基于磁场模型的桩基长度检测信号特性试验研究  

Experimental Study on Signal Characteristics of Pile Foundation Length Detection Based on Magnetic Field Model

作　　者：赵亚宇 邵继喜 杨军 赵鸿彬 朱思佳 姚家丽 ZHAO Ya-yu;SHAO Ji-xi;YANG Jun;ZHAO Hong-bin;ZHU Si-jia;YAO Jia-li(Guangzhou Municipal Engineering Testing Co.,Ltd.,Guangzhou 510520;Guangzhou Construction Co.,Ltd.,Guangzhou 510030)

机构地区：[1]广州市市政工程试验检测有限公司,广州510520 [2]广州建筑股份有限公司,广州510030

出　　处：《广州建筑》2024年第9期68-71,共4页GUANGZHOU ARCHITECTURE

基　　金：广州市建筑集团有限公司科技计划项目([2021]-KJ010、[2023]-KJ011);广东省住房和城乡建设厅科学技术计划项目(2022-K26-503115)。

摘　　要：钢筋笼长度作为影响灌注桩抗拔、抗弯、抗震力学性能和安全稳定性能的重要因素指标,其长度探测至关重要。钢筋笼作为典型的铁磁性材料,其受地磁场环境磁化后会在钢筋笼附近产生磁场突变。本文基于钢筋笼磁化异常特性,根据磁荷理论,构建钢筋笼长度磁测井法探测磁场模型,开展了钢筋笼长度探测磁场模型参数化解析和工程桩测试试验研究。试验结果表明:钢筋笼磁场垂直分量和垂直分量梯度异常特征与钢筋笼底部位置密切相关,可作为判别钢筋笼长度依据;通过钢筋笼磁场模型参数化分析,得出探测孔桩孔间距对测试磁场异常特征影响较大,工程检测时需确保桩孔间距在1.0 m以内;通过钢筋笼磁场模型解析和工程桩试验验证,揭示磁异常特征产生原理和磁测井法工作机理。本文通过理论分析和工程桩试验研究,构建了钢筋笼磁场解析模型,为桩基钢筋笼长度探测技术应用提供了理论参考。The length of steel reinforcement cage is an important factor indicator that affects the pull-out,bending,seismic mechanical performance,and safety and stability of cast-in-place piles,and its length detection is crucial.As a typical ferromagnetic material,steel cage will exhibit a significant change in the magnetic field near the cage after being magnetized by the geomagnetic field environment.Based on the abnormal magnetization characteristics and magnetic charge theory,this paper constructs a magnetic field detection model for the length of steel cage using the magnetic well method.The test results show that the abnormal characteristics of the vertical component and gradient of the magnetic field in the steel cage are closely related to the position of the bottom of the steel cage,and can be used as a basis for determining the length of the steel cage.The parametric analysis of the magnetic field model of the reinforcing cage concluded that the spacing of the probe hole pile holes has a large influence on the anomalous characteristics of the tested magnetic field.When conducting engineering inspections,it is necessary to ensure that the distance between the pile holes is within 1.0 m.By analyzing the magnetic field model of the steel cage and verifying it through engineering pile tests,the principle of magnetic anomaly characteristics and the working mechanism of the magnetic well method are revealed.This paper constructs an analytical model for the magnetic field of steel cage through theoretical analysis and engineering pile test research,providing theoretical reference for the application of length detection technology for pile foundation steel cage.

关 键 词：灌注桩 承载性能 钢筋笼长度 磁测井法 磁荷理论 磁场模型 桩孔间距 

分 类 号：TU473.1[建筑科学—结构工程]