论文部分内容阅读
对液体和热机械模型间的单向耦合过程进行数值研究,从而评估火灾条件下复合钢-混凝土结构的性能。分析的第一阶段包括使用三维的计算流体力学(CFD)来完成对火灾动力学的评估。火灾作用下构件的温度变化是分析的第二阶段,计算火灾的时间,获得计算流体力学的热通量,且材料的热性能随温度而变。最后,根据有限元方法(Vulcan方案)和欧洲规范1.2对钢板和混凝土包括应力-应变-温度关系的结构性能进行评估。所完成的三维有限元模型的结构模型涉及到对柱、梁和板局部和整体失效模式的识别。在非线性力学分析中对如膜和悬链效应这样的二阶效应进行解释说明。使用所提出的计算流体力学的有限元模型分析一个实际案例。分析结果验证了耦合三维流体热力学模型可成为目前防火设计分析的一部分,介绍了一种更实际和经济的防火设计方法。
A numerical study of the unidirectional coupling between liquid and thermomechanical models was conducted to evaluate the performance of composite steel-concrete structures under fire conditions. The first phase of the analysis included the use of three-dimensional computational fluid dynamics (CFD) to complete the assessment of fire dynamics. The temperature change of the component under fire is the second phase of the analysis, the time of fire is calculated, the heat flux of CFD is obtained, and the thermal properties of the material vary with the temperature. Finally, the structural properties of steel and concrete including stress-strain-temperature relationship were evaluated according to the Finite Element Method (Vulcan scheme) and European Specification 1.2. Finished structural models of the three-dimensional finite element model involve the identification of local and global failure modes of columns, beams and plates. Second-order effects such as film and catenary effects are explained in nonlinear mechanical analysis. A practical case is analyzed using the proposed finite element model of computational fluid dynamics. The analysis results verify that the coupled three-dimensional fluid thermodynamic model can be a part of the current fire protection design analysis, and a more practical and economical fire protection design method is introduced.