Development of a hybrid method of social force modeling and discrete event simulation to optimize productivity of construction

Optimizing productivity of construction has always been a challenge for project managers and planners. In previous studies, it has been pointed out that productivity is directly related to the number of workers unless the excessive number of workers in the workshop causes congestion. Discrete event simulation is one of the mathematical modeling methods used by researchers to study productivity in construction. Discrete event simulation models the operations considering the flow of resources and the state of entities within the system. In this model, the entities are passive elements that are processed during the work process. Due to the nature of the entities in a discrete event simulation model, it is not possible to investigate the effect of physical interaction of individuals on productivity using this method alone. Social Force Modeling has a great ability to model the movement of people and physical interaction between people and the environment. This study tries to investigate the direct impact of manpower on productivity by modeling the work process and the effect of physical interactions of workers due to the increase in the number of workers and workshop spatial constraints. For this purpose, a hybrid model has been developed that includes a combination of two models. In the first model, the discrete event simulation method is used to simulate the work process. In the second model, the movement and physical interaction of workers are modeled using the social force modeling method. The proposed hybrid model allows one or more activities to be simulated more accurately. The approach used in this paper is evaluated based on the data from a real project. The results clearly show the reduction in productivity due to overcrowding. The outputs of this work can be used to obtain the optimal number of workers in an activity. The model proposed in this paper gives project managers the chance to have more realistic simulations of work processes.