滑坡基质吸力观测研究

Observation of suction in a landslide

滑坡基质吸力的现场观测,对于运用非饱和土力学理论研究降雨型滑坡判据至关重要。通过对某滑坡基质吸力观测研究,笔者发现,滑坡基质吸力在深度上的变化受滑坡体物质组成分带性的影响,与sweeney得到的边坡基质吸力剖面有差异。观察还发现,滑体非饱和带基质吸力随降雨因素的变化,在非饱和带的上部与次降雨具有对应关系,而在非饱和带的中、下部则无明显的对应关系。

The field observation of suction in the landslide is very important for studying the criterion of the landslide instability induced by heavy rainfall in terms of the theory of unsaturated soil mechanics. It is essential to build a description of suction variation with depth in a landslide. For this purpose an observation well was constructed and observation data in almost half a year have been obtained. The analysis of these data gives us following ideas:Suction variation with depth in a landslide is controlled by the landslide structures and its material composition, and it is different from that described by some other authors.The variation of suction with rainfall in a landslide has a correspondence with primary rainfall at upper part of unsaturated zone, but the situation is quite different at middle and lower part of the unsaturated zone.