Investigations on interlayer shear strength characteristics of geosynthetic-reinforced asphalt overlay sections at Salvador International Airport
Natália S. Correia, Tiago R. Souza, Matheus Pena da Silva e Silva, V. Vinay Kumar
Abstract
This study aims at evaluating the interface shear strength characteristics of full-scale geosynthetic-reinforced asphalt overlay sections constructed at Salvador International Airport, Brazil. Specifically, 24 experimental sections including 5 different geosynthetic reinforcements and no geosynthetic reinforcement (control) with 4 different tack application rates were considered in the study. Multiple asphalt cores of 150 mm diameter were then extracted and tested in the laboratory using Leutner shear tester. Results demonstrated that the interface shear strength varied depending on the geosynthetic and tack coat rates, and mostly increased with increasing tack application rates. An interaction between tack application rates and geosynthetic characteristics was observed, which was highly influenced by the geosynthetic asphalt retention capacity. Overall, it can be inferred that the geogrid aperture size, mass per unit area of nonwoven geotextile backing, and geosynthetic tensile stiffness influenced the interface shear strength characteristics of geosynthetic-reinforced asphalt overlay.