大型集群桩基厚承台空间桁架模型试验及数值模拟分析  

Spatial truss model test and numerical simulation on thick caps of large-scale group piled foundation

作　　者：何泓男 戴国亮[1,2] 刁莹露[1] 

机构地区：[1]东南大学土木工程学院,江苏南京210096 [2]东南大学混凝土及预应力混凝土结构教育部重点实验室,江苏南京210096

出　　处：《土木工程学报》2015年第8期102-109,共8页China Civil Engineering Journal

基　　金：国家重点基础研究发展计划(973计划)(2013CB036304)

摘　　要：进行4个不同厚度、不同配筋方式的34桩厚承台的模型试验,分析承台的破坏模式、开裂荷载、破坏荷载以及桩顶反力分布,基于模型试验结果,以7个厚承台模型进行数值模拟分析,研究大型集群桩基厚承台的受力特性,验证空间桁架模型的合理性,并讨论不同承台厚度和配筋形式对承台的承载性能及桩顶反力分布的影响。结果表明大型集群桩基厚承台符合空间桁架模型的受力特点,承台厚度适当增大和桩顶区域集中配筋均能增强承台的承载力,桩顶反力分布受承台厚度和配筋方式的影响较小,数值模拟的结果与试验结果基本吻合,数值模拟的结果具有一定的参考性。Four thick cap models supported by 34 piles with the different thickness and the reinforcement form of caps were tested, and their failure modes, crack loads, failure loads, and reaction force distribution of pile top were analyzed. Based on the model test results, the numerical simulations of seven thick caps were carried out, and the mechanical characteristics of large-scale group piled foundation were therefore studied. The rationality of spatial truss model was verified, and the effects of the different thickness and reinforcement forms of cap on the bearing behavior of thick caps and the reaction force distribution of pile top were discussed. The results show that the load bearing behavior of thick caps can be approximated with the spatial truss （or strut-and-tie model ）. An appropriate increase of cap thickness and the reinforcement concentrated in the pile top zone can strengthen the bearing capacity of thick cap. However the cap thicknesses and reinforcement forms have little influences on the distribution of reaction force of the pile top. The numerical simulation results as agreed well with the model test results, can be relevant to the design work.

关 键 词：厚承台 集群桩基 空间桁架模型 模型试验 数值模拟 

分 类 号：TU473.1[建筑科学—结构工程]