基于大型剪切试验的西藏某露天矿高原碎石土力学特性研究

Study on mechanical properties of plateau crushed stone soil in an open mine in Tibet with large scale shear test

高原碎石土由于其力学成因较特殊,因而具有大颗粒多、联结力很小的特点。大型矿山的边坡失稳绝大多数是由于剪切破坏引起的,准确把握岩土体强度特性是稳定性分析与治理工程设计的关键。岩土体剪切强度试验方法主要根据工程需要和土体特点来选用,根据大试样尺寸、且不失碎石土本身结构的原则,进行了原状碎石土样以及和原状土相同干密度、不同含水率、含有不同量石灰重塑样以及和原状样具有相同状态的重塑样的大型直剪试验与常规的应变控制式的小型剪切试验,通过试验结果对比揭示岩土的结构性强度特征。

As mechanical causes of plateau crushed stone soil is spectal, tneretore, has much large soil particles and its join forces is small. Most slope instability of large-scale mining is due to shear failure, accurate grasp of the strength characteristics of rock and soil is the key to the stability analysis and the design of control engineering. The method of shear strength test of rock and soil based on the project needs soil characteristics. According to the principle on large scale with the structure of the crushed stone soil, undisturbed samples and same densty, different moistures remoulded samples, different lime content remoulded samples, and sane moistures remoulded samples are taken to large scale direct shear tests. The samples are also taken to conventional small strain controlled shear tests. The results reveal to compare the structural strength characteristics of soil.