New hybrid simulation model of urban construction waste management : an empirical study in Shenzhen, China

China faces a rapid urbanization in the present status quo. As a result, there is an exponential increment in construction waste generation. This has posed many environmental and social issues such as increase in illegal dumping sites. Construction waste management (CWM) therefore has become essential. However, urban CWM depends on various policies, laws, micro and macro factors. There is a clear lack of simulation model to explore the impacts of all these factors on CWM. This research study aims to propose a new hybrid simulation model to carry out an in-depth analysis on the urban CWM considering various sub-systems. The proposed hybrid simulation model integrates agent based modeling (ABM), system dynamics (SD) and discrete event simulation (DES). Lean construction (LC) theory is also considered for source reduction in waste generation. This research study obtained waste generation data from 51 newly built residential houses in Shenzhen in 2019. Afterwards, researchers developed the proposed hybrid model and longitudinally compared waste management from two different processes of lean construction and traditional construction under the benchmark policy. The environmental and treatment costs in five different types of simulation experiments (Benchmark policy, source sorting policy, specific charge policy, regulatory education policy and combined policy) are compared and analyzed horizontally. The simulation results show that the average landfill time of the lean construction waste treatment process is about 17% lower than that of the traditional construction. Further, the treatment cost saves about 374,000 yuan (approximately USD 56,100) and then generate the environmental benefits worth of 2.86 million yuan (approximately USD 0.429 million) additionally. The simulation results also show that compared to the benchmark policy, the combined policy increases the processing cost by 454,000 yuan (approximately USD 68,100) and creates environmental benefits worth of 5.80 million yuan (approximately USD 0.87 million). This study reveals the dynamic principle through hybrid simulation, which provides scientific guides for relevant management departments or enterprises to control CW, design corresponding control measures and reduce illegal dumping.