循环侧向加载作用下嵌岩桩变形试验分析  

Experimental Analysis of Deformation of Rock-socketed Piles Under Cyclic Side Loading

作　　者：李海滨[1] Li Haibin(China Railway 18th Bureau Group Third Engineering Co.,Ltd.,Zhuozhou 072750,China)

机构地区：[1]中铁十八局集团第三工程有限公司,河北涿州072750

出　　处：《市政技术》2025年第1期159-166,共8页Journal of Municipal Technology

基　　金：中铁十八局集团有限公司2022年度科研创新项目(C2022-051);中国铁建股份有限公司2022年度科技研究开发计划及资助课题(2022-C1)。

摘　　要：在嵌岩桩承载力设计中常用的p-y方法往往会在嵌固段土-岩交界处出现剪力突变的现象,导致抗剪强度设计值偏大,而基于该设计的抗剪箍筋设置较密,致使混凝土浇筑过程中流动困难。因此,为了进一步明确嵌岩桩在水平荷载作用下的桩身变形分布以及在极限荷载作用下的破坏模式,参考济南轨道交通4号线沿线某立交桥桩基进行的循环侧向加载试验,对比分析了3种箍筋设置方案下桩的失效模式。试验结果表明,试桩在桩顶侧向循环荷载作用下最终均呈现出弯曲破坏而非剪力突变造成的剪切破坏,并在嵌固段上方60 cm处出现塑性铰;p-y方法在抗剪设计中的效果虽然表现不良,但对弯矩的预测则相对更加准确。The p-y method,commonly used in the bearing design of rock-socketed piles,often exhibits a sudden change in shear force at the soil-rock interface of the embedded section,causing the excessive design value of conservative shearing strength.This results in denser shear reinforcement,hindering concrete flow during the pouring process.In order to clarify the deformation distribution of rock-socketed piles under horizontal load and the failure modes under ultimate load,a cyclic lateral loading test was conducted based on the pile foundation of an overpass along Line 4 of Jinan Metro.The failure modes of the piles with three different hoop configurations were comparatively analyzed.The results indicated that the test piles ultimately exhibited bending failure rather than shear failure by sudden change in shear force undercyclic lateral loading at the top of the pile,with plastic hinges at 60 cm above the embedded section;The p-y method isn’t effective for shear design,but the prediction of bending moment is relatively accurate.

关 键 词：嵌岩桩 p-y方法 循环侧向加载 剪切破坏 弯曲破坏 

分 类 号：TU473.1[建筑科学—结构工程]