开挖边坡松动区的近似解析

介绍了楔形体与开挖坡体模型之间的关系，提出了确定边坡开挖松动区范围的弹性理论分析方法。阐明在用楔形体理论分析出开挖坡体的应力场的基础上，根据一定的坡体材料强度条件（经过安全储备后的摩尔-库仑强度准则和单轴抗拉强度准则），且考虑三向应力状态，计算搜索坡体在该稳定系数下的开挖松动区，由此计算出在坡体自上而下分步开挖过程中每一步开挖施工完成之后相应的松动区来。提出了分析计算坡体开挖松动区的主要步骤，说明在分步开挖过程中，计算搜索每一步开挖后的坡体松动区主要需通过讨论上一步开挖后的坡体应力场、本步开挖卸荷量及本步开挖后产生的松动区范围等问题来实现。最后，用算例较为详细地说明了用弹性楔形体理论解析坡体开挖松动区的具体操作过程。

Approximate analysis of relaxation zone for some cutting slopes by elastic wedge body theory

The relation between wedge body and the model of cutting slope is shown.Then analytical method of relaxation zone for cutting homogeneous slope by elastic theory is given.The stress field of cutting slope can be analyzed by elastic wedge body theory.On the basis of elastic plane-strain theory,the relaxation zone related to one safety factor can be calculated according to Mohr-Coulomb law and single tension intensity principle that are both related to the same safety factor after three-dimensional stress field of the cutting slope is got.After every cutting step is completed during excavating the whole slope,its corresponding relaxation zone can be calculated.The main calculation procedure of relaxation zone for cutting slope is given.After every cutting step is completed during excavating a slope step by step,the corresponding relaxation zone for the whole slope can be calculated by main discussing stress field of the slope after last step,additional value of stress field of the cutting slope on current step and local relaxation zone for the slope related to current step.Finally,explicit calculation procedure of analyzing relaxation zone for cutting slope by elastic wedge body theory and strength criteria of slope material is given in detail by an example.