生态袋与粘性土界面摩擦特性试验研究

Experimental Studies on Interface Friction Characteristics of Eco-bag with Cohesive soil

生态袋与土接触面的作用特性对各类生态护坡工程的设计计算至关重要。通过利用TKA-DDS-20A型液晶微控中型土直剪仪,进行生态袋与粘性土界面摩擦特性试验,探讨土体压实度和含水率变化对生态袋与粘性土界面特性的影响。试验结果表明:生态袋与粘性土界面特性的应力-应变关系表现出典型的非线性特征,剪切强度随法向压力的增大而增大,界面特性服从摩尔-库伦强度理论;生态袋与粘性土之间界面特性因压实度和含水率的变化而异,其中受压实度影响变化的规律明显,随着土体的压实度增高,在生态袋与粘性土之间发生较小相对位移的情况下,界面剪应力增加显著。高含水率下,随着压实度增高粘性土与生态袋界面强度逐渐降低。

The characteristics of the interface between the ecological bag and the soil are very important for the design and calculation of various ecological slope protection projects.By using TKA-DDS-20A liquid crystal micro-control medium soil direct shear instrument,the friction characteristics test of the interface between the ecological bag and the cohesive soil,and the effects of soil compaction and moisture content on the characteristics of the interface between eco-bag and cohesive soil are discussed.The results showed that,the stress-strain relationship at the interface between the eco-bag and the cohesive soil shows typical nonlinear characteristics.Shear strength increases with increasing normal pressure,and interface characteristics obey Moore-Coulomb strength theory;The characteristics of the interface between the eco-bag and the cohesive soil vary with compaction and moisture content.Among them,the law of change affected by compaction is obvious.The higher the compaction of the soil,the higher the interface friction coefficient and friction angle,the smaller the cohesive force.