Research On Shear Behavior Of Prefabricated Concrete Interface After Elevated Temperature

Prefabricated structure is mainly a kind of concrete structure formed by prefabricated components through reliable connection.There is a fundamental difference between prefabricated structures and cast-in-place structures.The destruction of cast-in-situ structures mostly begins with the destruction of the components themselves.The destruction of prefabricated structures mostly starts at the connected parts.Therefore,the connection of components will directly determine the overall structure.reliability.The connection performance of prefabricated concrete interface after high temperature may be weakened or disappeared.However,the research on this aspect is still blank.Based on the above conditions,the prefabricated prefabricated concrete interface after high temperature is studied,and the ultimate load of the specimen after high temperature is studied.The properties of force,residual bearing capacity,interface stiffness,and failure mechanism were analyzed and studied.The finite element Abaqus software was used for simulation verification,and the recommended cohesion force parameter values available for practical fire resistance design were obtained.The main work is as follows:(1)Launch tests were conducted on 60 specimens with no rib interface,taking into account the effects of interface roughness,concrete strength,and temperature on shear strength.Obtain load-displacement curves and failure modes.Analysis of the ultimate load,interface stiffness,ductility and other properties.(2)Launch tests were conducted on 40 human hair cutting interfaces.A load-displacement curve is obtained.Compare the effects of artificial chiseling and grooved interface treatment methods.(3)Launch trials of 108 specimens with ribbed interfaces,taking into account the effects of interface roughness,stranding rate,and temperature.Obtain load-displacement curves and failure modes.The mathematical model is summed up through the load displacement curve and the formula is fitted.(4)The finite element software Abaqus was used to simulate the high temperature concrete interface,the cohesion force model was used to simulate the interface bonding,and the nonlinear spring Spring2 was used to simulate the bond between the steel and concrete interfaces.Through comparative analysis and verification,reference was made to the fire resistance design.Cohesion model parameter recommended values.