Study on water permeability, shear and pull-off performance of waterproof bonding layer for highway bridge

The performance of waterproof bonding layer directly effects the durability of the highway bridge. Water permeability, shear strength and tension strength are three main indicators evaluating the waterproof bonding layer. In this research, three waterproof bonding materials including SBS modified asphalt, SBR modified asphalt emulsion and second order reaction waterproof material were selected. The water permeability, shear strength and pull-off strength were tested. The effect of different temperature and different contents were analyzed. Results show that: the water permeability resistance of waterproof bonding layer ranked as follows: SBS modified asphalt > Second order reaction waterproof material > SBR modified asphalt emulsion. Compared to SBR modified asphalt emulsion and second order reaction waterproof material, SBS modified asphalt has a better shear resistance. Three waterproof materials used in this research all have temperature sensitivity. Their shear strength and tension strength decrease dramatically with temperature increasing. Keywords: Waterproof bonding layer, Highway bridge, Water permeability, Shear performance, Pull-off performance