中空夹层钢管混凝土短柱的耐火极限

Fire Resistance Limit of Concrete Filled Double Skin Steel Tubular Short Column

为了研究中空夹层钢管混凝土短柱的耐火极限,选择合适的钢材与核心混凝土的热工参数和本构模型,通过有限元软件ABAQUS剖析中空夹层钢管混凝土短柱在ISO-834标准升温曲线作用下的温度传递形式及顺序热-力耦合后构件耐火极限的变化情况,并与已有试验进行验证,结果吻合较好。分析了截面形式、空心率、载荷比和核心混凝土抗压强度等级等4个参数对中空夹层钢管混凝土短柱耐火极限的影响规律。研究表明:载荷比是影响中空夹层钢管混凝土短柱耐火极限的主要参数;截面形式和空心率对中空夹层钢管混凝土短柱耐火极限的影响较大;核心混凝土抗压强度等级对中空夹层钢管混凝土短柱耐火极限的影响不大。

In order to study the fire resistance of concrete filled double skin steel tubular short columns,appropriate thermal parameters and constitutive models of steel and core concrete were selected.The temperature transfer form of concrete filled double skin steel tubular short columns under the action of ISO-834 standard temperature rise curve and the change of fire resistance of components after sequential thermal mechanical coupling were analyzed by finite element software ABAQUS,The results were in good agreement with the existing tests.The parameters of section form,void ratio,load ratio and compressive strength grade of core concrete on the fire resistance of concrete filled double skin steel tubular short columns were analyzed.The research shows that the load ratio is the main parameter affecting the fire resistance of concrete filled double skin steel tubular short columns.The section form and void ratio have a great influence on the fire resistance of concrete filled double skin steel tubular short columns,and the compressive strength grade of core concrete has little effect on the fire resistance of concrete filled double skin steel tubular short columns.