一种应用于结构抗火模拟的新型板单元  

A New Type of Plate Element Applied to Fire-resistance Simulation of Structure

作　　者：何中宝[1] 丁勇[1] 

机构地区：[1]宁波大学结构工程系,浙江宁波315211

出　　处：《常州工学院学报》2009年第5期8-13,共6页Journal of Changzhou Institute of Technology

基　　金：浙江省自然科学基金(Y607563);浙江省教育厅科研计划(20070959);宁波市自然科学基金(2009A610157)

摘　　要：局部火灾下,钢框架结构中直接受火的楼板在辐射和对流换热作用下产生的热变形是值得关注的。为了准确地预测这种变形,推导了一种能同时考虑板厚平均温度和温度梯度的板单元有限元格式,用以分析受火楼板的热力学响应。假设该种板单元温度沿厚度方向呈线性分布,把辐射和对流换热条件以热量的形式代入传热学场方程,并假设热量沿厚度方向也呈线性分布。对该种板单元瞬态温度场和热变形的实例计算表明,数值解和理论解符合得较好,同时发现是否考虑板厚温差导致的热弯曲对该种板单元的热变形分析影响很大。This paper demonstrates the numerical simulation effectiveness on thermodynamical response of the new element. Thermal deformation of ablaze floors in steel frame structures under localized fire conditions caused by thermal radiation and thermal convection deserves attention. In order to predict the deformation accurately, a kind of finite element scheme is derived to analyze mechanical behavior of Fired floors. By this scheme, not only the average temperature but also the temperature gradient along the thickness direction can be considered. Temperature distribution is assumed as linear along thickness direction. Thermal radiation and thermal convection were expressed in heat transfer field equation in form of heat, and the heat distribution is supposed to be linear along thickness direction. Transient temperature and thermal deformation of this element is practically calculated, which proves that numerical solutions accord with theoretical solutions well. The calculation also indicates that considering the bending load caused by temperature difference along thick- ness direction or not has great influence on thermal deformation of such element.

关 键 词：热变形 温度梯度 有限元格式 线性分布 瞬态温度场 数值模拟 

分 类 号：TU352.5[建筑科学—结构工程]