Engineering Properties of Foamed Recycled Glass as a Lightweight Fill

This paper presents the engineering properties of a lightweight-foamed glass aggregate (LWA-FG) for consideration as a lightweight fill material for use in retaining structure, embankment, highway, and bridge abutment construction in the United States. A laboratory study was conducted to evaluate the effect of compaction energy on the gradation, compression and direct shear strength of LWA-FG produced in the United States by Aero Aggregates, LLC. Dry and wet particle-size analyses were conducted before and after each of the engineering property tests to determine the amount of particle breakage due to the crushing effect of the impact and vibratory compaction, static compression, and/or direct shear testing. The results indicate the normally uniformly graded LWA-FG (as produced) transforms into an increasingly well graded material as a function of increasing compactive effort, static loading, and shear conditions. Therefore, the engineering properties of unit weight, compressibility, and shear strength of the LWA-FG are directly influenced by the amount of particle breakage and changes in particle distribution during processing. Useful laboratory test data for comparison to field observations and measured field performance are provided from this limited study.