Examination of Policies to Achieve Sustainable Concrete Waste Recycling: The System Dynamics Modelling Approach

Concrete waste is crucial to the environment, and its recycling is encouraged to minimise the environmental impacts. This study aims to examine various policies to achieve sustainable concrete waste recycling in Thailand. The system dynamics modelling approach is used to capture dynamic changes of the concrete waste recycling process and assess the environmental impacts of concrete waste from townhouse demolition and the recycling process in Bangkok, Thailand. The results show that the impacts of energy consumption and CO 2eq emission, which are global impacts, are the most severe and evident in the concrete waste transportation process, contributing to 40% of the total amount, which is expected to be 0.5 million kgoe and 1.1 million kgCO 2eq in the next 20 years. Increasing the truck capacity reduces energy consumption from fewer trips, resulting in less CO 2eq emission. Transferring to electric trucks for transportation and demolition robots for demolition may assist in reducing energy consumption and CO 2 emissions by 40% (about 0.2 million kgoe and 0.4 million kgCo 2eq reduced) compared with current practices. The results also revealed that concrete waste recycling can improve material and landfill savings impacts. Increasing the plant’s capacity increases material savings and reduces landfill consumption. The results provide guidelines for the construction industry, policy makers, and academics to support the national net-zero, energy efficiency, and waste management targets by considering dynamic changes rarely mentioned in previous studies.