Performance of Expanded Clay Shale (ECS) as an Embankment Backfill

Light weight aggregates (LWA) have been extensively used throughout North America for more than 80 years in cast-in-place structural lightweight concretes for high-rise buildings and bridges. They are now being used for several geotechnical applications including as a backfill in the embankment laid over soft soils, or as a fill material in the retaining wall structures. A research study currently focuses on the use of LWA derived from the manufacturing of Expanded Clay Shale (ECS) as an embankment fill material along State Highway (SH) 360 in Arlington, Texas. This paper first presents the laboratory results obtained by testing Expanded Clay Shale (ECS) material to evaluate its function as embankment backfill. Both direct shear and consolidation tests were performed to evaluate its strength characteristics. This embankment was instrumented with vertical inclinometers to monitor fill movements. Based on the monitored data, it can be mentioned that the use of ECS resulted in less settlements of embankment at the site.