Scheduling Optimization of None Repetitive Construction Projects Under Constrained Resources

Abstract

In Sudan, the clients, contractors and consultants (Three Main Parties) of the construction industry are generally suffering from project time overrun specifically in the case of limited resources. This ultimately leads to overall project cost overrun. Within this context, the objectives of this research are twofold: 1- To plan and control none repetitive project time through scheduling and time optimization while considering constrained resources. 2- To develop a heuristic based on experience of Sudanese construction industry to optimize scheduling of none repetitive projects. To achieve the optimum balance between the increasing need for minimum project time completion while the project is subjected to limited resources, this study developed a heuristic model for none repetitive projects applicable within the Sudanese construction industry. Ten cases were studied for actual none repetitive construction projects that have been executed in Khartoum and other major towns in Sudan. Each project was described in details (i.e. number of activities , resources, durations, target time of completion , expected cost and so on) The actual studying models-ASM (project as case studies) were built up, then Primavera program was used as a simulator tool that made it possible to produce simulation product models-SPM. This model was then adapted using sixteen selected heuristics and was then applied to the ten mentioned projects, Statistical and operation research tools were then used in combination with existing heuristics and the common practices in construction industry in Sudan. Lindo program as a decision making program is also used which made it possible to reach the optimum solution of increasing needed time at its minimum rate to complete the project under resources limitation case. Then the results were evaluated as follows: - The optimum solution of increasing needed time at its minimum possible rate to complete the project under limited resources is achieved due to the implementation of the heuristic of minimum late start time as a single heuristic. - The second optimum solution is achieved due to the implementation of the heuristic of minimum late start time plus minimum total float time as a dual heuristic. - The third one is achieved due to the implementation of the heuristic of minimum total float time as a single heuristic. - The other heuristics are organized in a specific criteria according to their effect in optimum solution. - From above its clear that this study allowed the development of a new heuristic based on the research results and as applied to the Sudanese construction industry to optimizing scheduling of none repetitive projects. It was also possible to plan and control none repetitive projects through scheduling and time optimization while considering constrained resources, so the optimum balance between increasing need for minimum time to complete the project when the project is subjected to limited resources is achieved.