This paper presents the results of
an experimental investigation into the influence of temperature on small scale
concrete specimens, strengthened with externally bonded Carbon Fiber Reinforced
Polymers (CFRP). Debonding of the CFRP, due to high shear stresses in the
concrete at the interface with the adhesive, governs the failure of these
specimens at room temperature. Temperature changes however will affect the bond
properties of the CFRP-adhesive-concrete joint, both due to the significant
difference in the Coefficient of Thermal Expansion (CTE) between concrete,
adhesive and CFRP and due to the change of the material properties with
increasing temperatures. Both effects can affect the load level at which
debonding occurs. Especially the adhesive shows a significant decrease in
strength and stiffness when the temperature reaches the glass transition
temperature (Tg).
To investigate the influence of temperature on the debonding of externally
bonded CFRP, two different test setups were used; a double-lap shear test setup
and a three point bending test setup. Test results have shown that a change in
temperature affected both the failure load and the type of failure, especially
when the Tg of the adhesive was reached.