桥墩-承台-桩基体系动静刚度原型试验研究  

Experimental Study on the Dynamic Stiffness of Pier-Cap-Pile Foundation System

作　　者：刘建磊 程永黎 李林杰 LIU Jian-lei;CHENG Yong-li;LI Lin-jie(Railway Engineering Research Institute,China Academy of Railway Sciences Group Co.,Ltd,Beijing 100081,China;Shuohuang Railway Co.,Ltd.,Suning 062350,China)

机构地区：[1]中国铁道科学研究院集团有限公司铁道建筑研究所,北京100081 [2]朔黄铁路发展有限责任公司,河北肃宁062350

出　　处：《铁道标准设计》2018年第11期73-76,共4页Railway Standard Design

基　　金：朔黄铁路发展有限责任公司科技创新项目(SHGF-14-50)

摘　　要：为研究桥墩-承台-桩基体系动刚度和承载能力的关系,采用机械阻抗法进行原型试验研究,以分析体系整体动静对比系数的取值,以及整体体系动刚度与单桩动刚度的关系。动力测试试验分3个阶段进行,对待测模型桥墩的墩身和承台进行整体切割。在切割前后分别测试桥墩-承台-桩基体系动刚度、承台-桩基体系动刚度以及单桩动刚度,并在切割墩身之后对承台-桩基体系进行静载试验。测试结果表明:(1)桥墩-承台-桩基体系的整体动刚度与承台-桩基体系的动刚度值较为接近;(2)在低频段整体动刚度接近于单桩动刚度的4倍,表明整体动刚度一定程度上能反映基础的整体承载力;(3)承台-桩基体系的平均动静对比系数为1. 78。因此,总体上看基础整体动刚度能反映基础整体承载力状态。In order to study the relationship between dynamic stiffness and bearing capacity of thepier-cap-pile foundation system, mechanical impedance method is employed to analyze the dynamic andstatic contrast coefficient of the whole system, and the dynamic stiffness of the single pile. Dynamic testsare carried out in three stages, in which the pier and the cap of the model are segmented according to thetest plan. The dynamic stiffness of the pier-cap-pile foundation system, the cap-pile foundation systemand the piles are tested respectively before and after segmenting. Then, loading tests of the cap-pilefoundation system are carried out after pier segmentation. The results show that： （ 1 ） the dynamicstiffness of the pier-cap-pile system is close to that of the cap-pile foundation system; （2） the dynamicstiffness of the pier-cap-pile system is nearly four times that of the single pile in low frequencies,indicating that the overall dynamic stiffness can reflect the overall bearing capacity of the foundation; （3）the average static and dynamic contrast coefficient of the pile-foundation system is 1. 78. Accordingly,the overall dynamic stiffness of the foundation can reflect the overall bearing capacity of the foundation.

关 键 词：铁路桥梁 桥墩 桩基础 机械阻抗法 动刚度 静载试验 

分 类 号：TU473.1[建筑科学—结构工程]