Quantitative effects of thickness and coarse-grained sand additive on soil cracking through crack parameters

Abstract

In this paper, an attempt was made to evaluate the effects of thickness and coarse-grained sand additive on cracking of Kaolinite clay using digital image processing (DIP). To minimize the errors which can occur in using DIP, control point selection (CPS) technique was applied. To determine the quantity of soil cracking, images of cracked soil after converting to binary were used to quantify crack parameters by automatically applying a written program. The measurements showed that the variation of most crack parameters is described as a power function of thickness with the high regression coefficient, more than 0.99, except area of fracture, by using the fitting curve method. In addition, the variations of length of cracks, width of cracks, area of cracks, number of pattern and number of fractures are inversely proportional while those of characteristic distance as well as mean cell area are directly proportional to the percentage of coarse-grained sand additive.