Soil Shrinkage Characterization of Low Plasticity Soil Using Digital Image Analysis Process

Document Type : Original Article


1 Department of Civil Engineering, National Institute of Technology, Warangal, India.

2 Civil Engineering Department, Associate Professor, National Institute of Technology- Warangal, warangal, 506004.

3 Department of Civil Engineering, Indian Institute of Technology, Madras, India


The goal of this paper is to better understand the shrinkage behavior of low plasticity (CL) soil, which is common in Warangal, India. Understanding the tensile strength and hydro-mechanical response of soil requires an understanding of the contraction behavior of soil caused by drying during wet-dry moisture cycles. With the use of simple and reliable experimental approaches, the shrinkage mechanism and behavior with suction variation are characterized and described in this study. The findings are related to the change in suction, water content, and void ratio of soil that has been air-dried from complete saturation to dryness. The proposed framework uses two simple approaches to understand soil water retention during the drying phase: one to quantify the suction potential and the other to characterize the shrinkage mechanism. In addition, the use of digital image processing (DIP) to capture sample shrinkage using a simple experimental setup is thoroughly discussed. ImageJ software has been found to be feasible for DIP and to quantify the volume change of laboratory samples. The absence of well-structured soil phases or macropores is attributable to the presence of only normal shrinkage and zero shrinkage phases in the tested soil. In terms of water–retention behavior, the shrinkage curve, and the suction curve are very similar. The effects of capillary suction on the shrinkage response of low plastic soil have been observed, emphasizing the importance of characterizing soil shrinkage behavior using suction as a stress-state variable in volume change studies.