Laboratory investigations on stabilization of weak clay soil using rice husk ash and cement

Abstract

Soil acts as a foundation for the pavement and significantly impacts the long-term performance. With the incessant construction of the pavements, the availability of soil with desired engineering characteristics has become questionable. In this regard, stabilization has been considered one of the engineering measures to improve the soil characteristics. Conventionally, cement, lime, fly ash, bitumen, etc., have been used extensively as soil stabilizers. However, recent studies are focusing on utilizing stabilizers, which can reduce the carbon footprint of pavements. Rice husk ash (RHA) is one such agricultural waste that can stabilize the soil. The main objective of this study is to investigate the potential of RHA as soil stabilizers, considering the strength and durability aspects. In this study, locally available clay soil was stabilized with different contents of RHA and RHA + cement. Based on the strength and stress�strain characteristics, it was found that 9.0% RHA was found to be optimum. However, durability tests showed that RHA alone could not improve the durability of soil. Considering 9% RHA, 3, 6, and 9% cement was added to enhance the soil characteristics. The addition of RHA + cement improved the soil characteristics better than cement alone. The addition of optimum RHA was able to reduce the cement content by at least 1.0%, which is an economical and sustainable solution. Simple linear regression models were developed to predict the modulus of soil stabilized with RHA and RHA + cement with strength. � 2022, Springer Nature Switzerland AG.