Compaction characteristics of natural cohesive subgrade soil stabilized with local sustainable materials

Abstract

In traditional road construction, the most common source materials for roadbed layers are the borrow pits. During the construction process, the source’s materials, excavation, loading, and handling have been considered significant factors on total construction cost. Improving the geotechnical properties of the locally available source materials using the waste materials of the local industry (as additives) is helped in avoiding undesirable additional costs in the field construction. The present paper explains the results of an experimental study of compaction characteristics for subgrade material of districts of Baghdad, Iraq with two different types of local byproduct materials “cement dust and fly ash materials,”. The selected soil, cement dust, and fly ash mixtures were made ready for use in the laboratory, and the mixtures’ compaction properties were investigated. Both light and heavy manual compaction tests were carried out and compared. The effect of selected stabilizers on the compaction behavior of the subgrade soil was determined to obtain the optimal values of stabilizer materials. The finding of this paper indicates that the compaction characteristics and behavior of the subgrade soil greatly depend on the type of additives used. However, the subgrade stabilization with local byproduct materials is beneficial from economic and environmental points of view.