不平衡弯矩作用下基桩全为受压桩的厚承台受力性能研究  

Study of behavior of the deep pile cap under unbalanced moment with all piles being compressive ones

作　　者：郭宏磊[1] 

机构地区：[1]江汉大学,湖北武汉430000

出　　处：《土木工程学报》2012年第12期136-142,共7页China Civil Engineering Journal

基　　金：国家自然科学基金(50878097);湖北省教育厅重点项目(D20083401);武汉市教育局重点项目(20070703)

摘　　要：进行不平衡弯矩作用下基桩全为受压桩的厚承台试验、有限元与理论研究,描述该种承台从开裂前到开裂后直至冲切三个阶段的破坏情况,指出该承台的破坏为以冲切为主的弯冲破坏,说明承台在冲切破坏阶段的基桩反力可近似采用线弹性阶段的数值,阐述该种承台存在空间桁架传力机理,表明因所设计的模型承台的斜压杆传力体系中存有单个对称轴,而使其应力集中程度有所下降的破坏特点,显示出承台的上部结构宜对称布置的设计原则,给出这一承台承载力计算的全过程,并经试验结果的验证,证明计算的合理性。所得结论可对工程设计提供帮助。The experimental analysis, finite element and theoretical studies of the deep pile cap under unbalanced moment with all piles being compressive ones are conducted, in which the failure circumstances in the three stages from pre-erack, post-crack until punching are described. It is pointed out that the main failure type of this kind of deep pile cap is bending-punching failure with prevailing punching. It is explained that the pile counterforce during punching failure period of the pile cap can approximately adopt the values of linear elastic stage. Load transferring mechanism of spatial strut-and-tie （SST） is found in this kind of the deep pile cap. The damage character is pointed that since solely directional symmetry axis exists＂ in extents decrease to some extent. symmetrically. The whole process The obtained conclusions may aid the strut transferring load system of designed model pile cap, the stress concentration Based on the research, the superstructure on the pile cap should be of the pile cap bearing capacity calculation is the engineering design. arranged given and validated by the test results.

关 键 词：不平衡弯矩 受压桩 厚承台 空间桁架 

分 类 号：TU375[建筑科学—结构工程]