降雨入渗对川藏公路102滑坡群2#滑坡体稳定性影响分析

Rainfall Infiltration on the Stability of the No.2 Landslide at Sichuan-Tibet Highway

川藏公路102滑坡群中2#滑坡规模最大,通过对该滑坡体现场取样,在室内分别进行颗分、击实、渗透以及剪切试验,试验数据分析和FLAC3D数值计算表明,该巨厚松散型滑坡主要由古冰碛物和松散体冲洪积物构成,降雨是诱发滑坡的主要因素之一。

The 102 Landslide Group is located in Yigong Town, Bomi County of Linzhi, Tibet. They are on the right bank of Purlung Tsangpo River, which is the first tributary of Brahmaputra River. This landslide group is near the 102 Service Station of Sichuan-Tibet Highway, and is about 60 km to the east of Bomi and 100 km to the west of Linzhi. The No. 2 Landslide has the largest scale among this landslide group. The laboratory testing, such as, grain size distribution, Proctor test, permeability and direct shear tests are performed on samples from the landslide zone. Both the tests results and the FLAC3D numerical simulations show that the failed body is composed of glacial moraine and alluvial deposits. The rainfall is one of the main factors triggering the landslide.