In situ mechanistic characterisations of granular pavement foundation layers

Abstract

This paper presents experimental test results comparing in situ point test measurements using falling weight deflectometer (FWD), light weight deflectometer (LWD), dynamic cone penetrometer and static piezocone, and near continuous roller-integrated continuous compaction control measurements on a granular pavement foundation embankment. Piezoelectric earth pressure cells buried in the pavement foundation layers were used to compare vertical and horizontal stresses during vibratory roller compaction, and LWD and FWD impulse loading. The resulting total stress paths are compared with standard laboratory resilient modulus stress paths. Insights into differences in measurement influence depths and comparison of vertical stress profiles for the different measurements are discussed and relationships between the various measurements in terms of elastic modulus are presented. Some practical considerations for interpreting the relationships and implementation are discussed.