高应力下接触面抗剪特性影响因素分析

通过在DRS 1型微机高压直残剪试验系统上所进行的建筑砂、标准砂、粉土和粘土与砼、金属光滑、金属粗糙界面的正交直接剪切试验研究表明 :高应力作用下土体与刚度较大的界面的剪切应力 剪切位移曲线呈现出应变硬化的特征 ,与低应力作用下土与不同结构剪切特性存在明显的区别 .根据试验数据的方差分析和直观分析结果 :对于残余强度 ,法向应力的大小是第一影响因素 ,其次是土体的性质 ,第三是界面的基底性质 ,剪切速率的影响最小 ;对于剪切应力 -剪切位移曲线起始切线斜率 ,法向应力的大小、土体的性质是主要影响因素 ,第三是界面的基底性质 ,剪切速率的影响最小 .总的来看 ,影响高应力下接触面抗剪特性的主要影响因素是法向应力的大小 ,土体的性质是其次 ,剪切速率和基底性质的影响可以不予考虑 .

The affecting factors analysis on the shearing characteristic of the interface under high pressure

The orthogonal direct shearing experiments about building sand, standard sand, silt and clay on concrete interface, smooth and rough interface of the metals, using DSR 1 type computer high pressure shear system, have been conducted in the paper. The result show that the curve of shearing stress versus shearing displacement between soil mass and the interface with larger rigidity under high pressure presents strain hardening characteristic, which is obviously different from the shearing properties between soil and various structures under low pressure. According to the variance analysis and visual analysis of test data, the sequence of the factors affecting the residual strength is respectively as followings: normal stress, soil property, base and shearing rate; and yet the sequence of the factors affecting original tangential slope of shearing stress versus shearing displacement curve is the same. Summarily, normal stress is the main influential factor on the shearing characteristic of the interface under high pressure and soil properties are the second and the effect of base properties and shearing rate can be neglected.