Experimental Study on Surface Steel-Reinforcement for Asphalt Pavements

Abstract

The continuous increase of the number of heavy trucks with excessive axle load requires the implementation of new technologies, prolonging the longevity of road pavement. Therefore, Reinforcement grids have recently come into use in pavements in order to retard the distresses in the asphalt surface layers. The main objective of this research is to investigate the improvement of steel mesh used as reinforcement interlayer in asphalt layers to pavement performance through laboratory tests. Beams and slabs specimens of asphalt concrete mix are prepared, and tested with fatigue life and wheel tracking tests. The analysis of test results show that, the absence of reinforcement steel-mesh in Asphalt sample produces an improvement to the number of cycles and deformation rate for reinforced samples over the equivalent unreinforced samples, and the difference is significant at highest temperatures. The bottom location of steel mesh (bottom of wearing course layer) gives minimum deformation and maximum number of cycles to failure as compared with others locations of embedded grid. Depending on the ability of grids to reduce the development and growth of fatigue cracks; steel meshes can be used in asphalt concrete layers over weak layers or soft subgrade. Using steel grids in areas subjected to high shear stress levels such as at intersections, sharp corners and/or steep grades, will reduce the development of permanent deformation.