云南临沧市某隧道边坡失稳破坏机理研究

THE FAILURE MECHANISM OF A TUNNEL SLOPE IN YUNNAN LINCANG

为研究云南临沧某隧道边坡的失稳破坏机理,文中综合采用现场测绘、原位钻探以及室内滑坡稳定性评价方法对该边坡展开研究。结果表明滑坡纵向长度约250m,平均宽度约190m.滑坡潜在滑动方向146°,滑面平均倾角26°-29°;变形破坏主要发生在浅表层,平均厚度约18m,总方量约70×10^(4)m^(3);稳定性计算结果表明,各强变形区的浅层滑面在天然状态下处于欠稳定-基本稳定状态,暴雨和地震工况下处于不稳定状态,深层滑面在各种工况下稳定基本处于稳定状态;根据变形特征.该滑坡属于渐进后退式滑坡;建议在该滑坡强变形区设置格构锚索进行浅层治理,在中前缘设置抗滑桩进行深层加固。

The instability failure mechanism of a tunnel slope in Lincang.Y unnan was comprehensively studied by on-site survey ing and mapping,in-situ drilling and indoor landslide stability analysis,and evaluation methods.The results show that the landslide is in the shape of inverted water droplets,with a longitudinal length of about 250m and an average width of about 190 m.The potential sliding direction of the landslide is 146,and the average inclination of the sliding surface is 26°~29°.The signs of deformation and instability mainly occur in the shallow layer.The average thickness of the landslide is about 18 m,and the total volume is about 70×10^(4)m^(3).The stability calculation results show that the strong deformation areas of the shallow sliding surface are in an under-stable to basically stable state under the conditions of heavy rain and earthquake.In a stable state,the deep sliding surface is basically in a stable state under various working conditions.According to the deformation characteristics,the landslide studied in this paper is a progressive retreat landslide.It is suggested that lattice anchor cables should be set in the strong de-formation area of the landslide for shallow treatment,and anti-slide piles should be set in the middle front edge for deep reinforcement.