圆矩形吸力式深水防波堤的循环承载力的高效计算方法

AN EFFICIENT CALCULATION METHOD FOR CYCLIC CAPACITIES OF CIRCULAR AND RECTANGULAR SUCTION DEEPWATER BREAKWATER

针对箱筒型基础防波堤的主要问题,提出了圆矩形新型吸力式深水防波堤。根据天津海积软土不排水循环三轴试验数据推导出了其循环强度计算公式,并将循环强度概念与承载力的破坏面理论相结合,建立了圆矩形吸力式防波堤的循环承载力的高效计算方法,得出其循环承载力的破坏包络面大小随着基础深径比的增大而逐渐扩大;随着竖向载荷的增大先扩大再收缩,在竖向载荷较小时,考虑软土循环弱化效应的承载力破坏包络面比循环前大幅缩小。

In order to solve the main problems of the breakwater with cylindrical foundation,a new type of deepwater breakwater named circular and rectangular suction deepwater breakwater was proposed.According to the undrained cyclic triaxial test data of Tianjin marine soft soil,the calculation formula of cyclic strength of soil element was deduced.An efficient calculation method for cyclic capacities of circular and rectangular suction breakwater was established by combining the concept of cyclic strength with the failure envelope theory of bearing capacity.It is concluded that the size of the failure envelope of cyclic capacities for circular and rectangular suction breakwater gradually expands with the increase of the depth-to-diameter ratio of the foundation while it first expands outward and then shrinks inward with the increase of the vertical load.When the vertical load is small,the failure envelope considering the cyclic softening effect of the soft soil is significantly smaller than that without considering the cyclic softening effect.