The engineering problems of problematic soils are mainly related to their mechanical, physical, and mineralogical properties. Extensive efforts have been directed to mitigate damages that may happen for structures constructed on, or in these soils' types. Both conventional materials (e.g. cement, lime, etc.), chemical and produced materials were blended, mixed, or added to soils to improve their geotechnical properties. In the last years, different additives from the wastes of industrial processes have been adopted in engineering researches to improve soils. This paper reviews different industrial wastes materials (e.g., fly ash, blast slag, rice husk ash) as soil stabilizers, where the use of them has economic and engineering benefits. The effect of these materials on physical properties, compaction characteristics, compressive strength, and bearing ratio of soils have been presented, studied, and discussed. The contents of these materials are widely varied from reference to reference and reach a maximum value of 50%. These materials cause reduction in Atterberg limits and swelling potential to different degrees. For some soils, MDD and OMC increase with the addition of these materials, and verse versa. Almost, these materials cause an improvement in soils' strength and CBR. However, some wastes reveal more efficiently to improve the soil

Most of the soils suffered from significant geotechnical problems dependent on factors like the type of soil, soil composition and mineralogy. Specifically, the problems related to mechanical and physical properties of soils. Several studies have been used to mitigate the adverse effects of soils through using either additive conventional materials such as cement, lime or these soils blending with produced material and chemical materials. This paper focuses on stabilizing or improving different soils using sustainable materials. These materials provided environmental and economic benefits while mitigating a health hazard, storage problems, and a potential pollution source. They can be classified according to these sources into four groups: industrial waste (by-products), agriculture waste, domestic waste and mineral waste. According to the results of this review, compaction characteristics, California bearing ratio and unconfined compressive strength have been studied and discussed in this paper.

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.