Application Research On PFWD Rapid Testing Evaluation Of Compaction Quality For Asphalt Pavement

In order to solve the problems such as low efficiency,poor representativeness and damage to the structure layer of the compaction quality testing technology of the asphalt pavement,relying on the road construction project in Yaohai District,in Hefei City,Anhui Province,the application research of PFWD rapid testing evaluation of compaction quality for asphalt pavement is carried out,hoping to provide the scientific basis for the rapid nondestructive testing and evaluating the compaction quality and the bearing capacity of the structure layer in the asphalt pavement construction process.1)By analyzing the performance parameters,working theory and reliability of PFWD,the corresponding testing technical regulation and data processing methods are proposed.Meanwhile,its load sensors and displacement sensors have high stability and can be used for quality monitoring and acceptance of asphalt pavement construction site.According to the comparison between PFWD dynamic and static backcalculation methods,the results show that compared with the static back calculation,the dynamic back calculation method can calculate the density while calculating the modulus,which has the advantages that other detection methods do not have.2)The raw material performance test shows that the performance indexes of asphalt,coarse and fine aggregate meet the technical requirements and can be used to prepare asphalt mixture.The standard density of the asphalt mixture was determined by the Marshal stablity test and used to control its compaction characteristics.At the same time,the indoor test was carried out by using PFWD,and the inverse modulus and density were obtained.Through the size and temperature correction of the modulus backcalculation result,combined with the compaction degree of the asphalt mixture test piece,the power function relationship between the two was established,which can provide guidance for on-site asphalt surface lamination quality control.3)Combined with on-site construction,PFWD was used to quickly test and evaluate the compaction quality of various structural layers of asphalt pavement.The results of dynamic backcalculation of asphalt surface at different temperatures and cement stabilized macadam base layer at different ages were analyzed.The power function relationship between PFWD inverse modulus and compaction degree is proposed.Based on thiss the modulus control standard of asphalt surface and semi-rigid base construction process is proposed.The results show that the PFWD modulus can be used to quickly detect and evaluate the compaction quality of asphalt pavement.4)By comparing the PFWD test and the BB test on the asphalt surface of Xiangcheng Road in Yaohai District,the correlation between the two is analyzed,and the empirical formula between modulus and deflection is established,and the quality acceptance criteria based on PFWD modulus is proposed.Based on the application of engineering,the applicability and reliability of PFWD rapid testing evaluation technology in asphalt pavement construction acceptance are verified.In summary,this study provides a reference for the rapid detection and evaluation technology of asphalt pavement compaction quality,with good theoretical and practical significance and engineering application value.