Evaluation of the use of tiles waste in stabilization of subgrade layer with rice husk ash as an activator agent

Abstract

Good design of highway gives a crucial contribution to economic growth and social benefit by providing access to employment, health and education services. In the process of designing the highway, the importance of having natural soil as subgrade layer is crucial to ensure the quality of road itself. One of the primary and major processes in the construction of highway is subgrade soil stabilization. Waste generation is increasing year by year due to the large amount of waste produced in Malaysia. That included tile waste (TW) and rice husk ash (RHA). The disposal of TW and RHA is currently a major problem in Malaysia in which it can be effectively used for soil stabilization. One of the attempt in this study is to make use of TW as an additive and RHA as an activator to stabilize clayey soil whereby this type of soil will have low bearing capacity which it is generally swell when in contact with moisture and shrink when the moisture squeezes out. Other than stabilization, many studies was conducted with the aim of reducing the cost for soil stabilization by means of using TW and RHA as the world is now facing a serious problem on handling disposal materials. The main aim of this study is to determine the optimum percentage of TW content with 10% of RHA as an activator agent in stabilization of problematic soil with low bearing capacity in the area of Batu Kawan, Pulau Pinang. It was found that soil was stabilized with five proportions of TW (15%, 20%, 25%, 30% and 35%) and constant RHA of 10% was used as an activator agent. The specimens were then cured for 0, 7 and 14 days before being subjected to the unconfined compression test (UCT). It was found that the optimum percentage of TW is at 30% added with RHA of 10% in soil. The highest value of UCT test for the particular sample was found to be 250.6 kN/m2. Therefore, the test results showed that the TW-RHA admixture could effectively improve the strength of problematic soil.