Optimizing individual resource assignment using genetic algorithm

Abstract

Construction activities are mostly determined by the technique known as critical path method (CPM) based on technical relationships and by resource allocation techniques which is used to examine daily resource requirement. These resource allocation techniques analyze the overall resource profile of a project without considering working timetable of any individual resource. Generally, in practice, an assigned foreman designated by a project manager will be responsible for assigning resources to a particular activity. Most of the time, this assignment is done when an activity is about to start. Therefore, working timetables of an individual resource cannot be known in advance. Although most foremen can allocate resources at low cost, there are many occasions that workers are forced to be idle between jobs or to suddenly change to different tasks. These could result in inefficiency as they affect workers’ income and their learning process. This paper proposes the use of genetic algorithm technique to assist in the search for a work plan resulting in the most cost-effective working timetable of an individual resource in a construction project with unlimited resources. In this study, the efficiency is measured in three dimensions including: the number of releases and re-hires, the number of resource idle days and the total number of resources required. To identify the most cost-effective schedule, five different schedules of a project example were generated. They are 1) early start schedule 2) late start schedule 3) min Mx schedule 4) min RRH schedule and 5) min RID schedule. Then the respective resource allocations are compared. The results show that, in the case that idle days were considered unpaid days, the Mx schedule delivered the lowest cost as well as the lowest number of resource requirement. In the case that resources were paid on idle days, the RID schedule was found to incur the lowest cost while RRH & RID schedules required the least number of total resources. Based on the study’s findings, it is recommended that, schedule analysis should be carried out with the planning of the individual resource timetable to be able to manage project resource efficiently and cost-effectively.