Preliminary Examination of Hydraulic and Environmental Properties of Ultra-Lightweight Foamed Glass Aggregate

Ultra-lightweight foamed glass aggregate (UL- FGA or FGA) has been broadly used in the United States in geotechnical applications as a lightweight fill to raise grades over soft soils or near-sensitive structures. Produced from post-consumer recycled bottle glass, UL-FGA has a high porosity and a non-reactive elemental composition that may also make it an ideal candidate for use in stormwater infrastructure. Mechanical properties of the aggregate have been evaluated through geotechnical laboratory work, and case studies have confirmed the long-term performance; however, limited information is available regarding water flow and storage properties for use in stormwater applications. This study aimed to evaluate the hydraulic and environmental properties of UL-FGA through laboratory-scale physical models. The water storage capacity and infiltration properties as well as how these may change over multiple events, at different compaction levels, or in different engineered systems, were evaluated in addition to any possible impacts on water quality. Results indicated that FGA drains rapidly, has a high capacity for water storage, and has a minimal impact on effluent pH and electrical conductivity. Production and transport of fine particles and related geotextile compatibility should be investigated further in future research.