Hydraulic Conductivity and Drained Strength of Recycled Asphalt Pavement and Crushed Concrete.

摘要

Recycled asphalt pavement (RAP) and crushed concrete (CC) are potentially good fill materials for many highway construction projects. The Texas Department of Transportation is considering the suitability of using RAP and CC as backfill in the construction of mechanically stabilized earth (MSE) walls. This report focuses on the laboratory measurement of the geotechnical properties of these materials. Tests were conducted on 4-inch (100 mm) diameter triaxial specimens of compacted RAP and CC to measure the hydraulic conductivity and drained shear strength of each material. Comparison tests were also performed on a more conventional crushed limestone fill material. Based on these tests, RAP appears to exhibit adequate strength and hydraulic conductivity for use as an MSE wall backfill. However, additional tests are warranted to study possible creep strength loss in RAP. CC also exhibits adequate strength, but has a relatively low hydraulic conductivity. Additional tests are warranted to determine how the hydraulic conductivity of CC is affected by the finer fraction of this material.