南水北调中线一期工程潞王坟膨胀岩试验段渠坡塌滑机理分析

The Mechanism Analysis about Channel Slope Landslide of Luwang Grave Swelling Rock (soil) Test Section of the South-to-North Water Transfer Project

南水北调中线工程潞王坟膨胀岩(土)试验段设计桩号SY1+179.7～SY1+240.5段左岸边坡二—四级马道之间,施工开挖过程中,先后发生了3次塌滑。从渠坡工程地质条件出发,通过对该段渠坡地层岩性特征、粘土岩的膨胀性及其结构面性质等方面进行分析,阐明了渠坡塌滑主要受粘土岩的膨胀性及软岩结构面与边坡坡向的组合关系所控制,粘土岩的膨胀性是边坡塌滑的决定性因素,结构面与渠坡的不利组合为渠坡塌滑创造了有利的边界条件。

The landslide has occurred between 2～4 class horses road of Piles SY1 ＋179.7 ～ SY1 ＋240.5 left bank slope at Luwang grave expansive rock（soil） test section of the South-to-North water diversion for 3 times during the project was construct and excavate.In this paper,based on the engineering geological conditions of channel slope,the lithologic characters of strata,and expandability of claystone and its features of structural plane were analyzed.Those showed that the landslide of channel slope were mainly controlled by expandability of claystone and the combination of structural plane of week rock and slope aspects,the expandability of claystone was the determinate factor of landslide and the unfavorable combination of structural plane and channel slope is beneficial boundary conditions of the landslide.