加筋土筋土界面抗剪强度影响因素试验研究

Experimental Study on Influence Factors of Shear Strength between Geogrid and Soil Interface

通过室内筋土界面直剪试验,考虑筋土界面抗剪强度的影响因素,进行了不同剪切速度、筋材空隙率及土体含水率下筋土界面直剪试验,分析了不同因素对筋土界面抗剪强度的影响。试验结果表明,剪切速度主要影响筋土界面的内摩擦角,对筋土界面黏聚力几乎没有影响,随着剪切速度的增加,内摩擦角变大,导致筋土界面抗剪强度增大。筋材空隙率主要影响筋土界面黏聚力大小,空隙率越大,筋材肋条对土颗粒的约束作用越小,筋土界面抗剪强度降低。筋土界面抗剪强度受土体含水率的影响较大,随着土体含水率的增加,筋土界面黏聚力和内摩擦角都明显减小,导致筋土界面抗剪强度显著降低。

The direct shear tests between reinforcement material and soil interface are conducted considering different shear speeds,different void ratios of reinforcement material and different moisture contents of soil. And the influences of different factors to shear strength are analyzed. The test results show that shear speeds affected the friction angle mainly but had little effect on the cohesion. The friction angle got bigger with the shear speeds increased which resulted an increasing of shear strength. On the other hand,the cohesion was influenced by different void ratios of reinforcement material mainly. With the reinforcement material void ratios increased,the constraint effects of the ribs to soil reduced and the shear strength got smaller. The shear strength is influenced strongly by soil moisture content. It is shown that with the increases of soil moisture content,the cohesion and friction angle both reduced significantly which resulting a reduction of shear strength.