道路约束条件下静压群桩挤土效应  

Squeezing Effects of Jacked Group Piles by Road Constraint

作　　者：李富荣[1] 孙厚超[1] 

机构地区：[1]盐城工学院土木工程学院,江苏盐城224051

出　　处：《土木工程与管理学报》2016年第2期11-17,共7页Journal of Civil Engineering and Management

基　　金：国家自然科学基金(51378257);住房和城乡建设部科技项目(2013-K3-18)

摘　　要：在分析静压沉桩挤土机理的基础上,采用室内模型试验,研究了道路约束条件下静压群桩挤土效应引起的地表土体变形,包括水平位移和隆起变形,并与工程实测进行了比较分析。试验结果表明,沉桩过程中,仅桩区内地表土体水平位移是先增大后减小,其余各处土体变形均是不断增大的,只是道路外侧土体变形较小,可忽略不计;受道路约束影响,距桩区较近处地表土体水平位移减小,隆起变形增大,且桩区–道路间距离越小,该处土体变形越小,而距道路较近处地表土体变形越大;距道路越近,桩区–道路间地表土体变形越小;在道路另一侧,地表土体最大变形明显减小。工程实测表明,与室内试验结果相比,桩区–道路间土体变形呈现相同的变化规律,但受实际道路约束的影响,实测时道路另一侧土体基本未有变形。因此,静压桩施工必须考虑周边道路、建筑物等约束的影响。Based on the analysis of squeezing effects mechanism of jacked piles,this paper used laboratory model test,researched the surface soil deformation caused by the squeezing effect of jacked group piles by road constraint,including horizontal displacement and upheaval deformation,and compared with the engineering test. The results show that,only the surface soil horizontal displacement of pile area increases at first then decreases,the other soil deformation are increasing on the process of pile driving,but the soil outside the road has the small deformation,that it can be neglected. The surface soil horizontal displacement becomes decreases and upheaval deformation increases away from the pile area affected by the road constraint,and the smaller the distance between the pile area and road,the smaller the deformation,but the bigger the soil deformation away from the road. The closer to the road,the surface soil deformation is smaller between the pile area and road. The surface soil maximum deformation is significantly reduced on the other side of the road. The engineering test shows that,compared with the laboratory test results,the soil deformation showed the same variation between the pile area and road,but the soil has not deformed on the other side of road because of the actual road constraint. Therefore,the surrounding road,building and other constraints must be considered at the time of jacked pile construction.

关 键 词：道路约束 静压群桩 挤土效应 模型试验 工程实测 

分 类 号：TU473.1[建筑科学—结构工程]