大型岩质高边坡稳定性分析与综合设计

Stability Analysis and Comprehensive Design of High Rock Slope

以福建省某市政公路龟山高边坡为例,对大型花岗岩质高边坡的地质条件与变形破坏模式进行了分析,并采用赤平投影法和强度折减法对边坡的稳定性进行了综合性评价。分析表明:受弱、微风化花岗岩岩体与结构面强度控制,该边坡的破坏形式以楔形体破坏与浅层失稳掉块为主;不同优势结构面组合对边坡稳定性的影响较大,其中,受D3优势结构面组合控制的边坡稳定安全系数最低。基于分析结果,提出了边坡设计时应综合考虑坡体开挖、坡面防护、危岩落石防护与动态设计,以确保设计措施安全可靠。

Taking GUISHAN high slope along a municipal highway in Fujian province as an example,the geological conditions and deformation failure mode of large-scale high granite slope were analyzed,and the stability was comprehensively evaluated by the method of stereographic projection and strength reduction.The analysis shows that,the failure modes of this slope,under domination of the strength of the moderate and weak weathered granite rock mass and its structural planes,prefer to wedge breakage and instable block drop in shallow layers;and the different combinations of preferred planes have large impact on the slope stability,wherein the safety factor under domination of D3 preferred plane combination is minimum.Depending on this result,the comprehensive design incorporating slope excavation,surface protection,dangerous and falling rocks protection and dynamic design,was proposed in order to ensure the safety and reliability.