Swelling Characteristics of an Expansive Soil before and after Stabilization with Cement- By-Pass-Dust

Abstract

Abstract This paper investigates the swelling characteristics of an expansive soil before and after stabilization with cement-by-pass-dust (CBPD). The CBPD was added to the soil in varying proportions of 6, 9, 15, 20 and 30% of the dry weight of the soil. Both untreated and treated soils were subjected to various testing programs. The effect of the stabilizer on the engineering properties of the soil such as Atterberg limits, compaction, swelling, mineral composition and fabric were studied in details. The compacted untreated soil showed high swelling percent and swelling pressure. It was found that the liquid limit, plasticity index, shrinkage percent, swelling percent and swelling pressure decreased as the amount of CBPD increased and the optimum content of CBPD was 15% of the dry weight of the soil.. XRD and SEM results were used to explain the mechanism of the stabilization process. The time rate of swelling of treated soil follows similar trends to those of untreated soil, but with smaller maximum swelling percent.