非接触桩箱复合基础竖向承载特性分析  

Analysis on vertical bearing characteristics of unconnected caisson-pile composite foundation

作　　者：栾阳 杨阳 戴国亮[1,2] 龚维明[1,2] 贾其军 Luan Yang;Yang Yang;Dai Guoliang;Gong Weiming;Jia Qijun(School of Civil Engineering,Southeast University,Nanjing 210096,China;Key Laboratory of Concrete and Prestressed Concrete Structure of Ministry of Education,Southeast University,Nanjing 210096,China;China Road and Bridge Corporation,Beijing 100011,China)

机构地区：[1]东南大学土木工程学院,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,南京210096 [3]中国路桥工程有限责任公司,北京100011

出　　处：《东南大学学报（自然科学版）》2020年第6期999-1005,共7页Journal of Southeast University：Natural Science Edition

基　　金：国家重点研发计划重点专项资助项目(2017YFC0703408);国家自然科学基金资助项目(51678145,51878160);中国交建重点研发资助项目(2016-zjjt-24).

摘　　要：为研究非接触桩箱复合基础的竖向承载性能,基于室内模型试验,分析了非接触桩箱复合基础的承载力特性及沉降规律.采用离散有限差分多尺度耦合分析方法建模,将模型计算结果与室内试验结果进行对比,从宏、细观分析非接触桩箱复合基础的力学行为特性.结果表明,非接触桩箱复合基础荷载位移曲线为缓降形,下部地基土变形为中间大、两边小.垫层越厚,沉箱沉降越大,但垫层对桩、土变形协调能力越好.沉箱下部垫层颗粒大都向下运动,靠近沉箱边缘的颗粒水平运动明显,垫层颗粒出现明显水平运动的起始点与地基表层土出现沉降的拐点相一致.To study the vertical bearing behaviors of unconnected caisson-pile foundation,the bearing capacity and the settlement feature were analyzed based on a series of indoor model tests.The simulation model was established by a multi-scale method with coupling of discrete element and finite element method.Compared the simulation results with the indoor model test results,the mechanical behavior features of the unconnected caisson-pile foundation were analyzed from macro and micro view.The results show that the loading-displacement curve of the unconnected caisson-pile foundation changes slowly.The vertical displacement of soil on ground surface is large in the middle and small on both sides.The thicker the cushion is,the larger the caisson settlement is,but the compatible deformation capability of the pile and soil is better.The cushion particles under the caisson mainly move downward,and those nearing the caisson edge obviously move horizontally.The position where particle horizontal movement starts obviously is consistent with that of the inflection point of the ground surface soil settlement.

关 键 词：非接触桩箱复合基础 竖向承载力 沉降 离散-有限差分耦合 

分 类 号：TU473[建筑科学—结构工程]