Experiment Study Of The Mechanical Properties Of SRC Columns-RC Beam Joints After Fire

Beacuse of multiple layers, large use of space, use composite, the security structure and especially the fire safety problem is very prominent in high-rise buildings.Building fire had emerged frequently fully demonstrated this point in recent years.Steel reinforced concrete structure is widely used in modern buildings, beacuse of its high carrying capacity and good seismic performance, and its fire resistance research is less, depth study of the mechanical properties after the fire is of great significance.This paper mainly studied hysteretic behavior of the the high-temperature steel reinforced concrete columns-reinforced concrete beam (hereinafter referred to as SRC column-RC beam) joints, specifically carried out work in the following aspects:(1)Conducted SRC column-RC beam joints fire experiments,and obtained the corresponding data of the temperature measurement points, and compared the junction temperature with the beam cross-section temperature, and obtained the temperature field distribution and the joints heat transfer rule of steel reinforced concrete frame.(2)Conducted a hysteretic behavior experimental of high temperature SRC column-RC beam joints, and inspect the undermining state and distribution of cracks in concrete joints.As can be seen, the high temperature will cause the concrete surface cracks,the high temperature SRC column-RC beam joints will be cracking, peeling, and slippage ahead of the specimens at room temperature。 (3)Obtained the hysteresis curve of the high-temperature SRC column-RC beam joints, and conduct comparative analysis of the specimen with the foundation specimens, and analyzed the differential impact of the skeleton curves, displacement ductility, bearing capacity degradation, energy dissipation capacity and the moment-conner of before and after fire。(4)Select the appropriate thermal parameters, using the finite element analysis software ABAQUS creating a temperature field type of the SRC column-RC beam joints to simulate the existing experimental, and compared simulation results and experimental data, and abtained the temperature change cloud of the section and joints, verifing the validity of the model.It provided a basis for future hysteretic behavior of the node finite element simulation.