波流冲刷作用下变截面桩承载性能劣化的研究

Research on the Evolution of Load-bearing Performance of Variable Cross-section Piles under the Action of Wave and Current Scour

为研究波流冲刷作用下变截面桩的承载性能,依托厦门第二东通道实体工程,利用数值模拟建立桩土相互作用模型,分析了波流冲刷作用下桩的水平承载特性和竖向承载特性。结果表明,随着冲刷深度增大,桩基竖向极限承载力逐渐减小,但对于整体竖向承载力的削弱不大,当冲刷深度较小时,在设计时可以不予考虑;随着冲刷深度增大,桩基横轴向极限承载力逐渐减小,冲刷6.55 m时H15和H19桩的横轴向承载力分别降低24.75%和21.51%。冲刷对于桩的横轴向承载力削弱极大,在设计时应充分考虑由于冲刷导致的横轴向承载力损失,以保证结构的安全。

In order to study the bearing performance of variable section piles under the action of wave and current scouring, relying on the the Xiamen Second East Passageway Project, a pile-soil interaction model is established by numerical simulation, and the horizontal and vertical bearing characteristics of piles under the action of wave and current scouring are analyzed. The results show that as the scour depth increases,the vertical ultimate bearing capacity of the pile gradually decreases,but the overall vertical bearing capacity is not weakened.When the scour depth is small,it can be ignored in the design;and as the depth increases,the ultimate bearing capacity of the pile foundation in the transverse and axial directions decreases gradually.When the scour is 6.55m,the transverse and axial bearing capacities of the H15and H19piles decrease by 24.75%and 21.51%.Scouring can greatly weaken the lateral and axial bearing capacity of the pile,and the loss of lateral and axial bearing capacity due to scouring should be fully considered in the design to ensure structural safety.