Determination of soil–water characteristic curves by using a polymer tensiometer

Abstract

Recently, rainfall-induced slope failure has struck Cimanggung village, West Java province, Indonesia. In order to anticipate future slope failures due to rainfall, an unsaturated slope stability analysis is compulsory. Precise information on the soil–water characteristic curve (SWCC) is required to conduct an accurate unsaturated soil analysis. In this article, a procedure to obtain SWCC by using a polymer tensiometer for Cimanggung village is proposed. Considering the long period of time needed to obtain the measured data, some prediction methods are available. The measured SWCCs are then compared with SWCCs based on two prediction methods. Chin’s 1-point and Perera et al.’s methods are applied as the prediction methods and then compared with the measured SWCCs. It could be concluded that Chin’s 1-point method yields a close estimation within the suction range. Meanwhile, the Perera et al. method underestimates the air entry value, and the predicted curve deviates significantly with the measured SWCC. Hence, Chin’s 1-point method is recommended for predicting SWCCs in Cimanggung Village.

Keywords

• polymer tensiometer
• unsaturated soil
• suction measurement
• swcc
• cimanggung