CLASSICAL OPTIMIZATION OF BAGASSE ASH CONTENT IN CEMENT-STABILIZED LATERITIC SOIL

Abstract

Optimization of construction materials with laboratory data is a very possible way of minimizing waste of resources (materials and cost). There had been several successful attempts of optimization of construction materials. However, optimization in soil stabilization for road-work has been very rare because of its complexities. Compaction, California bearing ratio, unconfined compressive strength and durability tests were carried out on cement-stabilized soil. Constant cement contents of 2%, 4%, 6% and 8% with variations of bagasse ash from 0% to 20% at 2% intervals and all percentages used were by the weight of dry soil. The classical method was applied in this work to optimize the amount of bagasse ash content in cement-stabilized lateritic soil. Geometric models that govern the relationships of cost of bagasse ash content, cement content, optimum moisture content and strength characteristics of the stabilized-soil matrix were used to develop non-linear programming model. Then it was linearized and solved using the simplex method with sensitivity analysis. The optimal solution at the desired unconfined compressive strength and California bearing ratio for sub-base of road-work for bagasse ash content, cement content and optimum moisture content were found to be 14.03%, 4.52% and 22.46% respectively. Optimzation and the use of bagasse ash gave a cost benefit of 9.24% with a better mix. The classical optimization technique appears to be suitable in soil stabilization. http://dx.doi.org/10.4314/njt.v35i3.3