Soil Stabilization Using Oil‐Shale Solid Waste

Abstract

Oil‐shale solid wastes are evaluated for use as soil stabilizers. A laboratory study consisted of the following tests on compacted samples of soil treated with water and spent oil shale: unconfined compressive strength, moisture‐density relationships, wet‐dry and freeze‐thaw durability, and resilient modulus. Significant increases in strength, durability, and resilient modulus were obtained by treating a silty sand with combusted western oil shale. Moderate increases in durability and resilient modulus were obtained by treating a highly plastic clay with combusted western oil shale. Solid waste from eastern oil shale appears to be feasible for soil stabilization only if limestone is added during combustion. Testing methods, results, and recommendations for mix design of spent shale‐stabilized pavement subgrades are presented and the mechanisms of spent‐shale cementation are discussed.