The Research On Seismic Stability Of Filled Subgrade Slope In Red-layer Soft Rocky Ground Area In Western Yunnan

Baoteng (Baoshan-Tengchong) highway is located in"Tengchong-Gengma"earthquake zone belt which is the largest earthquake damage zone in Yunnan. Meanwhile, Western Yunnan red-layer soft rock which has weak water permeability, strong water affinity, and is easy to soften or inflat when meeting the water, and break up (or contraction) when dehydrateing, with low intensity and extremely bad engineering properties. Therefore, it is of strong practical significance to research seismic stability of embankment slope in this region.Fist, this paper studied and summarized the slope seismic stability theory, and researched the history of earthquake in Western Yunnan and the engineering properties of red-layer soft rock, and analyzed the internal and external factors impacting the structural stability of the embankment which is created by earthquake stress.At the same time, using ANSYS finite element software, this article analyzed the quantitative seismic stability impact in detail, which is created by the earthquake wave parameters and the embankment structural parameters, including the dynamic response of the embankment structure under the conditions of different embankment height, slope gradient, slope patterns, incidence angle of earthquake waves and earthquake intesity. Finally, the laws of the dymnamic response of enmbankment structures under the earthquake stress were obtained.At the last, combined with the actual project, focusing on the embankment stability factor, this paper simulated and analyzed the seismic stability of slope using the strength reduction theory in software ANSYS, based on the judge criterion of the development of the plasticity area and the mutation of the node displacement. The analysis of the slope height, slope gradient, incidence angle of the earthquake-wave and other factors influencing on the embankment stability coefficient was performed. And the critical height of the embankment structure under the different earthquake intenty, incidence angle of earthquake-wave and the different slope grade was identified in Western Yunnan red-layer region, which may provide a reference to this project and the seismic design of similar embankment slope projects.This paper is supported by the major social development project in Yunnan Province 2009"Baoshan to Tengchong expressway technological and cultural demonstration project".