Construction operation simulation reflecting workers' muscle fatigue

Discrete event simulation (DES) is widely regarded as an effective tool for modeling, analyzing and establishing the correct design of construction operations, including the proper quantity and sequencing of resources within the context of a selected field construction method. However, a gap exists in current construction operation studies with respect to human factors, specifically, workers' physical aspects. Construction workers, one of the most important resources in construction operation, have limited physical capabilities due to fatigue depending on individual- and task-related factors. However, less attention to fatigue has been paid in DES studies in construction, despite its significant impacts on construction performance. To understand dynamic impacts of workers' physical constraints on construction performance, we propose worker-oriented construction operation simulation integrating a fatigue model into discrete event simulation. Specifically, workers' activities during construction operations are modeled using DES in an elemental task level. Then, physical demands from the operation are estimated through biomechanical analysis on elemental tasks. Fatigue, which refers to diminished physical capabilities under given physical demands, is predicted using a fatigue model, and its impact is subsequently reflected in DES. As a preliminary study, we tested the feasibility of the proposed approach on masonry work by varying crew size. The results indicate that excessive physical demands beyond workers' capabilities result in productivity losses. Ultimately, the proposed approach has the potential to decide alternatives for construction operation planning to secure high productivity without compromising workers' health.