土钉轴力分布规律及经验调整系数研究

Study on the distribution of soil nail axial force and the empirical coefficient

土钉轴力是土钉墙验算的重要内容,国内相关规范对土钉轴力的计算方法也在逐渐改进。基于FLAC3D软件进行数值模拟,分析了土钉轴力的分布规律,探讨了现行规程计算土钉轴力的适用性,并对经验调整系数取值影响因素进行了探讨,其结论对工程设计有参考价值。研究结果表明,以朗肯土压力理论为基础的土钉墙分析方法,在某些情况下并不能得到满意结果。土钉轴力的大小及分布规律,不仅与开挖面以上的土层有关,还与开挖面以下土层性质有关,现有的计算方法中未考虑这个因素。通过与模型试验结果比较,结论得到了部分验证。

As an important content of checkingsoil nailing wall,the soil nail axial force is closely related to the engineering safety,and the calculation method of the axial force of soil nail is also gradually improved. Based on the FLAC^3 D numerical simulation, the distribution of soil nail axial force is analyzed, the applicability of the currentcodes to calculate the axial force of soil nails is discussed,and the influence factors of the value of the empirical coefficient are discussed. The results show that the analysis method based on Rankine earth pressure theory cannot get satisfactory results in some cases. The value and distribution of soil nail axial force is not only related to the soil layer above the excavation face,but also with the nature of the soil layer below the excavation face,and this is not considered in the existing calculation methods. By comparing with the results of model test,some conclusions have been verified.