Tension Behavior of Bituminous Mixture Samples Reinforced by Fiberglass Geogrids in Different Directions

Abstract

This work aims at presenting a new analysis methodology for interface mechanical characterization based on axial tension test, as well as verifying the effect of the fiberglass geogrid presence on interface behavior. Tests were performed on cylindrical samples vertically cored from slabs having horizontal interfaces. In addition, this investigation aims at verifying the geogrid contribution in the tension resistance of cylindrical samples horizontally cored also having horizontal interfaces. Two different bilayered asphalt slabs were prepared to conduct the investigation: one reinforced and one unreinforced. Both are composed of the same bituminous mixture, compacted in two layers glued by emulsion tack coat made with 160/220 pen grade bitumen. Afitexinov produced the coated geocomposites used in the study, based on a knitted fiberglass geogrid of 100 kN/m tensile strength in both directions, associated with a polyester veil. The characterization was conducted through tension test at a controlled axial strain rate (2% per minute) and at two temperatures (19 and 40 °C). Two tests were performed for each temperature and each type of sample (vertically and horizontally cored) resulting in sixteen test results. The proposed methodology is successfully able to characterize the interface behavior subjected to axial tension loading. The differences in the observed results are related to the variation of the interface thickness with and without fiberglass geogrids. Concerning the horizontally cored samples, a slight increase in the tension resistance was observed for the reinforced samples at 40 °C. This difference could be associated with the fiberglass geogrid contribution.