Evaluation of effective parameters and model development for pull out strength of geocomposite in asphalt

One of the maintenance methods for cracked pavements is application of overlay on its surface. In this situation the overlay is open to the cracks with the shape of previous cracks. One of the most important methods for prevention of these cracks (that named reflective crack) is using geosynthetics. The bonding of geosynthetic between asphaltic layers has noticeable importance when the geosynthetic is used for reinforcement. Pull out is a common test in order to find the amount of geosynthetic- soil bonding, though this test is not common for geosynthetic- asphalt bonding. In this research a pull out test device has been developed in Amirkabir University of technology and used to evaluate the bonding of geosynthetic-asphalt with different geosynthetic grid sizes. Effect of three important parameters on pull- out test results has been evaluated and compared. Based on the findings of this research the most effective parameter is temperature. The next effective parameter is tack coat application rate. Based on the ANOVA the conflict between parameters has been studied. The most important conflict was belonging to the conflict of temperature and the tack coat application rate. Based on the mentioned studies a model has been developed for maximum bonding and temperature and tack coat application rate.