Investigating the effect of applying maize cobs and husks ash with lime for stabilization of soil bases

Abstract

Soil stabilisation has become a major issue in construction engineering and the common soil stabilising techniques are becoming costly day by day due to the increasing cost of the most widely used stabilizing agents such as cement, lime, bitumen, etc. Regardful of the afore mentioned statement, research studies concerning the effectiveness of using industrial wastes are rapidly increasing and some of the materials tested have proved to be effective, Fly Ash and Rice Husks Ash being examples of such materials. Most of these materials have been coupled together with Cement and Lime for their full effectiveness in stabilisation and this, has not only improved waste management, but has also reduced costs incurred during stabilisation. This research study precisely investigated the suitability and effectiveness of the locally available Maize cobs and Husks as a material to be used for soil stabilisation. It involved obtaining two soil samples i.e. a coarse and fine aggregated sample, incinerating of maize cobs and husks to get the finer ash, then stabilising the soil samples using an optimum percentage of lime i.e. 4% coupled with varying percentages of Maize Cobs and Husks Ash i.e. 2%, 4% and 6%. Observations were made for the effects and changes in the following index and engineering properties of the soil samples; Maximum Dry Density, Optimum Moisture Content, California Bearing Ratio, and Atterberg Limits tests. The general summary of the findings deduced that addition of Maize cobs and Husks Ash with Lime to the soil samples increases the MDD, decreases the OMC, increases the CBR, and reduces the PI. 4% Ash yielded the best results for CBR of both soil samples, 2% Ash and 4% Ash yielded the best results for MDD and the relative OMC of the fine aggregate and coarse aggregate respectively, and 2% Ash and 4% Ash yielded the best results for the PI of the coarse aggregate and fine aggregate respectively.