Research on Radar Forward Modeling for Detecting Urban Road Subgrade Disease Based on Radar

With the accelerated urbanization process in China, the construction of urban roads has entered a rapid development stage. At the same time, the frequent occurrence of urban road collapse disasters has become an urgent problem that needs to be addressed. Ground-penetrating radar (GPR) is a continuous, fast, and non-contact electromagnetic wave detection technology with high-precision non-destructive testing as its core. Due to its fast data acquisition and high resolution, GPR has been widely applied in the detection of road diseases in urban areas. However, the application and research of GPR technology are still in the early stage, and there are many issues to be resolved in terms of detection and identification. In response to these problems, this study conducted in-depth research on urban road collapse and GPR technology, focusing on the analysis of collapse mechanisms in urban road subgrades and the forward simulation of collapse-related subgrade diseases. Based on the characteristics of urban road collapse, the study classified different types of collapse and investigated their causes to identify the formation mechanisms of corresponding collapse-related subgrade diseases. By analyzing the basic principles of the GPR forward simulation software gprMax, a general model of urban road subgrade was established with reasonable parameters. Through the forward simulation in gprMax, a large number of simulated results of subgrade diseases were obtained. The signal waveforms and GPR image features in the simulation results were analyzed. Based on this analysis, the features exhibited by various types of diseases in GPR images were summarized, and the factors influencing image features were analyzed. Finally, the study conducted an analysis and research on the interaction between diseases and underground structures such as underground pipelines, as well as the interaction between different diseases in GPR images.