基于低应变检测法的缺陷桩基动力响应研究

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中图分类号：TQ178;TP391.9 文献标志码：A文章编号：1001-5922（2025）07-0064-04

Abstract：Relying on a reconstruction project in Chengde High-tech Zone，the dynamic response of the defective pile foundation（necking）underlow straindynamic load was studied byusing the methodofcombining field measurementand three-dimensional dynamic finite element numerical simulation，and the results showed thatthedynamicresponseof themissng pile foundation（necking）changed significantlyunder theactionof the low-strain dynamic detection wave，and the amplitude of the reflected wave increased by about 25% for every O.4 m increase in the necking thickness，and there was no significant change in the reflected wave atthe botom of the pile.For every 0. 2m increase in pile diameter in the necking area，the amplitude of the reflected wave in the necking area increased by about 10% . The amplitude of the reflected wave at the bottom of the pile increased by about 8% .For every2 m increase in the distance between the necking areaand the topof the pile，the amplitude ofthe reflected wave increased byabout 13% ，and there was no significant change in the reflected wave at the bottom of the pile.When detecting pile foundation defects with low strain dynamics，underthecondition of ensuring thattheexcitation force and action area remain unchanged，attention should bepaid toobservingthe changes inthe necking area and theamplitude of the emission wave at the botom of the pile，so as to beter determine the defects ofthe pile foundation and provide guarantee for the safety and stability of the superstructure structure.

Key words ：low strain； pile foundation defect；on-site measurement；digital simulation； power response

当前，国内外众多学者开展了许多关于桩基缺陷检测的研究，例如，张云鹏修正了Rayleigh-Love杆件理论，采用理论推导的方法得出了低应变动力测桩的三维传播解析解，认为信号叠加法可以很好的消除高频横波的干扰[1]。（剩余4200字）