Journal of Construction Engineering and Management

Trenching to install deep gravity sewers and drains in medium-to high-strength rock requires large and heavy rock trenchers that produce high levels of vibrations that may affect the structural integrity of nearby utilities and buildings. Although not every vibration causes damage, owners often believe that their structures have been harmed by rock excavation. The resulting disputes can waste a great deal of time and money. In an effort to reduce structural damage and associated disputes, this paper provides guidelines for the safe distance between rock trenchers and nearby buildings and underground structures. Vibration data at different distances from the trencher centerline were collected from five trenching projects in Northwest Ohio. The data analysis suggests a moderate relationship between the vibration level and the distance from the source of vibration. In addition, the risk of damage to nearby structures dissipates significantly and quickly as the distance from the point of excavation increases. Rock trenching should not take place closer than $1.50\mathrm{m}$ for buried structures and $1.00\mathrm{m}$ for residential buildings. Beyond this safe distance, damage to nearby structures should not take place.

Assessing the impact of delay and resolving disputes are contentious issues since courts and administrative boards do not specify standard delay analysis practices. First, the advantages and disadvantages of widely used delay analysis methods, including the as-planned versus as-built, impact as-planned, collapsed as-built, time impact, and productivity analysis methods are summarized. Fifty-eight claim cases associated with time-based disputes in government work during the 1992–2005 period are extracted and analyzed to observe issues in time-based claims, including the reasons why they occur and the common practices in their resolution. The effects of various factors on the selection of a delay analysis method are examined. These factors include the type of schedule used, the schedule updating practice, the use of existing versus newly created schedules, and the availability of expertise, information, time, and funds. A project management system that makes use of regularly updated network schedules, and that maintains adequate project records should allow a scheduling expert to select a delay analysis method that would make a claim quite convincing.

A new scheduling and cost optimization model for high-rise construction is presented in this paper. The model has been formulated with a unique representation of the activities that form the building’s structural core, which need to be dealt with carefully to avoid scheduling errors. In addition, the model has been formulated incorporating: (1) the logical relationships within each floor and among floors of varying sizes; (2) work continuity and crew synchronization; (3) optional estimates and seasonal productivity factors; (4) prespecified deadline, work interruptions, and resource constraints; and (5) a genetic algorithms-based cost optimization that determines the combination of construction methods, number of crews, and work interruptions that meet schedule constraints. A computer prototype was then developed to demonstrate the model’s usefulness on a case study high-rise project. The model is useful to both researchers and practitioners as it better suits the environment of high-rise construction, avoids scheduling errors, optimizes cost, and provides a legible presentation of resource assignments and progress data.

Methods to quantify and evaluate quality become important when lump sum and performance contracts replace traditional unit-price or cost-plus contracts. Here, a combined graphical and mathematical method is described along with its results when applied on a Swedish rail maintenance contract with incentives. The regression analysis tools in the Excel software were used. The result of the incentives was that train delay decreased about 10% and the number of technical errors decreased about 20%. The improved quality took place without cost increase. The good relation between the owner and the contractor did not suffer from the rise of efficiency. On the contrary, it was improved. With minor modifications and clarifications the owner now intends to use it for in-house contracting, as the case studied, as well as when outsourcing to private companies. With other performance indicators, the elaborated method and lessons learned should be applicable also for other sectors, where a contractor assuring a specified service level during a period of time is paid a bonus depending on degree of fulfillment.

Rapid construction projects and processes will become increasingly important as customers demand better project management performance and globally, as countries plan for and respond to the aftermath of natural and/or unnatural disasters. For use in expedited projects (as well as traditional projects), a rapid universal safety and health system (RUSH) was designed, developed, deployed, and evaluated. For its inaugural application, the RUSH was applied to a $106\text{-}\text{hour}$ construction project. Results from an initial application included a safe build in approximately $5\text{days}$ without recordable incidents. More importantly, lessons were learned by a multidisciplinary team of researchers who observed safety $24∕5$ for the life of the project. Lessons learned and recommendations for future research are provided as a result of this experience.

This paper describes how problem patterns can be identified and analyzed for diagnosing and/or predicting nonconformance of constructed facilities. This will enable appropriate actions to be taken for eradicating the causes of nonconformance and preventing their recurrence and/or their occurrence. A structure has been defined for representing construction projects information and organizing knowledge extracted from past experience to facilitate the analyses. Pattern analyses have been directed at deriving root cause classes of problems including (1) design, which relates to the assigned specifications, methods, and/or procedures; (2) execution, which involves errors or the inability to execute tasks; and (3) external, which includes unforeseen events or accidents. Highway pavement construction has been selected as an application and illustrative domain. Expert knowledge related to low density and roughness of constructed pavements has been assembled and organized to support the analyses. The approach provides a generic mechanism to carry out integrated root cause analyses with design/planning, construction, and quality management information. Its application has been demonstrated and validated using case studies from different construction domains.

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.

The interactive, complicated system environment of a construction site renders conventional site layout planning and scheduling techniques to be inadequate in coping with materials handling system design in construction. In this paper, we present a university-industry joint endeavor for improving the effectiveness of the materials handling system on a precast viaduct construction project in Hong Kong by implementing the simplified discrete-event simulation approach (SDESA) along with its computer platform resulting from recent research. How to apply the simulation methodology of SDESA is elaborated step by step. Particular emphasis is placed on procedures of establishing a simulation model, validation of the simulation model, design of simulation experiments, and analysis of simulation results. With process flowchart, site layout plan, and process animation produced in a view-centric simulation environment, it is straightforward to establish, validate, and communicate the operations simulation. The research team convinced the project director, as well as field managers, of the functionality and effectiveness of operations simulation. The knowledge derived from simulation added to experiences of site managers in materials handling system design. With the aid of simulation, even junior engineers would be capable and confident to draw up an actionable construction plan that would lead to enhancement of cost effectiveness and productivity in the field.