Weak tensile characteristics of loess in China--An important reason for ground fissures

摘要

By means of uniaxial tensile tests, we analyzed the tensile characteristics of undisturbed and disturbed loess samples taken from the areas where ground fissures are prevalent. The study shows that the tensile strength and ultimate tensile strain of loess are very small, no more than 25 kPa and 0.5%, respectively. Water content and dry density are the two important factors for the tensile strength of loess, and show a decreasing exponential and increasing exponential relationship with the tensile strength, respectively. From the results of tensile tests on loess and the mechanism of ground fissure development in loess areas, we may draw a conclusion that the weak tensile strength, the loose structure and the collapsibility are the important contributing factors to the development of ground fissures in China's loess areas.