长江口袋装砂围堤稳定分析方法探讨

Discussion on stability analysis of bagged-sand dike at Yangtze River estuary

为使土工织物袋装砂围堤的稳定计算简单易行且更加符合实际,针对长江口袋装砂围堤工程,分析了袋装砂围堤土工织物的加筋机理,指出了常规袋装砂围堤稳定分析方法存在的缺陷,从理论上导出了袋装砂围堤拟凝聚力公式。算例表明,利用拟凝聚力进行围堤稳定分析,既充分考虑了土工织物加筋对围堤稳定的有利影响,又修正了极限平衡法不能直接考虑土工织物变形对稳定分析影响的缺陷。对软基袋装砂围堤工程的稳定分析具有一定的指导意义。

To obtain more convenient and practical stability analysis method for geotextile bagged-sand dike, we analyze the reinforcement mechanism of geotextile bagged-sand dike according to several dike projects in Yangtze River estuary, and the disadvantages of conventional stability analysis method for bagged-sand dike are pointed out, and the formula of quasi-cohesive force of bagged-sand dike is deduced theoretically. The examples show that the stability analysis of bagged-sand dike using quasi-cohesive force takes account the beneficial effects of reinforcement of geotextile and the defects that the limit equilibrium method could not consider influence from geotextile deformation on stability analysis. The presented method has valuable mean-ings to stability analysis of bagged-sand dike on soft foundation.