非连续变形分析（DDA）方法在高海拔高烈度地区公路边坡稳定性分析中的应用

分析了天山某公路边坡发育的工程地质特征,并结合高海拔高烈度地区公路冻融作用强烈的特征,引入了冻融折减系数,采用非连续变形分析(DDA)方法模拟了该段边坡变形破坏全过程。结果显示,在各种内外营力的综合作用下,目前该段边坡处于时效变形阶段,变形破坏主要集中于浅表部;DDA模拟结果表明,在天然状态下该段边坡处于基本稳定状态,但在地震工况及地震+冻融工况下易于发生浅表层的滑移式崩塌。结合以上边坡变形破坏特征,提出了采用清除坡表危岩+插别加固的综合治理措施。 

Application of DDA in study on highway slope stability in the high-altitude areas of high seismic intensity

On the basis of field survey, this paper analyzed engineering geological characteristics of a highway slope located in Tianshan mountain. Moreover, combined with the intensive freeze-thaw effect characteristics in high altitude and high seismic intensity areas, the discontinuous deformation analysis program was applied to simulate the whole process of slope deformation and failure vividly on the basis of introducing the freezing and thawing reduced coefficient. For the time being, the solpe selected is in the state of time-dependent deformation stage, the main deformation and failure phenomena are lacated in shallow surface. The simulated results indicated that the slope selected was in steady state at natural condition, whereas, the slope tends to generate slip-style collapse on shallow surface in seismic condition and seismic plus freeze-thaw effect condition. According to the above analysis, this paper comes up with a comprehensive control measure which combines clearing rocks on the surface with inserting steel bar in the rock mass.