边坡塑性区贯通后,不同的贯通程度会得出不同的安全系数。为了克服该判别标准存在的人为随意性,以某经典边坡稳定分析算例,采用ABAQUS有限元分析软件,计算出塑性区贯通判据下的安全系数,与计算不收敛判据和特征点位移发生拐点判据得出的安全系数对比,归纳出边坡失稳时等效塑性应变达到的数量级。计算结果表明:当计算过快的发生不收敛,塑性区尚未贯通,计算不收敛判据下安全系数偏小;本文提出根据等效塑性应变量级指标来判决贯通时刻:最大塑性应变为2×10^-4-5×10^-4,最小塑性应变为5×10^-5-10×10^-5,当塑性应变达到量级,表征塑性区贯通,得出的安全系数较其他失稳判据更合理。
When the slope plastic zone penetrates through, different degree of penetration leads to different safety factors. In order to overcome the misjudgment of standards ^ the safety factor under the criterion of penetrated-through plastic zone was calculated in this paper based on a classical example of slope's stability analysis by using FEM analysis software ABAQUS. It was compared with safety factors under criteritions of the non-converge calculation and displacement at the point of inflection The order of equivalent plastic strain magnitude was summarized for the unstable slope. The calculation results showed that plastic zone has not yet penetrated through if calculation is too fast to converge. The safety factor is relatively small under criteria of non-converge calculation According to equivalent plastic strain magnitude index, the penetration-through time was introduced in this paper. The maximum equivalent plastic strain is in the range of 2×10^-4-5×10^-4 and minimum equivalent plastic strain is in the range of 5×10^-5-10×10^-5. When the equivalent plastic strain magnitude reaches summarized index, the plastic zone has penetrated through, safety coefficient is more reasonable than other criteria.