循环荷载下单桩-土-桩帽共同作用分析

发布时间：2018-03-31 22:26

本文选题：单桩-土-桩帽　切入点：循环往复荷载　出处：《长江科学院院报》2015年12期

【摘要】：为探究循环往复荷载作用下层状地基中单桩-土-桩帽的共同作用,基于Mindlin板理论和层状弹性地基模型,结合层状地基中单桩的荷载传递规律,提出一种分析共同作用的方法。首先建立单桩-土-桩帽共同作用刚度矩阵,并利用循环往复荷载下土体压缩模量的衰减特性得到带台单桩的累积沉降及单桩-土-桩帽整体刚度的变化趋势,在此基础上进一步开展算例验证和参数分析。结果表明:计算结果与Butterfield的解非常一致;单桩-土-桩帽整体刚度明显大于单桩刚度,增加单桩的弹性模量可以显著地提高单桩-土-桩帽的整体刚度;当桩径确定时,桩长存在一个最优值使得整体刚度最大;而当桩的长径比大于某一值时,桩长的增加对整体刚度及桩帽的荷载分担比影响较小;循环往复荷载作用下单桩-土-桩帽的整体刚度逐渐增大,且趋于稳定值。
[Abstract]:In order to explore the interaction of single pile-soil-pile cap in layered foundation under cyclic reciprocating load, based on Mindlin plate theory and layered elastic foundation model, the load transfer law of single pile in layered foundation is combined. A method to analyze the interaction is proposed. Firstly, the stiffness matrix of single pile-soil-pile cap interaction is established. Using the attenuation characteristic of soil compression modulus under cyclic reciprocating load, the cumulative settlement of single pile with platform and the variation trend of integral stiffness of single pile-soil-pile cap are obtained. The results show that the results are in good agreement with Butterfield's solution, and the overall stiffness of single pile-soil-pile cap is obviously greater than that of single pile. Increasing the elastic modulus of a single pile can significantly improve the overall stiffness of a single pile-soil-pile cap; when the diameter of the pile is determined, there is an optimal value of the pile length to make the overall stiffness maximum; and when the ratio of length to diameter of the pile is greater than a certain value, The increase of pile length has little effect on the overall stiffness and load-sharing ratio of the pile cap, and the overall stiffness of the pile-soil-pile cap is gradually increasing and tends to be stable under cyclic reciprocating load.
【作者单位】：长江科学院水利部岩土力学与工程重点实验室;中国电建集团华东勘测设计研究院有限公司;华东海上风电省级高新技术企业研究开发中心;
【基金】：国家自然科学基金项目(51308067;41206075;51579227) 中央级公益性科研院所基本科研业务费项目(CKSF2013036)
【分类号】：TU473.1

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