Fire Resistance of Precast Concrete Sandwich Cladding Panels with FRP Connectors

To investigate the influence of the inorganic insulation mortar layer on the fire resistance of precast concrete sandwich panels（PCSPs） with fiber-reinforced polymer （FRP） connectors， a coupled temperature-displacement finite element model was developed using the finite element software ABAQUS by considering the effects of high temperature on concrete， rebars， and FRP materials. Finite element analyses were conducted under standard fire conditions， and the results were validated against fire resistance tests on two PCSPs with FRP connectors. Subsequently， parametric analyses were performed to examine the effects of out-of-plane loading and fire exposure duration. The results showed that the inorganic mortar increased thermal resistance and flexural stiffness but reduced heat convection within the panel. The FRP connectors were slightly damaged while still capable of providing shear capacity， and the glass transition temperature was found to be a conservative indicator of their failure. Although out-of-plane loading led to larger panel deflections， it had no appreciable effect on the temperature distribution. Compared to the 60-minute fire exposure， the FRP connectors were more prone to anchorage failure after 180 minutes of fire exposure.