High Friction Surface Treatment (HFST) is a surface treatment that can effectively improve the frictional characteristics of pavements and enhance the users' safety on the road. Among all existing applications of HFSTs, bauxite and oil-based epoxy resin are the most commonly used materials in the United States. However, bauxite and conventional epoxy resin are not cost-effective and provide limited preservation benefits to the pavement structure with existing distresses (e.g., top-down fatigue). In this study, the performance of a new and cost-effective HFST that uses waterborne epoxy, emulsified asphalt and corundum sand was investigated through a battery of laboratory tests. The performance of the innovative HFST was evaluated and compared with common HFSTs (copper slags and bauxites) used in USA with respect to three aspects: (i) skid resistance improvement before and after the treatment, (ii) durability to environmental effects (moisture induced damage and freeze-thaw cycles), and (iii) the effect of application on surfaces with existing top-down cracking. The results showed that the new HFST with waterborne epoxy and corundum was able to improve the skid resistance similar to or better than the conventional HFSTs. The deterioration rate on skid resistance of new HFST after freeze-thaw cycles and damage were found to be faster than bauxites but slower than copper slag. In addition, since corundum sand used in the low-cost HFST is much finer than either copper slags or bauxites and viscosity of waterborne epoxy is less than oil-based epoxy resin, the new HFST's material has the potential to fill the existing cracks with a width of 1.5±0.1 mm and relief the further propagation of the existing top-down cracks.
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