干湿循环下花岗岩残积土抗剪强度衰减与边坡稳定性折减度的研究

Study on Shear Strength Attenuation of Granite Residual Soil and Slope Stability Reduction under Wetting-Drying Cycle

笔者通过室内干湿循环试验模拟自然环境下的季节性干湿交替现象,研究了花岗岩残积土抗剪强度在干湿循环下的衰减规律。试验结果表明:花岗岩残积土抗剪强度的衰减主要体现在前3次干湿循环作用中,后续的干湿循环作用下产生衰减的幅度较小,且衰减趋于平缓稳定。在干湿循环试验的基础上,探讨了干湿循环下花岗岩残积土抗剪强度衰减的主要机理,研究了干湿循环作用对边坡稳定性安全系数的折减,并对折减程度进行了量化分析。研究成果对边坡稳定性分析和在边坡支护过程中合理地考虑支护结构具有重要的借鉴和参考意义。

The attenuation law of shear strength of granite residual soil under wetting-drying cycle is studied by simulating the seasonal wetting-drying alternation phenomenon under natural environment through indoor wettingdrying cycle test.The test results show that the attenuation of shear strength of granite residual soil is mainly reflected in the first three wetting-drying cycles,and the attenuation amplitude is small under the subsequent wetting-drying cycles,and the attenuation tends to be stable.Based on the wetting-drying cycle test,the main mechanism of shear strength attenuation of granite residual soil under wetting-drying cycle is discussed,the reduction of safety factor of slope stability under wetting-drying cycle is studied,and the reduction degree is quantitatively analyzed.The research results have important reference significance for slope stability analysis and reasonable consideration of supporting structure in the process of slope support.