基于模糊因素的岩质边坡地震稳定性多模型组合评价

岩质边坡地震稳定性评价是岩土边坡地震失稳防治的基础工作,针对评价过程中评价因素的多源模糊性,借鉴工程可变模糊集理论,将模糊可变评价模型应用于岩质边坡地震稳定性评价中。综合考虑岩质边坡内在结构和外部自然条件,选取岩土体特性、新构造运动特征、坡高、坡角、年均降雨量和场地地震烈度6个指标作为评价指标体系并建立等级标准;将改进熵权算法引入该模型中,利用指标实际数据离散性求权重;通过改变模糊可变评价模型参数对岩质边坡地震稳定性进行线性与非线性组合评价,并将均值作为最终评价结果。将该方法应用于天然边坡与路堑边坡实例中,结果表明,模糊可变评价模型评价结果合理、客观,具有更高的可靠性与稳定性,为岩质边坡地震稳定性评价工作提供了一种新的研究方法与思路。

Multiple model combination evaluation of seismic stability of rock slopes based on fuzzy factors

Evaluation of seismic stability of rock slopes is the important foundation for prevention of seismic unstability of rock and soil slopes. In view of the multi-source and fuzzy characteristics in evaluation process, by using engineering variable fuzzy set theory for reference, fuzzy variable evaluation model is applied to evaluate the seismic stability of rock slopes. First, by comprehensive consideration of the rock slopes internal structure and external natural conditions, six parameters including the characteristics of the geotechnical body, the characteristics of the neotectonics, slope height, slope angle, the annual average precipitation, site seismic intensity are selected as the indices for evaluation index system and established rating standard, then the weights of evaluation factors in the model are obtained from the index practical data discreteness by using improved entropy weight method; finally, by changing the fuzzy variable evaluation model parameters to evaluated seismic stability of rock slopes by linear and nonlinear, and obtained stability level by mean value. The method has been applied to natural slope and cutting slope instances. The results show that the fuzzy variable evaluation model results are reasonable and objective; and they have better reliability and stability so as to provide a new research method and idea for seismic stability of rock slopes.