黄土拉张破裂特性试验研究

Experimental research on tensile fracture characteristics of loess

通过单轴拉伸试验,分析了地裂缝发育区原状黄土与重塑黄土的拉张破裂特性。研究表明,黄土的抗拉强度及极限拉应变均很小,抗拉强度一般仅有几到十几kPa,极限拉应变仅千分之几;含水率与干密度是影响黄土抗拉强度的两个重要因素,它们与抗拉强度之间分别满足递减的负指数关系与递增的指数关系。因此,黄土本身的弱抗拉特性是导致黄土地区地裂缝等地质灾害较为发育的一个重要因素。

Through uniaxial tensile tests, the tensile fracture characteristics of undisturbed loess and remolding loess in the zone with developed ground fissures are analyzed. The study shows that the tensile strength and ultimate tensile strain of loess are very small, which are often several or tens of kPa and several in a thousand respectively. The moisture content and dry density are the two important factors for the tensile strength of loess, and they have decreasing exponential relationship and increasing exponential relationship with the tensile strength of loess. Therefore, the weak tensile characteristic is an important factor for the development of geo-hazards like ground fissures developed in loess areas.