摘要
钢材在高温和荷载作用下产生明显的蠕变变形,从而对钢结构在火灾下的变形和受力性能产生较大的影响。为了研究高温蠕变对高强度Q460钢柱抗火性能的影响,采用ANSYS有限元程序建立了考虑蠕变的钢柱抗火分析模型,利用普通钢柱试验数据对其进行了验证。引入高强度Q460钢材在高温下的力学参数和高温蠕变参数,利用有限元方法进行了考虑蠕变效应的高强度Q460钢柱在多个参数下的抗火分析,与普通钢柱和现行CECS 200∶2006《建筑钢结构防火技术规范》的计算结果进行了对比。结果表明:长细比、荷载比、升温速率对考虑蠕变效应后高强度Q460钢柱的抗火性能有明显的影响。高强度Q460钢柱的抗火性能优于普通钢柱,CECS 200∶2006中钢柱的抗火设计结果不适用于高强度Q460钢柱。
Under the action of high temperature and load,the creep deformations develop in steel and significantly affect the deformation and bearing capacity of steel structures in fire. In order to study the effect of high temperature creep on fire resistance of high strength Q460 steel columns,finite element model for analyzing fire resistance of steel column was established by ANSYS. The finite element result was verified by fire test data of normal steel columns and good agreement was found after considering the creep effect. The validated model was used to carry out a set of parametric studies by introducing the mechanical properties and creep parameters of high strength steel at high temperature. The critical temperature and stability factor of high strengh Q460 steel columns were compared with the results of normal steel columns and fire resistance design code. The study showed that the value of the slenderness ratio,loading ratio and heating rate had a significant influence on the fire resistance of high strength Q460 steel columns after considering high temperature creep. The fire resistance of high strength Q460 steel columns was better than normal steel columns,and the results given in Code for Fire Safety of Steel Structures in Buildings（ CECS200∶ 2006） were not applicable to high strength Q460 steel columns.
出处
《工业建筑》
CSCD
北大核心
2016年第7期74-80,共7页
Industrial Construction
基金
重庆市自然科学基金项目(cstc2013jcyj A30010)
关键词
蠕变
高强度钢
钢柱
抗火
creep
high strength steel
steel column
fire resistance
