冻结黄土抗拉强度的试验研究

Tensile Strength of Frozen Saturated Loess

冻结饱水黄土的拉伸试验表明，拉伸破坏均属脆性破坏类型，拉断面上矿物颗粒剪移错粒，裂隙发育。拉伸的应力－应变过程，视荷载作用的快慢大致可分为粘弹－塑性、粘－弹性和脆性破坏三类，它们可用统一的方程形式加以描述。此外，对饱水冻结黄土的峰值应力、破坏应变和破坏时间等特性进行了分析．对抗拉、抗压强度作分析比较后指出，它们的比值为０．４４－０．６３，与负温和加载速率的关系不大。

Tensile tests on the frozen saturated loess show that their failure is brittle. Shear and displacement of the mineral grain occur and mini-fissures grow on the cross section of the crack. The stress-strain processes of the tensile are classified into three types depending on the load rates i.e.viscoelastic-plastic, viscoelastic and brittle deformation. They may be described by an unitized expression. The features of stress-strain, peak stress, strain and time to failure of frozen saturated loess are also discussed in this paper. The ratio of tensile strength to compressive strength is 0.44-0.63 independently of the temperature and load rate.