Evaluating and Modelling the Effect of Carbon Fiber Grid Reinforcement in a Model Asphalt Pavement

ABSTRACT

Laboratory and modeling results on a special type of carbon fiber grid placed at different depth in model asphalt pavements are presented. The purpose was to obtain design information regarding the position of the grid to reach optimum effect. Two completely differenttypes of asphalt pavements were investigated: asphalt concrete and mastic asphalt. Depend on the different application range of these materials, the test program was slightly different in each case. In case of asphalt concrete, special focus was devoted to the question of rutting performance with the Model Mobile Load Simulator MMLS where the asphalt layer was placed on a rubber pad foundation in order to increase bending effects. Test results are discussed and compared with dynamic FE modeling using ABAQUS. In addition, interlayer shear properties were investigated with the layer parallel direct shear test LPDS based on the Leutner device. The evaluation of the complex modulus in the coaxial shear test CAST developed by EMPA is also presented. In case of mastic asphalt, rutting and cracking resistance were considered varying the mesh width of the grid. Here, MMLS and LCPC rutting tests were performed. As for cracking resistance, the influence on bottom up cracking regarding bridge deck application at freezing temperature was evaluated with a special mechanical stretching bench that enabled to study a model system with a mastic asphalt placed on a bituminous waterproofing membrane