Research On 3D Radar Detection Technology For Asphalt Pavement Disease

Since the reform and opening up,China’s highway construction has made remarkable achievements,while China’s highway maintenance tasks are increasingly onerous.Many highway diseases of different scope and degree appear soon after opening to traffic,such as holes,cracks,boiling,rutting,subsidence,pits and other diseases.The traditional early disease excavation detection method is more destructive to the expressway.Ground Penetrating Radar(GPR),as an efficient and fast non-destructive detection tool,has been widely used in non-destructive testing of water conservancy,road and tunnel lamp infrastructure projects.At present,the non-destructive testing technology of GPR maps are two-dimensional,which can not comprehensively detect the location and extent of early diseases of highway.In this paper,a new type of frequency-stepped three-dimensional(3D)GPR is used for nondestructive detection of early highway diseases,and the accuracy of the new type of Geo Scope? 3D GPR nondestructive detection technology is verified by comparing with the forward simulation of 3D finite difference time domain(FDTD).The main research contents and conclusions are as follows:1.This paper studies the early highway hidden disease detection technology based on Geo Scope? 3D GPR.It is aimed at the multi-receiving characteristics of the frequency stepped three-dimensional ground penetrating radar antenna array,the fast 3D image processing of the 3D structure,and the analysis of different types of roads.The characteristics of the 3D radar map of hidden diseases provide a theoretical basis for the analysis of new 3D radar data and disease identification.2.Based on the 3D time-domain finite-difference method(FDTD),a forward modeling model of ground penetrating radar electromagnetic waves propagating in three-dimensional consumable medium is constructed.The 3D GPR detection of the early highway disease such as highway subgrade,road cracks and soil foundation is simulated,which provides a basis for explaining the three-dimensional ground penetrating radar profile of the early highway disease.3.The stepped-frequency 3D GPR is used to detect the test section of a highway,and the deep disease of transverse crack position in all pavement of test sectionare analyzed,and the results are compared with the Falling Weight Deflectometer test.The results show that the 3D GPR can not only evaluate the road deep diseases,but also detect the depth and direction of the cracks,which can provide accurate detection basis for road maintenance.The results of this paper are helpful to determine the early diseases of Expressway without damage in the early stage,to the application of non-destructive testing technology in the disease detection of expressway,to enhance the service life of Expressway in our country and to ensure the safety of driving,and to promote the development of non-destructive testing and maintenance technology of Expressway in our country.