Simulating the Long-Term Performance of Multifunctional Green-Pervious Concrete Pavement in Stormwater Runoff-Induced PAHs Remediation

摘要

Stormwater runoff-induced polycyclic aromatic hydrocarbons (PAHs) increasingly raise concerns about groundwater quality and safety. Among stormwater management infrastructures and facilities, pavement plays an important role as the frontier of water protection. To remodel or reconstruct the current aging infrastructure, innovative construction materials with sustainable development capabilities are highly in demand. Recently, a multifunctional green-pervious concrete (MGPC), which is an organoclay-amended pervious concrete, has been proven to serve as a next generation pavement material at the lab scale. To simulate the long-term performance of MGPC, an ideal site under steady-state groundwater conditions was built up by using the finite-element method (FEM). Lab experiments were conducted to determine the adsorption function, diffusion coefficient, and other physicochemical parameters of the proposed MGPC. Three sorption isotherm models (linear, Freundlich, and Langmuir) were fitted to the sorption test data. FEM was used to analyze the PAHs removal by passing through the MGPC pavement and PAHs transport in the soil stratum under different scenarios. The simulation results revealed that the MGPC had a significant remediation efficiency on the PAHs. Other than the material properties of MGPC, the efficiency of contaminant remediation of MGPC was also influenced by the permeability of the subbase and the initial concentrations of PAHs. It was also found that the linear isotherm model would overestimate the removal efficiency of PAHs under higher concentration source (100 mg/L).