带肋薄壁方钢管混凝土柱温度场试验研究与分析

Experimental studies and FEM analysis of temperature distribution of thin-walled square concrete-filled steel tube with steel bar stiffeners

为研究带肋薄壁钢管混凝土柱在火灾下的温度分布,进行3根足尺带肋薄壁方钢管混凝土柱升温试验。建立方钢管混凝土柱温度场有限元模型,模型计算结果与实验结果符合较好。利用模型分析了典型的温度场分布规律,并研究了各参数对构件温度场的影响规律。结果表明:构件截面温度场在四面受火状态下呈双轴对称分布,且角部温度较高。加劲肋对构件温度场的影响仅限于焊接点附近,加劲肋间距和含钢率对构件整体温度场影响微小;截面边长、受火时间和受火方式是影响构件温度场的主要因素。

A test was conducted and a finite element model was established to study the temperature distribution in thin-walled square concrete-filled steel tube with steel bar stiffeners under standard fire. The reliability of the approach was validated by the good agreements between the theoretical results and the experimental data at elevated temperature. The effects of parameters on the temperature distribution of thin-walled square concrete-filled steel tube with steel bar stiffeners under standard fire were analyzed.Results show that under the standard fire exposure,the temperature field shows a distribution of biaxial symmetry. The effects of steel bar stiffeners on temperature distribution is limited to the field of near weld. Steel bar spacing and steel ratio have slight influence on temperature field of columns. Size of the cross section,fire exposure time and the surface varieties of fire exposure are the main factors influencing the temperature field of columns.