to implement BIM. Third, BIM does indeed reduce field ...

Using the Earned Value Management System to Improve Electrical Project Control

In many cases, disorganized cost and schedule tracking practices, as well as inaccurate data collection, cause many projects to experience distress and possible profit loss. This paper introduces an earned value management system that allows electrical contractors to monitor construction progress, perform forecasts on the project, uncover problems occurring on-site, and respond to problems in the project as early as possible. This paper also presents a case study, along with its results, to supplement the application of the earned value management system. In the case study, several progress reports for the earned value system were used, including the field personnel loading curve, Hanna’s control points, S-curves, performance factor profiles, and work-hour forecasts. Results from the analysis showed that early determination of probable project outcome is possible with reasonable forecasting accuracy. Early warning signs are discussed and explained by the author. Using an earned value management system can...