岩体边坡地震稳定性动安全系数分析方法

在分析几位学者研究成果的基础上,提出一种适合于岩体边坡动安全系数非线性分析的方法,其主要步骤如下:1)确定介质非线性本构模型的参数;2)考虑边坡的外部及自身载荷,进行边坡静力有限元非线性分析,确定滑坡带单元的初始应力;3)在静力分析的基础上,进行边坡动力有限元非线性分析,确定滑坡带单元的动应力时程;4)根据滑坡带单元的初始静应力和动应力时程,计算每一时刻的边坡动安全系数,从而得到边坡的动安全系数时程;5)根据评价标准,进行边坡地震稳定性评价。 根据上述步骤,结合三峡重庆库区某典型滑坡进行了动安全系数分析,结果表明了该方法可行性。本文只是提出一种初步的边坡稳定性评价标准,由于这方面的震害资料尚少,对其可行性的研究还有待于进一步深入。

A Method for Evaluating Dynamic Safety Factor Rock Slope Seismic Stability Analysis

Pseudo-static analysis method is used for seismic slope stability analysis specified by currenttechnical code. In fact, safety factor of seismic slope stability should be a function of time. Dynamic safetyfactor based on nonlinear analysis method is employed for characterizing dynamic stability of rock slope.The main steps are as follows. 1. Determining the parameters of the constitutive relationship; 2. Computing the initial stress of slopeby static analysis; 3. Computing dynamic stress of slope by dynamic analysis; 4. Computing dynamicsafety factor with the static results and the dynamic results; 5. Evaluating stability of slope on the basis ofthe safety factor and the presented evaluation criterion. A typical slope located in the Three Gorge reservoir is analyzed. The results indicate that the presentmethod is feasible. However, for the lack of earthquake hazards, the present evaluation criterion is to befurther validated in the future.