Abstract: To examine the shear behavior of the interface between concrete and fiber-reinforced high-strength grout after high-temperature exposures, Z-type double shear test specimens were designed and tested via ther‐ mal and push-out shear experiments. The test parameters include temperatures of 20, 100, 300, 500, and 600 ℃, interface roughness and grout strength. The results show that the shear resistance of the interface decreases with the increase in temperature. By improving the interface roughness, the interfacial shear capacity was enhanced, and the efficiency of the enhancement remained relatively stable as the temperature increased. Moreover, the shear resistance of the interface was found to be positively correlated with the strength of the grout.

Key words: post-elevated-temperature, concrete-CGM interface, shear resistance, interface roughness