Lightweight Deflectometer Testing of Foamed Glass Aggregate

This paper describes a field-testing program consisting of 14 lightweight deflectometer (LWD) tests performed on compacted foamed glass aggregate (FGA) fill. The details of the LWD testing procedures and data interpretation are provided. A portion of the tests included either a 1.9 kPa (40 psf) or 7.2 kPa (150 psf) surface pressure to simulate the confinement provided by soil or crushed stone typically placed between the FGA and the pavement or floor slab. The results of the LWD tests are compared to static plate load (SPL) tests performed at the same locations under the same conditions. The dynamic modulus values, Edyn, interpreted from the LWD tests are compared to the second loading strain modulus values, E2, and second loading modulus of subgrade reaction, ku2, interpreted from the SPL tests. The results from this study show that Edyn generally increases with the magnitude of surface pressure. The results also show weak correlation between Edyn and E2 and some positive correlation between Edyn and ku2.