BCD: A New Instrument for Compaction Control

摘要

The BCD (Briaud Compaction Device) is a tool that can be used to control compaction quality for pavement subgrade, pavement bases, pavement sub-bases, embankments, retaining wall backfill, and any other earth work requiring compaction. The BCD is a very rapid tester of the soil modulus near the ground surface. It has a 150 mm diameter flexible plate at the bottom end of a rod. The operator leans on the handle at the top end of the rod, the plate bends, the bending strains are instantaneously measured by strain gages on the bottom plate. If the soil is hard, the plate does not bend very much, if the soil is soft, the plate bends more. It is shown that the strain measurements are directly related to the modulus of the soil underneath it. In this report the design improvements of the previous prototype BCD are described. The finished product is BCD-4; it is built by Roctest who also sells the BCD under a licensing agreement with Texas A&M University. Numerical simulations were performed to evaluate the depth of influence of the BCD in the field and in the lab.