Using VSM Method and DES Modeling for Optimizing Concrete Flooring Process of Industrial Buildings

In recent years, the use of lean construction has been expanded to reduce waste and increase productivity in construction projects. Construction managers and engineers try to use innovative methods to reduce waste in construction projects. There are repetitive processes in construction in which waste can be avoided by reducing lag time. This research aims to optimize construction processes using the Value Stream Mapping (VSM) method. For this purpose, the process of Industrial Concrete Flooring (ICF) was selected as one of the sub-constructions of industrial buildings. First, the ICF process was mapped using field observations and recording the time of each activity. Second, the process was modeled using Discrete Event Simulation (DES). The DES model was improved after identifying the process’s bottleneck through the analysis of the developed model. The analysis showed that concrete leveling activity acts as a process bottleneck leading to an increase in the duration of the concrete remaining (about 51 min) in the truck mixer and a reduction in the productivity of workers and machinery. Finally, the developed model was modified. As a result, the duration of concrete remaining in the mixer was reduced to 18 minutes, and the utilization of labor and machinery was also improved.