Title: Bonding Shear Strength of Adhesives between Precast Concrete Elements
Author(s): M. Ali, S. Kurihara, and S. Matsui
Publication: Symposium Paper
Appears on pages(s): 551-570
Keywords: bond; precast concrete; shear strength; torque viscometer
An important factor for the success of repair works in concrete structures is to realize sufficient bonding between the repair material and the substrate. Nowadays there are many types of repair material available in the market with improved strength, adhesion, waterproofing and durability properties. There is a need to study the interfacial properties of these repair materials especially in-situ because these properties depend very much on method of placing, curing and environment condition etc. The authors developed a new testing method called the torque test to measure bonding shear strength by twisting concrete cylinder cores. Since concrete is weaker in tension than in shear, slant tension failure often occurred and pure torsional failure could not be achieved. The data from this type of failure are considered the minimum bonding shear strength. To prevent this type of failure, the top concrete cylinder is enclosed in steel pipe. The experimental parameters are the adhesives between two concrete such as epoxy resin, polymer modified cement mortar and cement mortar. The influence of surface roughness of concrete substrate on bonding strength is also investigated. A relationship between bonding shear strength and bonding tensile strength is obtained.