Enhancing the engineering properties of expansive soil using bagasse ash and hydrated lime

Abstract

The main objective of this paper is to investigate the influence of hydrated lime and bagasse ash on engineering properties of expansive soil obtained from an array of laboratory tests. Bagasse ash is a readily available waste by-product of the sugar-cane refining industry posing risks to environment. Bagasse ash is considered in this investigation in order to evaluate the potential benefits of its pozzolanic material for stabilisation of expansive soil. The preparation of stabilised soil specimens was conducted by changing the bagasse ash contents from 0 to 25% by dry weight of expansive soil along with an increase in hydrated lime. The bearing capacity and shrinkage properties of stabilised expansive soil were examined through a series of experimental tests including linear shrinkage and California bearing ratio (CBR) after various curing periods of 3, 7 and 28 days. The results reveal that the additions of hydrated lime and bagasse ash improved the strength and bearing capacity of stabilised expansive soil remarkably, and meanwhile significantly reduced the linear shrinkage of treated expansive soil. Hence, the application of hydrated lime and bagasse ash as reinforcing material can not only enhance the engineering properties of expansive soil, but also facilitate sustainable development by using sugarcane waste by-product to improve unusable clay material in road construction.