含水率对不同加筋方式黄土强度的影响

Influence of Moisture Content on Strength of Loess with Different Reinforcements

通过室内静三轴剪切试验,探讨了3种不同加筋方式和5种不同含水率作用下加筋黄土的强度特性。试验结果表明,在黄土中布筋能大幅度降低含水率变化对土体强度的影响;含水率相同时试样强度随加筋层数、围压的增大而增大;围压相同、加筋层数相同的试样强度随含水率的增大而明显减小,表明加筋黄土强度具有水敏感性,加筋黄土的水敏感性随加筋层数的增加有增强趋势;在一定含水率范围内,加筋土莫尔—库伦强度指标随含水率的增大而呈线性减小,内摩擦角的下降比黏聚力的下降更明显,在此基础上建立了加筋黄土抗剪强度与含水率之间的关系式,拟合关系较好。

A series of triaxial test were conducted to test three different reinforced methods and the strength characteristics of the reinforced loess with five different moisture contents respectively. The result indicated that the reinforcement could significantly reduce the influence of the moisture content on the strength of lo- ess; the strength increased with the number of reinforcement layers and the strength of the ambient pressure when the moisture content kept the same, decreased with increase of the moisture content when the ambient pressure and number of the reinforcement kept the same, which demonstrated that the reinforcement loess was of water sensitive and the sensitivity became stronger with the number of the reinforcement layers. Within a certain moisture content limit, the strength index of Mohr-Coulomb decreased linearly with the increase of the moisture content and the internal friction angle reduced much more than the cohesion. Finally an equation was established to link the shear strength of the reinforcement loess and the moisture content, which were well matched.