基于双侧窄角域摄影的沥青路表三维重构及构造特征分析

Reconstruction and analysis of asphalt pavement texture using bilateral narrow angle photography

为满足无人驾驶车辆快速获取路表构造的需求,建立了基于双侧窄角域摄影的沥青路表三维重构方法.对室内压实混合料和室外路面进行表面三维重构,将平均构造深度计算值与铺砂法、环绕摄影的构造深度值进行比较,验证所建重构方法的正确性.建立了构造标准差、单位面积上峰数、峰高标准差等构造评价新指标,并应用于AC-13、SMA-13和OGFC-13构造分析中.结果表明:双侧窄角域摄影重构方法能快速获取路表的三维点云,重建三维构造;基于该方法的构造深度计算值与铺砂法实测、环绕摄影重构的构造深度值相当,适用于室内压实混合料和室外实际路面;所建立的构造评价指标能从构造分布特征、胎/路接触应力集中度等角度为无人驾驶车辆提供完整的路表构造信息.

In order to meet the requirements of acquiring pavement texture for unmanned vehicles,a method for the reconstruction of three-dimensional(3D)pavement surface using the bilateral narrow angle photography is developed.To verify the effectiveness of the proposed reconstruction method,the surface of compacted asphalt mixture and asphalt pavement are reconstructed,and the mean texture depth(MTD)is calculated and compared to those from the methods of the sand patch and surrounding photography.The new indexes including the standard deviation(SD)of texture depth,peak number per unit area and SD of peak height are established and applied in the analysis of three types of asphalt mixture(i.e.AC-13,SMA-13,and OGFC-13).Results show that the 3D point cloud and texture of pavement surface can be reconstructed using the bilateral narrow angle photography.There is no obvious difference of measured MTD among the three methods of the sand patch,surrounding photography and bilateral narrow angle photography.The proposed method is not only suitable for compacted asphalt mixture in laboratory but also for asphalt pavement.The established indexes can provide complete texture information for unmanned vehicles including the distribution of texture depth and concentration of contact stress between pavement surface and vehicle tire.