基于灰岩地质隧道高边坡压力分散性锚索应用研究

Application on Anchorage Cable with Pressure Dispersion to High Slope in Limestone Geological Tunnel

本文结合实际工程案例,通过理论推导、对比分析,探讨了压力分散型锚索在灰岩地质条件下锚固段应力、岩体蠕变和张拉方式对锚索的影响,并取得以下成果:(1)推导出压力分散型锚索的切应力和轴力公式,对锚索在特殊地质条件下的设计及应用提供参考;(2)考虑岩体的蠕变效应,并推导其本构方程;(3)利用不同荷载张拉后补偿张拉最后整体张拉的方式,有效改善了压力分散型锚索因锚固段长度不同导致应力集中产生破坏的问题,并与监测值进行对比分析,以验证张拉方式的正确性。

Through theoretical deduction,comparative analysis of specific engineering cases,the paper discussed the influence of stress of anchorage section,creep of rock mass and tension mode on the anchorage cable under the condition of limestone geology,and gained the following conclusions:(1)the formulas of shear stress and axial force of pressure dispersion type anchorage cable were derived,which could provide reference for the design and application of anchor cable under special geological conditions.(2)The creep effect of rock mass was considered and its constitutive equation was derived.(3)With the method of compensating the final overall tension after tensioning under different loads,the problem of stress concentration and damage caused by different length of anchorage section of pressure dispersive anchor cable was effectively improved,and by comparison with the monitoring value,the correctness of tension method was verified.