The Study On The Mechanism And Stability Of Xiangjiashan Landslide

With the rapid development of expressways especially advanced highways mushrooming in central and western regions in China, the problem of possible slope sliding in the construction of expressways has become more and more obvious. Xiangjiashan landslide is typical one of them, which is found being a large ancient slide as early as its exploration & planning survey, but after comprehensive consideration, expressway was still built through it and meanwhile the slope was reinforced. Because the stability of the slope had not been made quite clear before, it was apparently deformed after continuous heavy rain, and landslide occurred. Although remedial reinforcement works followed one after another on the basis of further geological surveys, the effect of such treatment was not so ideal. The monitoring data shows that it still does not prevent sliding movements of the slope now and such deformation is becoming increasingly serious with the increase of rainfall. If proper measures are not taken in time, security of traffic will evidently be affected and even will result in more tragedies. Therefore, it is very essential and necessary to study the stability of the slope and improve its safety as early as possible.This paper takes the slope of Xiangjiashan as investigated subject. Through the geological conditions and combined with the material about local geography, the author analyses some direct and indirect reasons for landslide. On such bases, the stability of high slope has been evaluated by various methods including back analysis, limit equilibrium and nonlinear finite element method. Meanwhile, the effect of anti- landslide measures is confirmed through analogue simulation in computer and it proves feasible and reasonable to adopt such measures. Furthermore, with the implement of these measures, numerical simulation has been made to assess the design and it has been proved to be proper and right. Therefore,conclusions are drawn as follows:â‘ Through geological investigations and materials related, the shape and the component of the slope have been made clear. The slope is consists of three layers of sliding bodies differing in depth including superficial, middle and deep levels. The surface of the sliding takes on irregular hoof in plane view as well as lens in section view with a sliding area of 70,000 m~2 and volume of 140m~3, which indicates that it belongs to the large scale mixed type of landslide.â‘¡In fact, the landslide of Xiangjiashan was caused by many factors such as the...