旁孔法探测桩基完整性的数值模拟分析

1.广州市广园市政建设有限公司,广州510040;2.广州一建建设集团有限公司,广州510060

桩基;完整性;检测;旁孔法;数值分析

Numerical Simulation Analysis of Pile Foundation Integrity Detection by Parallel Seismic Method
YANG Zhanpeng1,SONG Zhuo2

1.Guangyuan Municipal Construction Co.,Ltd.,Guangzhou 510040,China;2.Canton One Construction Group Co., Ltd., Guangzhou 510040, China

Pile foundation;Integrity;Inspection ;Parallel seismic method;Numerical analysis

DOI: 10.13512/j.hndz.2022.03.15

备注

为评价旁孔法在既有桩基长度和完整性检测方面的适用性,采用数值分析方法对桩顶自由桩基和带承台桩基开展动力分析,研究桩身缺陷、桩-孔间距、承台结构等因素对旁孔法测试结果的影响。分析结果表明:旁孔法用于检测桩基长度时,桩-孔测试间距不应超过1m;对于桩身存在局部缺陷的情况,当测试孔靠近缺陷侧时,首波时深直线斜率有较明显的变化;对与承台连接的既有桩基,桩-孔测试距离越小,桩身浅部断桩、夹泥类缺陷的波形异常特征越明显,但旁孔法难以判别桩-承台连接部位是否存在缺陷。
In order to evaluate the applicability of the parallel seismic method in the detection of the length and integrity of existing pile foundation, the paper conducts dynamic analysis of the free pile foundation and the pile foundation with cap by numerical analysis method,and studies the influence of pile defects,pile-hole spacing and pile cap structure on the test results of the parallel seismic method. The results show that when the parallel seismic method is used to detect the length of existing pile foundation,the pile-hole test spacing should be less than 1 m;for the case of local defects in the pile body, when the test hole is close to the defect side, the slope of the deep straight line at the first wave changes obviously;for the existing pile foundation connected with the pile cap,the smaller the test distance between the pile and the test hole, the more obvious the abnormal characteristics of the waveform of broken pile and mud inclusion defects in the shallow part of the pile,but the parallel seismic method is difficult to identify whether there are defects at the pile-cap joint.
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