Mathematical Model for Cost Evaluation of Lateritic Soil Treated with Bagasse Ash and Cement for Low-Cost Roads

Abstract

Frequent rise in the price of cement in Nigeria has prompted the search for other pozzolanic materials that could be used as supplement or partial replacement for economy. In addition to this is the use of locally available materials like lateritic soils for low-cost roads. However, in practical terms, the use of all these materials without proper cost benefit analysis could be misleading. Thus this study was an attempt to develop a mathematical model for cost evaluation. This was achieved by carrying out market survey and cost analysis for all the constituent materials (cement, bagasse ash, water and lateritic soil) in the mix to sum them up using a reference weight of 100 grams of dry soil for determining percentage requirements for all the constituent materials. The model was used to evaluate the cost of stabilizing with only cement (without bagasse ash) and a selected mix proportion that satisfied the requirements for sub-base of road work for the purpose of comparison. The cost for the selected mix was 42.85 kobo for stabilizing 100 grams of lateritic soil while that of stabilizing with only cement was 43.52 kobo which is of greater value of cost but of less quality.