In construction engineering, project schedules are commonly established by the critical path method. Nevertheless, these schedules often lead to substantial fluctuations in the resource profile that are not only impractical but also costly for the contractors to execute. Therefore, in order to smooth out the resource profile, construction managers need to perform resource-leveling procedures. This paper proposes a novel approach for resource leveling, named as resource leveling based on differential evolution (RLDE). The performance of the RLDE is compared to that of Microsoft Project software, the genetic algorithm, and the particle swarm optimization algorithm. Experiments have proved that the newly developed method can deliver the most desirable resource-leveling result. Thus, the RLDE is an effective method and it can be a useful tool for assisting managers/planners in the field of project management. 1. Introduction In today’s market condition, the survivability of any construction contractor essentially depends on its capability of managing resources. Ineffective resource management escalates the operational expense or even gives rise to financial and scheduling problems [1, 2]. Without doubt, the excess requirement of resources in the construction site leads to the extension of project duration. As the construction contractor fails to deliver the project by the prespecified date, the owner may suffer from financial losses due to the nonavailability of the facility [3]. In addition, construction delays often bring about legal disputes among parties, higher overhead costs, and degraded reputation, and they occasionally result in project failures [4, 5]. As a consequence, resource management is an essential task that needs to be implemented thoroughly in the planning phase. Basically, resources in construction projects consist of manpower, equipment, materials, money, and expertise. Needless to say, the proper management of these resources holds the key to the successful accomplishment of any project [3]. However, construction schedules, generated by network scheduling techniques, are often characterized by undesirable resource fluctuations that are impractical and costly for the contractors to implement [6]. The reason is that it is expensive to hire and to lay off workers on a short-term basis according to the fluctuations in the resource profile. Additionally, if the resources cannot be managed efficiently, they may exceed the supply capability of the contractor and lead to schedule delay. Finally, the contractor must maintain a number of idle
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