Development of a Crew Allocation-Based Simulation Optimisation Model to Improve Off-Site Pre-Cast Concrete Production Operations

The increased use of precast components in construction projects has led to the introduction of innovative management and scheduling systems to improve reliability, efficiency and cost of off-site pre-cast production operations. The aim of this study is to develop an innovative crew allocation system that can efficiently allocate crews of workers to labour-driven processes in the off-site pre-cast production operations. As part of the methodologies used in developing the Crew Allocation System, a visual modelling technique is used to capture and understand the hierarchal relationships in the production processes. Discrete Event Simulation Methodology is adopted to convert the developed static visual model into a dynamic one. ARENA Rockwell software is used to develop the production processes simulation model. Genetic Algorithms are embedded within the simulation model to provide a rapid and intelligent search. A Multi-Layered chromosome concept is used to store different sets of inputs such as crews working on different shifts and their skills. One of the sleeper’s precast concrete manufacturing systems is chosen as a test bed for the proposed concept. Results will expect to show that adoption of different combinations of crews of workers will have a substantial impact on the labour allocation cost and throughput time.