Study On Rupture Characteristics Of Malan Loess By Triaxial Tension Test

The tensile strength of the soil is smaller than the shear and compressive strength,mechanical properties of soil under tensile state is often ignored by people, but in dam corewall, tensile huge buildings, ground fissures and landslide trailing edge cracks caused bysome geotechnical engineering problems, such as people on the tensile strength ability putforward higher requirements. This article is based on a series of transformation ofconventional triaxial apparatus, made to the stele tableland landslide of undisturbed loess andremolding with different confining pressure, moisture content and dry density by consolidatedundrained tests, to obtain tensile strength parameters. Based on the experimental results, underdifferent confining pressure and moisture content of the relationship between tensile stressand strain are analyzed, and the tensile strength as the confining pressure and moisture contentchange curve, tensile strength parameters, so as to optimize the loess slump materialparameter selection of calculation model.The triaxial tensile test of undisturbed loess indicates that the moisture content andconfining pressure has significant effects on undisturbed loess triaxial tensile strength. Withthe increase of water content, the triaxial tensile strength of loess decreases; confiningpressure increases, the triaxial tensile strength of loess are also gradually decreases, andsatisfy the linear regressive relationship between the two. And when the confining pressureincreases to a certain value, the axial stress by the tensile stress to compressive stress, andwith the increase of confining pressure, fracture when the compressive stress will alsoincreases.The triaxial tensile test of remolding loess showed that the tensile strength of the soil andthe confining pressure, moisture content and dry density is close. With the increase ofmoisture content, tensile strength significantly reduced; And dry density increased, tensilestrength increase. With the increase of confining pressure, reshape the loess increase tensilestrength, tensile strain increase, the fracture of the axial stress from the tensile stress tocompressive stress. The characteristics of the loess in the triaxial tensile test study shows that the confiningpressure, moisture content and dry density are the important factors influencing the triaxialtensile fracture characteristics, the loess plateau area in the engineering construction shouldfully consider the three influence on tensile properties.