静载及循环荷载下砂土中复合桩基承载特性模型试验研究  

Research on model tests of bearing capacities for composite pile foundation under static and cyclic loading in sand

作　　者：胡娟[1,2] 宋一凡[1] 贺拴海[1] 

机构地区：[1]长安大学公路学院,陕西西安710064 [2]陕西铁路工程职业技术学院,陕西渭南714000

出　　处：《大连理工大学学报》2015年第3期305-311,共7页Journal of Dalian University of Technology

基　　金：交通运输部建设科技项目(2012319223020);中央高校基本科研业务费专项资金资助项目(2013G1502019);陕西铁路工程职业技术学院常规项目(2013-48);陕西省教育厅专项科研计划资助项目

摘　　要：随着桩基的广泛应用,对桩土间承载机理的研究越来越多.根据桩土间接触作用,采用大比例桩土模型进行了室内试验.为更好地仿真桩土间的摩阻效果,试验过程中对桩的材料进行了改进,并开发了一套竖向静载及循环加载系统和测试装置.通过对砂土中复合桩基进行竖向静载和循环加载试验,基于模型桩基的桩顶沉降、桩身轴力、桩侧摩阻力及桩底反力等数据的分析,发现桩基承载性能随加载次数增加而增强:桩顶沉降提高了29.6%,桩身轴力提高了40.4%,桩侧摩阻力下降,桩底反力提高了50%,且桩基极限承载力提高了25%,为继续研究服役期桩基不同加载条件下的桩-土作用提供了数据支撑.With the wide application of pile bearing mechanism between the pile and soil. foundation, there are more and more researches on the According to the contact between pile and soil, a large proportional pile-soil model test was adopted, and in order to simulate the friction effect of pile and soil better, the pile material was improved in the test, and a set of loading and measuring apparatuses were developed to adapt the vertical static and cyclic loading. The tests of vertical static and cyclic loading were taken on the composite pile foundation in sand, and the pile top settlement, the axial force and lateral friction resistance of pile, pile bottom reaction force were analyzed. The experimental results show that the pile performances are enhanced with the increasing of the loading numbers： the pile top settlement being improved by 29. 6%, the axial force being improved by 40. 4%, lateral friction resistance being decreased, pile bottom reaction force being increased by 50%, and the pile ultimate bearing capacity being increased by 25%, which provides a reference for the study of interaction between pile and soil under different loading conditions for the serviced pile foundation in the future.

关 键 词：静载 循环荷载 复合桩基 承载特性 模型试验 

分 类 号：U448[建筑科学—桥梁与隧道工程]