Strength Characteristics of Crushed Concrete and Carbide Wastes Stabilization of Clayey Soil as Highway Material

Abstract

The functionality of a highway pavement is often judged by the quality and engineering properties of the soil-pavement structures and the materials used to improve the properties of these underlying soils. In this study, crushed concrete waste and carbide waste, whose associated disposal problems constitute environmental hazard, were used for the stabilization of clayey soil using British Standard heavy (Modified Proctor) compaction energy, and used as highway construction material. The various mixes were subjected to particles size analyses, specific gravity, moisture content, Atterberg limits, compaction characteristics, California bearing ratio, unconfined compressive strength test triaxial and water absorption tests. The test results show that the properties of the clayey soil improved with its stabilization with crushed concrete and carbide wastes. The maximum dry density decreased from 1.93 to 1.29 Mg/m3 with corresponding increase in optimum moisture content from 6.0 to 16.6 %, as carbide waste content increased, and crushed concrete waste and clayey soil contents of the mixtures decreased. The maximum California bearing ratio value of 55.01 % (unsoaked and soaked for 24 h) recorded for 25%CS + 75% (75%CCW + 25%CW) mix can be used as subbase material in flexible pavement construction. Further work may assess resilient modulus of this material under cyclic load.