硅质岩单面山路堑边坡稳定性影响因素分析

为了研究硅质岩路堑边坡的稳定性影响因素,先通过野外调查,总结出路堑边坡的破坏模式主要为滑移—拉裂破坏和受控于结构面的破坏;然后进行单轴压缩变形试验、抗拉强度试验及直接剪切试验得到硅质岩的物理力学参数,为数值模拟提供依据;最后通过有限元强度折减法,分析边坡坡角、结构面间距、开挖坡率及平台宽度4个因素对坡体稳定性的影响。结果表明,边坡坡角对坡体的稳定性影响最大,其次为开挖坡率。由于硅质岩的特殊破坏形式及单面山路堑边坡破坏模式的多样性,在评价路堑边坡稳定性时需要综合考虑各个因素,不可单凭某一因素来判断。研究成果可为其他硬质岩单面山边坡的稳定性评价及支护结构设计提供参考。

Influential Factors of Stability of Silica Stone Cuesta Cutting Slope

In the aim of investigating the influential factors of stability of silica stone cutting slope, field survey was conducted to conclude that the failure modes of cutting slope are mainly dominated by sliding-tension and discontinuities. In the meantime, the physical and mechanical parameters of silica stone were obtained through uniaxial compressive test, tensile strength test, and direct shear test. On this basis, the influences of four factors, namely, slope gradient, spacing between discontinuities, cutting rate, and platform width, on slope stability were examined through strength reduction in finite element simulation. Results show that among the four factors, slope gradient plays a biggest role in slope stability, followed by cutting rate. Due to the special failure mode of silica stone and the diversity of cuesta cutting slope’s failure mode, various factors, rather than single factor, should be considered while evaluating the stability of silica stone cuesta cutting slope.