双排板桩堤施工过程的数值模拟与设计优化

Numerical simulation and design optimization in the construction of double-sheet-pile dam

为研究施工过程中双排板桩堤在结构-土-水相互作用下的动态安全问题,采用ABAQUS软件,开展了桩间土分层填筑过程的有限元数值模拟,研究了板桩堤结构的内力发展过程,重点分析了桩间联系梁刚度对板桩堤结构应力变形的影响。计算结果表明:当桩顶变位相对自由时,板桩堤结构的弯矩发展规律是在桩间填土过程中逐渐向桩顶发展,最终形成填土侧主要受拉的弯矩分布特征;随着桩顶联系梁刚度增加,桩顶变位减小,板桩所承受的弯矩受拉侧从填土侧逐渐转变到外侧受拉,最大剪力位于填土前的泥面附近,且板桩最小变形工况对应的板桩内力最小。该成果对双排板桩堤的优化设计具有一定的指导意义。

To study the dynamic safety of double-sheet-pile dams under soil and water＇s mutual influence in the course of construction, software ABAQUS was applied for the definite element numerical simulation of staged filling process of soil between piles, the study of internal force development process of sheet pile structure, and the analysis of effects of link beam stiffness on the stress deformation of sheet pile dam structure. Results show that with relatively free displacement of pile top, the bending moment of sheet pile dam structure develops toward pile top in the course of staged filling of soil between piles, and finally form bending moment distribution characteristics of main tension at soil filling side; however, with the increase of the link beam stiffness, the main tension side shifts from the soil filling side to the lateral side and the maximum shearing force appears nearby the original mud surface before soil filling; moreover, the minimum deformation of sheet pile corresponds the minimum internal forces. The results provides guidance for the optimal design of double-sheet-pile dams.