Laser-based measuring method for mean joint faulting value of concrete pavement

To realize the critical assessment of concrete joint faulting, a laser-based 3D detection system (Laser-based Joint Faulting Meter, LJFM) was designed and a calculation method was proposed. The 3D information of joint faulting was obtained based on laser triangulation method. Automatic threshold determination method and mean joint faulting value calculation method were proposed based on the double peak characteristic of joint faulting 3D height histogram. To verify the precision and accuracy of the LJFM, indoor and field experiments were designed and conducted. Repeated experiments of simulated joint faulting in indoor experiment show that measurement results of the LJFM has lower coefficients of variation, better reproducibility and higher stability than that of the Level. In indoor and field experiments of different joint faulting, the coefficient of determination between the LJFM and the Level are 0.944 and 0.958 separately while the correlation coefficients between them are 0.9761and 0.979 (both significant at p < 0.05 level), respectively, indicating the good repeatability of the LJFM and the high correlation of the two methods. Experimental results indicate that measuring mean joint faulting value using LJFM has high stability and accuracy.