Performance of Axially Restrained Hollow and Concrete Filled Oval Steel Columns Subjected to Hydrocarbon Fire
Performance of Axially Restrained Hollow and Concrete Filled Oval Steel Columns Subjected to Hydrocarbon Fire
复制标题
DOI：
10.1260/2040-2317.3.2.181
复制
发表时间：
2012-06
影响因子：
1
通讯作者：
F. Ali;A. Jeffers;N. Goodfellow;A. Nadjai;T. Scullion;J. Gardner
中科院分区：
文献类型：
--
作者：
F. Ali;A. Jeffers;N. Goodfellow;A. Nadjai;T. Scullion;J. Gardner
本文是世界上首次对轴心约束椭圆形截面钢管混凝土柱的火灾性能进行试验研究和验证理论研究的成果。试验方案包括9根2 0 0×10 0×8 mm椭圆形截面的空心柱和混凝土柱，其细长λ=51，并在严重碳氢化合物火灾曲线下进行试验。1800 mm的柱在极限强度的0.2、0.4和0.6的加载比下进行了试验。文中介绍了所获得的实验结果，包括测得的轴向和侧向位移、约束力和破坏时间。利用有限元方法建立了三维模型，并用试验结果进行了验证。通过使用随温度变化的热膨胀系数和EC3热参数，有限元模型与破坏温度、破坏模式、轴向位移和产生的轴向力的试验结果具有很好的一致性。利用验证后的有限元模型进行了一系列载荷水平和长细比参数的参数分析。研究表明，与低荷载比下的空心截面相比，填充混凝土截面具有更好的耐火性能。研究表明，施加轴向约束使柱的耐火性能在时间域上降低了约三分之一。研究还表明，荷载比与椭圆柱的长细之间存在非线性关系，荷载比对高长细柱的抗火性能影响较大。
This paper represents the outcomes of the first research in the world involving experimental and validated theoretical study to investigate the performance of axially restrained steel columns with hollow and concrete filled elliptical sections subjected to fire. The test programme involved 9 hollow and concrete filled columns with 200 × 100 × 8 mm oval section yielding a slenderness λ=51 and tested under the severe hydrocarbon fire curve. The 1800 mm columns were tested under loading ratios = 0.2, 0.4 and 0.6 of the ultimate strength. The paper presents the obtained experimental results including measured axial and lateral displacements, restraint forces and failure time. A three-dimensional model was built using the finite element method (FEM) and was validated using the obtained tests results. By using variable with temperature thermal expansion coefficient and the EC3 thermal parameters, the finite element model demonstrated an excellent agreement with test results of failure temperatures, failure modes, axial displacements and generated axial forces. The verified finite element model was used to conduct a parametric analysis involving a range of parameters of loading level and slenderness. The study has shown that the concrete filled sections have demonstrated an improved fire resistance when compared to the hollow sections under low loading ratios. The research indicates that imposing axial restraint has reduced the fire resistance of columns by approximately one third on the time domain. The study has also shown a non-linear relationship between the loading ratio and slenderness of elliptical columns and that the load ratio has more effect on fire resistance of columns with high slenderness.