Editor’s Note

“Addressing Pricing: Value-Bidding for Engineers and Consultants,” by Sturts and Griffis, presents a unique treatment of competitive bidding theory as applied to pricing engineering services. The authors conclude that there is a need for a systematic method of evaluating potential job opportunities and determining fair market prices of engineering services. This hybrid model, “value-bidding,” refocuses the competitive bidding model from a fee-based selection criteria to a value-based selection criteria. The resulting analytical model enables engineers to analyze many different factors while having a successful outcome.

A critical issue in public private partnerships in international infrastructure development is the selection of the right private sector partner. This necessitates a best-value source selection methodology, in which the establishment of a set of appropriate selection criteria is a prerequisite. Zhang assesses criteria important in selecting the best partner, and classifies them into four evaluation packages in “Criteria for Selecting the Private-Sector Partner in Public-Private Partnerships.” The relative importance of these evaluation packages and the relative significance of the criteria within each package have been statistically analyzed based on a survey of worldwide PPP expert opinions.

The build-operate-transfer approach in China is still in its infancy. Unwary users face many pitfalls, and such obstacles impede more extensive application of this modality, attributable to the complexities of the BOT approach. Chan, Chen, Messner, and Chua propose two systems concepts to help manage this complexity in “Interface Management for China’s BOT Projects.” Expert opinion was elicited on the criticality of the interfaces in China’s BOT Generic Process Model as well as the effectiveness of selected interface management measures.

The financial evaluation of a privatized infrastructure project is complex and challenging because of the risks and uncertainties due to the large size, long contract duration, non-recourse financing, multiple project participants with different motives and interests, and the complexity of the contractual arrangements. Zhang develops a methodology for capital structure optimization and financial viability analysis that reflects the characteristics of project financing, incorporates simulation and financial engineering techniques, and aims at win-win results for both public and private sectors in “Financial Viability Analysis and Capital Structure Optimization in Privatized Public Infrastructure Projects.”

The cost–schedule integration technique makes extensive use of project estimate and schedule data to make detailed predictions of cash flows for individual projects. However, its accuracy is largely a function of the quality of the data available to the model. Chen, O’Brien, and Herbsman present two complementary methods to evaluate the ability of existing CSI models to accurately predict cash flows in “Assessing the Accuracy of Cash Flow Models: The Significance of Payment Conditions.” The authors then conclude by recommending extensions of CSI models to increase the models’ accuracy.

According to the author, continuous flight auger piles do not receive sufficient research attention although they are widely used in the United States, the United Kingdom, and other countries in the world. Therefore, Zayed focuses on describing the CFA pile installation features, exploring its construction methods, and determining the factors that affect the CFA pile productivity and cost in “Productivity and Cost Assessment for Continuous Flight Auger (CFA) Piles.” Several models are designated to assess the CFA pile’s cycle time, productivity, and cost using a deterministic approach.

Tamate, Suemasa, and Katada focus on the phenomenon of ground instability causing mobile cranes to overturn in “Analyses of Instability in Mobile Cranes Due to Ground Penetration by Outriggers.” The authors perform various types of analysis including experiments in order to investigate the influence of ground penetration by outriggers on the stability of mobile cranes. In the end, a method of evaluating the risk of mobile-crane overturning is proposed by using the maximum value of both the supporting surface’s failure risk and the kinetic risk due to ground penetration.

Bored piles, which are vital elements for bridge construction, have a large number of factors which oversee productivity and cost estimation processes. These factors create many problems to the time and cost estimators of such processes. Zayed and Halpin design a study to diagnose such problems and assess productivity, cycle time, and cost for pile construction using an artificial neural network in “Pile Construction Productivity Assessment.” The ANN models are validated and their robustness in output assessments is probed.

Chua and Goh present a statistical framework based on the Modified Loss Causation Model to understand and analyze construction incidents in “Poisson Model of Construction Incident Occurrence.” The MLCM is separated into two basic components: the random component and the systematic component, with the former being represented by a probability density function. In particular, the authors propose that the PDF can be represented by the Poisson distribution, for several reasons.

Prefabrication, preassembly, modularization, and off-site fabrication, collectively termed as “prework” or PPMOF, have become more viable with recent advances in design and information technologies. Song et al. identify those factors influencing decisions on the use of prework and current industry practices for evaluating the applicability of prework on industrial projects in “Considering Prework on Industrial Projects.” The authors then present a decision framework to assist industry practitioners with evaluating the applicability of prework on their project.

Hanna, Taylor, and Sullivan present an analysis of the impacts of extended duration overtime on construction labor productivity in “Impact of Extended Overtime on Construction Labor Productivity.” The results show a decrease in productivity as the number of hours worked per week increase and∕or as project duration increases. The research focuses on labor-intensive trades such as the electrical and mechanical trades. The effects of overtime were determined by data collected from 88 projects across the United States by means of a questionnaire.

Bernhold addresses a known weak point in protecting buried utilities from damage—the lack of accurate as-built drawings—in “Automatic As-Built Generation with Utility Trenchers.” It has been suggested to take advantage of enabling technologies to automatically create as-built drawings relying on electronic sensory data collected in real-time from operating machinery. A significant portion of the paper discusses the development of a spatially integrated trencher, a prototype that was subsequently used to execute field experiments.