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Fiber-reinforced resin (FRR) plates are being incorporated into structural joints to correct thermal bridging issues to create more energy-efficient buildings. The purpose of this study was to evaluate the behaviors of simple shear and moment connections that include FRR thermal barrier plates under service-loading conditions. Tests included two thicknesses and two grades of barrier plate. The shear connection tests showed that the coefficient of friction between steel and an as-received FRR plate was significantly lower than that of steel on steel. However, roughening the FRR plates by blasting with aluminum oxide increased the coefficient to nearly the same as or greater than steel on steel. In moment connections the presence of thermal barrier plates increased the joint rotation at the connection. A 25-mm (1-in.) thermal barrier plate increased the joint rotation by 10% compared to a joint without the barrier plate. The increase was 20% for a 50-mm (2-in.) plate. The thermal barrier plates did not affect the dynamic response of the test fixture at structurally important frequencies. [ABSTRACT FROM AUTHOR]

Externally applied composite reinforcement can be used to provide additional strength or ductility to concrete members as part of a seismic retrofit or repair to a structure, but the composite reinforcement may be exposed to elevated temperatures. In this study, concrete cylinders were wrapped with a composite reinforcing system, exposed to a range of elevated temperatures and allowed to cool. Subsequent compression testing of the cooled cylinders indicated there was no statistically significant loss of strength until the treatment temperature was more than 30°C above the glass transition temperature of the epoxy. Additionally, the predominant mode of failure of the composite system changed from hoop split to seam debonding at the same temperature. This study also examined the role of a fireprotective coating that forestalled the onset of the transition of failure modes by almost 30°C. [ABSTRACT FROM AUTHOR]