Fire Resistance Of Steel Reinforced Concrete Columns Under Large Eccentric Load Subjected To 3-Face Heating

Steel reinforced concrete (SRC) columns are being widely used in engineering structures in recent years for their distinct economic benefit and structural advantages, such as high load bearing capacity, excellent earthquake resistance qualities. The fire resistance capabilities of structures are attracting more and more attention at the same time. However, the current researches on fire resistance capabilities of SRC columns still focus on 4-face heating. Few researches have been conducted on SRC columns subjected to 1,2,3-face heating. In this paper, an experiment on fire resistance of SRC columns under lager eccentric load subjected to 3-face heating was done and analysis was undertaken on the factors of fire resistance, subsequently the approach of calculating the duration of the fire resistance of SRC columns is generated for engineering practice.The main contents are as follow:(1) Thermal properties, mechanical performances of steel and concrete under high temperature are summarized and analyzed after reading a lot of documents. Base on these works, the right calculation model for this paper was determined.(2) Tests on the fire resistance of two SRC columns under lager eccentric load subjected 3-face heating were done. Experimental phenomenon was recorded, finally the durations of fire resistance and time-deformation curves were got.(3) A nonlinear finite element analysis (FEA) modeling was developed to analyze the fire resistance of SRC columns subjected to 3-face heating by using the software of ABAQUS 6.9. The analysis results show generally reasonable agreement with the test results.(4) Parametric analysis on duration of fire resistance of SRC column was done, such as load ratio, eccentric ratio, steel ratio, section dimension, slenderness ratio.(5) Formula of calculating the duration of fire resistance was generated from the point of mechanical behavior. Base on analyzing the influence on the fire resistance of these parameters, some advises were given in fire resistance design.