Optimized flowshop scheduling for precast production considering process connection and blocking

Precast production scheduling is a key issue in prefabricated construction. Process connection and blocking are two characteristics of the flowshop production of precast components; however, they have received little attention in research on production scheduling, which may prevent actual production from following optimized scheduling schemes. In this study, an optimization model for the production scheduling of precast components was established considering process connection and blocking for minimizing the total penalty cost of earliness and tardiness. A solution for the model was designed and applied to a practical case for validation. The results indicate that the improved scheduling scheme can reduce the penalty cost and facilitate on-time delivery of precast components under two scenarios: tardiness partially allowed and no tardiness allowed. The proposed model and method can help precast plants to improve efficiency and reduce cost in addition to enhancing the practicality of precast production scheduling schemes.