Lightweight Cellular Concrete (LCC) for Stormwater Management in Parking Lots: A Design Optimization Approach

Lightweight cellular concrete (LCC) can substitute the thick aggregate layers within permeable parking (PP) lots. Nevertheless, LCC's lightweight may cause buoyancy forces that damage the PP lots. Increasing LCC density reduces buoyancy forces, adversely affecting PP lots' permeability and runoff storage capacity. Thus, this study assesses LCC feasibility in PPs and its influencing factors. First, the study conducted lab testing to develop various porous concrete and LCC materials with adequate strength while complementing permeability. Later, this study developed an optimization model that maximizes using LCC materials while avoiding buoyancy and meeting the required runoff storage capacity. Finally, this study demonstrated designing permeable parking lots for various rainfall intensities utilizing the lab-developed LCC materials and optimization model. Results indicate that combining aggregate and LCC layers is beneficial, with LCC reducing the thickness of aggregate layers by 75%-85%. The key factors affecting PP lots' hydraulic performance are the LCC density and void ratio.