Residual performance of concrete–adhesive interface at elevated temperatures. (15th February 2016)

• Record Type: Journal Article
• Authors: Namrou, Abdul R.; Kim, Yail J.
• Is Part Of: Construction & building materials. Volume 105(2016)
• Page Start: 113
• Page End: 122
• Publication Date: 2016-02-15
• Subjects: Bond -- Degradation -- Elevated temperature -- Interface -- Performance-based design -- Thermal; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2015.12.014
• Languages: English
• ISSNs: 0950-0618

Abstract

Highlights: The interfacial behavior of adhesive–concrete members is examined when exposed to elevated temperatures. Residual thermal-responses are characterized at material- and structure-levels. Performance-based design of concrete–adhesive interface subjected to thermal loading is proposed. Abstract: This paper presents a two-phase experimental program to evaluate the performance of concrete–adhesive interface subjected to thermally-induced distress, including material- and interface-level investigations. Elevated temperatures ranging from 25 °C to 200 °C are applied to three adhesive types (i.e., low viscosity, high viscosity, and high temperature epoxies). The residual thermal behavior of these epoxies and corresponding concrete–adhesive interface is characterized by various test methods such as dynamic mechanical analysis (ASTMD7028 ), dynamic elastic modulus test (ASTMC215 ), and bending test (ASTMC78 ). With an increasing temperature, the resonant frequency and dynamic modulus of the concrete–adhesive interface decrease due to the physical softening of the adhesive layer. Strength recovery is observed with a change in adhesive-morphology when the applied thermal load disappears, while such an effect is not pronounced for the high temperature adhesive. Thermomechanical observations indicate that the deformability and stiffness-softening of the concrete–adhesive interface tend to augment at elevated temperatures, and the failure of the interface is controlled by material cohesion rather than adhesion. Technical recommendations are proposed towards the performance-based design of concrete–adhesive interface subjected to temperature load.