Composite Stabilization and Model Prediction of Geotechnical Parameters of Lateritic Soils within the Coastal Plains of Akwa Ibom State, Nigeria

Composite soil stabilization involves addition of two or more modifiers such as river sand and inorganic chemical such as cement to lateritic soil. This measure has a dual effect on the behavior of the soil structure. River sand provides volume stability while the inorganic chemical accelerates chemical bonding and ensures reduction of permeability. The soil structure increases in strength, durability as well as a reduction in deformability. To improve the engineering qualities of natural soil, composite soil stabilization relies on treating it to both physical and chemical treatments. Ideally stabilization of weak soil has a basic objective. It is to find the most efficient and economical method so that the properties of a relatively weak soil are improved to withstand any imposed or shearing stresses. The main objective here is to examine the changes and particulate system distribution of coastal lateritic soil and stress response to imposed mechanical systems as well as contact behavior on application of various stabilizers. The most common purpose of soil treatment is to improve shear strength and loading capacity, as well as stability and settlement control.

Calcium is the most important component for soil stabilization in all instances. In addition to plasticity reduction, Portland cement, by its inherent nature of producing strength – developing hydration products, provides improved strength and durability. As a result, the effectiveness of stabilization is based on the number of positions of exchangeable ions – mineralogical composition which is related to liquid limit and the amount of liberated calcium ions from cement [% of cement, % of compaction and curing time] which influences the durability [bonding effect] and unconfined compressive strength [bearing capacity]. The lateritic soil formation within the area under investigation is predominantly dilatant in nature. In order to deploy this material for construction purpose adequate [composite] treatment is required. Additionally, stone base as a feature of design by practitioners has assumed alarming proportion. This has increased the cost of construction to a very high pedestal. This research is designed to investigate the origin of this dilatant laterization and to verify viable but economic means of treatment [stabilization] to reduce to barest minimum the escalating cost of modifying this material for deployment in engineering and construction operations. It is very crucial as it will provide an in-depth knowledge of some engineering properties of lateritic soils within the coastal plains of Akwa Ibom State.