An environmental assessment and optimization method for contractors

Construction-related environmental impacts have increased with the rapid urbanization in China. Contractors could mitigate the environmental impacts of a building's construction phase by developing an environmentally-friendly construction scheme. However, a construction scheme that performs well on one environmental metric may perform poorly on others. Moreover, it becomes challenging to select the best plan when various construction schemes and diverse environmental metrics need to be considered. This research explores how a multi-objective optimization method can provide Pareto optimal solutions that will help the contractor select a construction scheme that performs well on all environmental metrics. A quantitative environmental assessment and optimization method (EAOM) was established to evaluate and optimize the construction environmental performance using a combination of Life Cycle Assessment (LCA) and Particle Swarm Optimization (PSO). Assessment and optimization were implemented as two integrated and interactively functional modules to complement LCA in multi-objective decision support. In a case of reinforced concrete project, EAOM generated four Pareto construction schemes within 864 possible solutions in a remarkably short time. The results indicate that EAOM is an effective and efficient decision support tool that contractors can implement to improve the environmental performance of construction processes.