9522852 Gantry The use of non-metallic concrete reinforcements made of fiber- reinforced plastic composites will enhance the long-term durability of reinforced concrete structures subject to environmental exposure. Though plastic composite reinforcements do not corrode, they may not be thermally compatible with concrete. If the two materials prove to be thermally incompatible, the bond between them may be degraded by long-term exposure to temperature fluctuations. The transverse isotropy of composite reinforcements exacerbates considerations of thermal incompatibility. To quantify the influence of this potential thermal incompatibility and to verify manufacturer's claims regarding the thermal compatibility, it is planned to experimentally determine the longitudinal and transverse coefficient of thermal expansion of composite rebar. The potential for bond degradation due to thermal cycling will then be explored using simple pull-out tests of concrete/composite rebar specimens that have been thermally cycled. Finally, the effect of bursting stresses caused by transverse expansion of the composite reinforcement in concrete will be explored using beam specimens with varying levels of clear cover over the composite reinforcements.
