边载作用下隔离桩隔离效果的影响因素研究

发布时间：2018-10-30 19:33

【摘要】：以港珠澳大桥海底沉管隧道基础沉降控制研究为科研背景,为研究岛头边载作用下隔离桩隔离效果的影响因素,进行了8组室内模型试验,分别研究了隔离桩桩长、桩径、桩间距及隔离桩距减沉桩距离S1等因素对隔离效果的影响。试验结果表明:减沉桩桩身最大轴力、弯矩随隔离桩桩长的增加而减小,并且当隔离桩桩长达到所需的嵌固深度时,对弯矩的隔离效果非常显著;隔离桩桩径的增加或桩间距的减小不仅提高隔离桩对竖向变形的隔断能力,同时也使得隔离桩之间土拱效应增强,减沉桩桩身最大轴力、弯矩随着隔离桩桩径的增加而减小,随隔离桩桩间距的减小而减小,同时,当隔离桩桩间距达到8D时,对轴力与弯矩的隔离效果可以忽略不计;减沉桩桩身最大轴力随S1的减小而减小,而S1的变化对弯矩的隔离效果影响不显著;研究成果可为隔离桩的应用提供较好的参考。
[Abstract]:Based on the research background of foundation settlement control of underwater immersed tunnel of HongKong-Zhuhai-Macao Bridge, and in order to study the influencing factors of isolation effect of isolated pile under the action of island head side load, eight groups of indoor model tests were carried out, and the length and diameter of isolated pile were studied respectively. The influence of the distance between the piles and the distance between the isolated piles and the distance S _ 1 on the isolation effect. The test results show that the maximum axial force and bending moment of the pile body decrease with the increase of the length of the isolated pile, and when the length of the isolated pile reaches the required embedded depth, the isolation effect of the bending moment is very significant. The increase of the diameter of the isolated pile or the decrease of the distance between the piles not only increases the separation ability of the isolated pile to the vertical deformation, but also enhances the soil arch effect between the isolated piles, and reduces the maximum axial force and bending moment of the pile body with the increase of the diameter of the isolated pile. At the same time, the isolation effect of axial force and bending moment can be ignored when the spacing of isolated pile is up to 8D. The maximum axial force decreases with the decrease of S1, but the variation of S1 has no significant effect on the isolation effect of bending moment, and the research results can provide a good reference for the application of isolated pile.
【作者单位】：东南大学土木工程学院;东南大学混凝土及预应力混凝土结构教育部重点实验室;
【基金】：国家科技支撑计划项目(2011BAG07B01)
【分类号】：TU473.1

【参考文献】