Construction Management & Economics

Shtub, Avraham

doi: 10.1080/01446198800000023pmid: N/A

The problem of scheduling a project for which expensive, long-lead inventory items have to be ordered from outside vendors is addressed. A logic aimed at minimizing the cost of such projects is presented along with an illustrative example. The logic is based on adding a material management module to the CPM analysis, evaluating the feasibility of the CPM schedule, and rescheduling the project in case long-lead items make the schedule generated by CPM infeasible. An attempt to integrate CPM and material management in a large-scale construction project is reported and possible extensions of this research are suggested.

Ndekugri, Issaka E.; McCaffer, Ronald

doi: 10.1080/01446198800000024pmid: N/A

The construction industry has been increasingly recognizing the need for more effective exchange of information between project participants. Not only have the manual systems failed to satisfy this need but the computer packages which have sprung up have also not allowed adequately for such communication. Integration of project information can optimize the operations of the industry as they exist currently. An even more promising but less immediate benefit of such integration is that it will form the necessary foundation for tools that advanced technology has the potential to produce. Such tools include simulation systems, knowledge-based systems and robotics which are very much in their infancy. A necessary step towards achieving the desired integration is to map out the characteristics of the flow of the information. This article analyses the flow of information among the management functions of the construction contractor.

Touran, Ali; Taher, Khalid A. H.

doi: 10.1080/01446198800000025pmid: N/A

Queuing theory applications in the field of earth-moving operations are reviewed. Using queuing theory and simulation techniques, a model is developed that can predict the productivity of one pusher and a fleet of scrapers under a given set of operating conditions. A computer program is developed for this purpose that interfaces Gaarslev's Queuing Model Program and Caterpillar's Vehicle Simulation Program. The new system can consider the effect of variable inter-arrival times and bunching and road and machine conditions. The developed computer system allows the user to perform a sensitivity analysis by varying the number of scrapers, thus determining the optimum fleet size based on the lowest cost per cubic yard of production.

Pain, James; Bennett, John

doi: 10.1080/01446198800000026pmid: N/A

This paper presents the results of a detailed study of projects using the JCT With Contractor's Design (WCD) form of contract. Initially 49 projects were investigated to discover how the WCD contract is being used: for what kind of projects, by whom, in what circumstances, and what management approaches are being used. Fourteen projects were then selected to be investigated in more detail on their performance in terms of time, cost, quality and management. The variables were assessed in absolute terms and were then compared to what might have been expected if the contract had been managed in the conventional manner, i.e. using the JCT 80 Standard form of building contract. The conclusion of the study was that out of all the WCD projects investigated none had experienced serious problems and only a small proportion had encountered any difficulties at all in using the WCD approach.

Laufer, A.; Tucker, R. L.

doi: 10.1080/01446198800000027pmid: N/A

Who should be assigned the task of planning a construction project and within what time-frame poses serious problems. Choosing between the likely candidates — manager or staff specialist and their respective strengths and weaknesses — is fraught with pitfalls. The awards and penalties linked to long lead-time planning as against short-term planning befog the decision process. Many companies are vexed by the dilemmas resulting from any solution to the ‘who’ and ‘when’ questions but by sidestepping or overlooking them they invite deficiencies with dire consequences. After an analysis of these issues the article proposes a new approach for the design of the construction planning process.

Runeson, G.

doi: 10.1080/01446198800000028pmid: N/A

This paper is a statistical analysis of the distribution of tenders and how it can be derived from the distribution of estimators' cost rates. It derives equations to explain the distribution of unit and elemental rates which are found to depend on the contribution of the task to the total cost, labour content and procurement method. It further demonstrates that while there is considerable co-variance between unit rates, there is no such interdependence between either elemental or subcontractor rates. This means that the central limit theorem can be used to forecast the distribution of tenders.

doi: 10.1080/01446198800000029pmid: N/A

doi: 10.1080/01446198800000030pmid: N/A