Study On Evaluation Index And Method Of Asphalt Pavement Construction Quality Uniformity Based On Ground Penetrating Radar

The road service life of our country is generally low,the reason is that the early damage phenomenon of the pavement frequently occurs.And the main reason for the early damage of the pavement is the nonuniform quality of the asphalt pavement construction,which leads to the deviation from the design value of the actual value of the pavement,so the pavement can not reach the expected effect.The existing highway engineering specifications have not yet established acknowledged and effective evaluation indicator and method for asphalt pavement uniformity.This article is based on ground penetrating radar(GPR),combined with nonnuclear density meter,to detect and evaluate the uniformity of asphalt pavement construction quality.The evaluation index and grading standard of asphalt pavement structure uniformity and material uniformity are put forward respectively,so as to provide a new idea for the establishment of quality uniformity control and evaluation system for asphalt pavement construction.The paper starts from the composition of GPR system,and analyzes the working principle of GPR detection in detail.The typical pavement reflection waveform of GPR are analyzed and summarized.Considering the requirements of ground penetrating radar used in this paper and the existing test conditions,the inside detection system for ground penetrating radar is built.The uniformity of asphalt pavement is subdivided into structure uniformity and material uniformity.Through the analysis of structure uniformity and material uniformity,the thickness and density are selected to evaluate them respectively.The index deviation rate is used as the grading standard of uniformity,and the specific grade limit is determined.The inside molding samples are tested and evaluated by the GPR inside detection system,which verifies the feasibility of the inside detection system.When the standard value of pavement thickness is known,the dielectric constant mean method is proposed to calibrate the actual dielectric constant of the pavement,and the feasibility and accuracy of the calibration method are verified.The GPR inside detection system is applied to test and evaluate the outside trial pavement sections.The concept of weighted nonuniform rate is introduced,and order relation analysis is applied to assign weights to the nonuniform grade of pavement.The structure uniformity and material uniformity of the detection lines of each detection section are evaluated quantitatively,and the overall uniformity of the three detection sections is analyzed and evaluated,which verified the feasibility of the evaluation method.