Multi-dimensional Index Detection of Potholes Based on 3D Laser Technology

Abstract:

In order to automatically and accurately achieve multi-dimensional indexes such as depth, area and volume of the asphalt pavement pothole, the advanced three-dimensional line laser technology was used to scan indoor potholes with different sizes. The laser point cloud data collected was processed using the triangulated irregular network(TIN) plane interpolation method by Matlab software and was used to reconstruct the three-dimensional pothole model. Combined with contour extraction method, the pothole border was identified and multidimensional indexes of pothole were automatically calculated. The relative error of different pothole multi-dimensional indexes was compared and the effect of laser’s longitudinal spacing on relative error was studied. The results show that the maximum relative error of the pothole depth, area and volume are 3.96%, 4.58% and 4.74%, respectively. The relative error of pothole multi-dimensional index decreases with the increases of pothole size. When laser’s longitudinal spacing increases from 5 mm to 20 mm, the relative error of pothole multi-dimensional index increases by degrees. The maximum relative error of pothole depth, area and volume are 4.65%, 6.32% and 7.17%, respectively, when spacing is 5 mm. The relative error of pothole multi-dimensional indexes increases significantly when spacing becomes larger than 5 mm. Therefore, to insure the accuracy of multi-dimensional index detection, it is suggested that laser’s longitudinal spacing is less than 5 mm. The method of pothole multi-dimensional index accurately provides foundation for the pavement structural layers identification of damage distribution, evaluation of distress severity and estimation of materials rehabilitation.