基于塑性应变能理论的边坡动力稳定性研究

Research on dynamic instability mechanism of slopes based on plastic strain energy theory

由于地震作用的随机性和复杂性,使得边坡动力稳定状态的判定较静力问题复杂许多,目前还未形成统一且公认的动力失稳判别准则。将塑性应变能理论和突变理论应用到边坡动力稳定分析中,以边坡震后总塑性应变能突变为失稳判别标准来确定边坡动力安全系数。对算例边坡进行动力稳定分析表明:相比于塑性区贯通判据和关键点位移突变判据,塑性应变能判据受人为因素影响较小,计算结果更具客观性,且给出的安全系数准确性有保证,是分析边坡动力稳定问题的较优选择。

Due to randomness and complexity of seismic action,the instability mechanism of slopes in dynamic analysis is obviously different from that in static analysis.At present,there is no uniform and well-recognized dynamic instability criterion of slopes.In this paper,the plastic strain energy theory and the catastrophe theory are applied to the dynamic stability analysis of a slope,and dynamic safety factor of the slope is determined according to the sudden change of the total plastic strain energy after the earthquake.The dynamic instability analysis of the slope shows that the plastic strain energy criterion is less affected by human factors than the criterion of plastic zone penetration and the criterion of key point displacement mutation.It turns out that the calculation result is more objective and the accuracy of the safety factor is guaranteed.Therefore the proposed method can be a better choice for dynamic instability analysis of slopes.