泡沫混凝土路基病害地质雷达正演模拟研究

摘要

尝试将地质雷达运用于浙江某大桥工程泡沫混凝土路基质量测试,获得了泡沫混凝土雷达图像信号,并对其信号特征进行了分析,得到了泡沫混凝土路基结构情况;建立了理想条件下泡沫混凝土路基结构模型,采用基于时域有限差分法(FDTD)的GPRMax程序,通过MATLAB编程对泡沫混凝土路基疏松、脱空、分层等病害进行地质雷达正演模拟,得出路基病害在雷达图像上的典型特征信号;同时分析病害形状、大小对信号的影响以及之间的定量关系.本研究成果有助于对泡沫混凝土实测雷达图像的解读,为地质雷达在泡沫混凝土路基病害测试应用提供参考.%In this paper,the ground penetrating radar(GPR)is applied to the quality test of foamed concrete roadbed in a bridge project of Zhejiang province,and the GPR image signal of foamed concrete is obtained. The signal's characteristic is analyzed to get the structure of foamed concrete roadbed.The road model of foamed concrete roadbed under the ideal condition is established. The GPRMax software based on finite difference time domain method (FDTD)is used. The loose,void and layering diseases of foamed concrete in roadbed are forward simulated by MATLAB which conclude the typical characteristic signal of the roadbed diseases in the GPR image.The influence of different shapes and sizes in the diseases on signal are explored,and the quantitative relationship is also analyzed. We find the results of this study are conductive to understanding the GPR image of foamed concrete,and it will provide reference for the quality test of foamed concrete roadbed diseases by GPR.