A new method of interlayer shear performance evaluation for permeable composite pavement (PCP) in laboratory

Abstract

Permeable composite pavement (PCP) has been increasingly applied for road design and construction. However, interlayer shear resistance is still a challenge for the road performance improvement of PCP. This paper presents a new method of interlayer shear performance evaluation for PCP with a self-made molding device and shear clamp. PCP test slabs are made in two ways, the porous asphalt mixture + impermeable and + permeable concrete layer, named PAIC and PAPC, respectively. The interlayer shear test of PCP slab specimens is conducted under different bonding material types, dosage, temperature, and interlayer contact interface morphology. The results indicate that: (1) The type and amount of bonding materials influence the interlayer shear performance of PCP slabs. The stronger the bonding property of the interlayer material, the greater the interlayer shear strength (ISS) of the PCP. There is the best amount of the same material as the interlayer bonding material. The optimum dosage of styrene-butadiene-styrene (SBS), matrix, and spraying cationic emulsified (PCR short in Chinese) asphalt on the PAIC board is 0.8, 0.6, and 0.4 L/m2, respectively. However, the optimal amount for each bonding of the PAPC slab is 0.6 L/m2. (2) The temperature has a great influence on the ISS of the permeable composite slab due to asphalt being a temperature-sensitive material. For the two slabs, the ISS decreases with the increase in temperature, and even the ISS at 5 °C is 10 times that at 50 °C. (3) The interface morphology of interlayer contact affects the performance of ISS. For PAPC, the contact interface between the two materials is rougher, and the high friction between layers leads to the larger ISS. PAPC's ISS is at least twice that of PAIC. (4) A new method of interlayer shear performance evaluation for the optimization design and application of PCP has been proposed in the final. The method includes material design, specimen making, testing, and quick evaluation. This method has the potential to contribute to the development of PCP tests in the laboratory.