Mechanical Properties And Failure Mode Of Reinforced RPC Simply Supported Beams Under And After Fire

As a revolutionary new composite material,reactive powder concrete(RPC)has been widely used in engineering field for its super high strength,well toughness,durability and volume stability.Fire is one of the most frequent and harmful disasters.It is necessary to study the mechanical properties of RPC materials and structural members under and after fire.In this paper,the mechanical properties of four reinforced RPC simply supported beams under fire and after fire are analyzed as follows.(1)Fire test were carried out on reinforced RPC simply supported beams under constant load,and the influence of test parameters such as reinforcement ratio and load level was investigated.The mechanical behavior and deformation law of reinforced RPC simply supported beams under high temperature were observed.Meanwhile,the measured results of temperature field distribution and mid span displacement-time curve at different positions of the test beams were obtained.(2)Finite element analysis software ABAQUS was used to simulate the mechanical properties of reinforced RPC simple supported beams with fire duration of 135 min.The simulation results of temperature field distribution and mid span displacement-time curve under fire were obtained,and compared with the measured results of fire test to confirm the accuracy of the conclusions.(3)The bending test of reinforced RPC simply supported beams after fire was completed.The residual bearing capacity of normal section,the crack development pattern and the load-mid span displacement curve were obtained.The test results were compared with the mechanical properties at room temperature.The reliable research results of this paper can provide reference for damage identification,post disaster reinforcement and repair of RPC structural members in fire to improve their safety.