大型堆积体滑坡地下水的作用分析及治理措施

Analysis of Groundwater Effect and Treatment Measures for Huge Accumulated Landslide

一公路滑坡是典型的大型堆积体滑坡,1999年采取预应力抗滑明洞结构支挡等措施后滑坡得以稳定,但其深部却在持续蠕动变形,2008年强降雨期间其深部发生较大变形,有重新复活的迹象。根据现场踏勘和地质勘察结果分析可知,地下水的长期作用以及雨季降雨是导致滑坡长期蠕动变形的主要原因,滑坡原有的排水设施年久失效以及现有抗滑明洞支档结构改变了地下水渗流路径是造成滑坡长期蠕动变形的重要因素。为消除地下水的影响,2012年增设了深部排水隧洞疏排地下水,监测结果表明滑坡深部位移变形显著收敛且地下水排水效果良好。本文分析滑坡产生的原因,阐述其治理过程,可供类似的滑坡治理工程借鉴。

Certain highway landslide was a typical huge accumulated landslide. In 1999 prestressed open cut retaining structure and other measures were adopted,then the landslide became stable gradually,but deep landslide deformation lasted continuously. D uring the heavy rainfall period in 2008,deep displacement increased substantially which indicated that the landslide could be reactivated. The analysis results of field exploration and geological survey data showed that the long termgroundwater effect and heavy rainfall during rainy season were the major causes.Meanwhile other factors were that original deep drainage facilities could not function effectively and groundwater seepage channels were changed due to the construction of open cut tunnels. In order to eliminate groundwater adverse influences,in 2012 deep drainage tunnels was constructed to discharge groundwater. Monitoring results oflandslide deep displacement showed that deep displacement was converged. Meanwhile the drainage effect was very well. This paper analyzed the causes and treatment process of this landslide,which could provide reference for similar treatment engineering oflandslide.