Post-fire serviceability and residual strength of composite post-tensioned concrete T-beams

Abstract In this study, the response of ten composite post-tensioned concrete beams topped by a reinforced deck with adequate reinforcing shear connectors is investigated. Depending on compressive strength slab (20, 30, and 40 MPa), are grouped into three categories. Seven these exposed to fire attack 700 800 °C temperature simultaneously or without presence uniformly distributed sustained static loading. After cooling back ambient temperature, loaded up failure, using force control module, monotonic loading in four-point-bending setup two symmetrical concentrated loads applied middle third effective span. The objectives study include investigating behavior prestressed under after exposure direct flame, as well finding their residual load-carrying capacity. Tests demonstrate significant deteriorations caused high temperatures associated increase member’s camber. midspan camber heating reached approximately 200%. On other hand, 1-h steady-state test specimens led reduce capacity heat-deteriorated 45% 54%, respectively.