敏感因素劣化对导堤边坡稳定性影响的数值模拟

以吴淞导堤工程为案例,基于超声波现场检测及室内强度试验、探地雷达现场检测试验、潜水员水下探摸及测量结果,分别评价导堤在长期运营过程中护面混凝土结构、内部堆石结构、导堤两侧坡度变化以及两侧冲淤演变等敏感因素的劣化程度,并采用有限元数值模拟方法研究导堤护面混凝土结构等4种敏感因素劣化对导堤边坡变形及稳定性的影响。结果表明:导堤护面混凝土及内部堆石结构弹性模量与导堤水平位移最大值均呈负指数关系;导堤安全系数随着坡度的增大而呈现出近似线性减小;导堤位移的最大值随着导堤左侧淤积和右侧冲淤高程的增加呈线性增大,在实际加固维护方案设计中应该引起重视。

Numerical simulation of effect of sensitivity factor degradation on stability of jetty slope

A case study of the Wusong Jetty during long-term service is presented. Based on the results of field ultrasonic testing, laboratory strength testing, ground-penetrating radar testing, and underwater detection and measurement by divers, the degrees of degradation of sensitivity factors, including the concrete structure for the protective face, the internal rockfill structure, and the variation of the slope and evolution of erosion/deposition on both sides of the jetty, were evaluated. The effect of degradation of the four sensitivity factors on the deformation and stability of the jetty slope was investigated using the finite element numerical simulation method. The results show that the elastic moduli of the concrete structure for the protective face and internal rockfill structure exhibit negative exponential relationships with the maximum horizontal displacement of the jetty; the safety factor of the jetty decreases linearly with the increase of the slope, approximatively; and the maximum displacement of the jetty increases linearly with the increase of elevation induced by deposition on the left side and erosion/deposition on the right side of the jetty. The phenomena should be given more attention in design of schemes for reinforcement and maintenance in practice.