Effects of Some Factors on the Strength and Stiffness of Crushed Concrete Aggregate

Abstract

A series of consolidated drained triaxial compression (TC) tests were performed on a crushed concrete aggregate (CCA) compacted using three different levels of energy. A wide range of moulding water content, w, and two different confining pressures were employed. The compressive strength and stiffness of the tested CCA when highly compacted at water content close or slightly higher than the optimum value, wopt, were very high, higher than those of a typical natural well-graded gravelly soil having similar grading characteristics used as the backfill material of highest quality. The compressive strength and stiffness of the tested CCA was not highly sensitive to changes in w, in particular when w ≥ wopt, but it decreased sharply when w became lower than wopt. The strength and stiffness was very sensitive to compaction energy, therefore the degree of compaction. All the test results show that highly compacted CCA can be used as the backfill material for important civil engineering soil structures, such as retaining walls and bridge abutments, that need a high stability while allowing limited deformation.KeywordsCompressive StrengthTriaxial CompressionRecycle Concrete AggregateParticle BreakageOptimum Water ContentThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.