Title:
Heat Cycling of Epoxy Mortar-Repaired Beams
Author(s):
A. I. Abu-Tair, E. Burley, and S. R. Rigden
Publication:
Materials Journal
Volume:
94
Issue:
2
Appears on pages(s):
129-133
Keywords:
beams (columns); epoxy; heat cycling; mortars (materials;
temperatures;
DOI:
10.14359/293
Date:
3/1/1997
Abstract:
The use of epoxy patch repair materials has gained in popularity in both temperate and hot climates over the past two decades. Temperatures in hot climates can vary significantly over a 24 hr period. In the Gulf region daytime temperatures in the shade can commonly exceed 50 C (122 F), with nighttime temperatures dropping to single figures. In such climates the sun usually shines for long periods, raising temperatures of surfaces in direct sunlight to even higher values. To investigate this, five reinforced concrete beams with a preformed fault repaired with lightweight epoxy render (LWER) were subjected to 1000 heat cycles prior to being tested statically. Pulloff bond tests were then carried out on these beams to investigate the effect of heat cycling on the bond strength between the LWER and concrete substrate. The heat cycling of the epoxy-repaired beam showed that the bond between the repair material and the concrete substrate remained intact. The cycling, however, did cause the epoxy render to crack. These cracks were similar to shrinkage cracks and extended into the beam section to the shear reinforcement.