Surface Friction on Longitudinally Tined Concrete Pavements: New Findings from Field Testing and Finite-Element Analysis Simulation

This paper presents new findings on the surface friction performance of longitudinally tined concrete pavements from field testing and finite element analysis (FEA) simulation. Field testing showed that the tire footprint on the tined surface consisted of many small contact zones with different shapes and areas. The distribution of contact pressure was not uniform on the tined pavement surface. The surface friction on longitudinally tined pavement was much less than those on both transversely and diagonally tined pavements. The friction decreasing rate on longitudinally tined pavements was larger than those on transversely tined and longitudinally broomed pavements. Longitudinally tined pavements did not outdo conventional pavements in long term surface friction. The FEA simulation analysis showed that the tire footprints on both smooth and longitudinally tined pavements were different in shape. The contact pressures were not uniformly distributed in the contact zones on these two pavements. On longitudinally tined pavement, the largest contact pressure occurred at the footprint center. For 3 mm wide, 3 mm deep longitudinal tining, tine spacing of 15 mm or 35 mm underwent larger viscous dissipations than 25 mm tine spacing and therefore might provide larger hysteresis friction. Increasing tine width or tine depth appropriately can enhance hysteresis friction. Increasing the tine width may be more effective in improving hysteresis friction than increasing the tine depth.