Research On Detection Technology Of Tunnel Secondary Lining Disease Based On GPRMAX

With the continuous development of ground penetrating radar detection technology,it is an urgent problem to be solved by field workers to analyze the practical significance of radar imaging representative,find out the reasonable and feasible characteristics of distinguishing different diseases of radar echoes,and identify and judge diseases from radar images.In order to provide field staff with a comparison case of ground penetrating radar image analysis,the article analyzes the direction of tunnel disease research at home and abroad at present,and classifies and contrasts the images of different diseases under different excitation wave sources,and introduces the geological radar pair in detail.Image feedback of different diseases to different frequency sources during tunnel lining detection.The echo images in the GPRmax software were used to simulate the holes,cracks,ribs,water seepage and voids in the tunnel lining,and the corresponding relationship between the echo images and the disease was analyzed.The radar wave images of various cavity defects under simulation software are analyzed,and the correspondence between the excitation source frequency and the disease resolution on the radar echo is found.The difference of radar echoes when different positions on both sides of the lining are simultaneously cracked is analyzed.Summarize the simultaneous cracking on both sides,the degree of mutual interference of echoes and the law of interference.The imaging characteristics of single and double row steel bars are analyzed under the condition of lack of reinforcement in single and double row steel bars under different reinforced bars model.The law of interference between upper and lower rows of steel bars and the frequency of excitation wave source when double row reinforced steel bars are missing are summarized.Imaging trends with regular single row rebar models.The relationship between the imaging law of radar wave source and the type of water body at various frequencies under the water seepage disease is simulated;and the width of water seepage crack and the law of radar echo image.Using the results of the void model,the identification,determination and analysis methods of radar for the void between concrete lining and surrounding rock are summarized.Based on this,the radar images actually scanned at the scene were analyzed,and the simulation results were compared with the actual situation on site.The differences between the current methods for analyzing radar images and software simulations were verified.