梁端约束对钢筋混凝土梁耐火性能的影响  

Effect of Restraint Stiffness on the Fire Resistance of Reinforced Concrete Beam

作　　者：卢锦钟[1] 黄晓吉[2] 

机构地区：[1]华南理工大学亚热带建筑科学国家重点实验室,广东广州510640 [2]华东交通大学土木建筑学院,江西南昌330013

出　　处：《华侨大学学报（自然科学版）》2008年第4期593-599,共7页Journal of Huaqiao University(Natural Science)

基　　金：国家自然科学基金资助项目(50478078);教育部新世纪优秀人才支持计划(NCET-04-0819)

摘　　要：利用已编制的钢筋混凝土结构高温反应的全过程分析程序,通过带有杆端约束的钢筋混凝土梁的耐火极限分析,初步探讨轴向约束刚度比、转动约束刚度比和高跨比对梁的耐火性能的影响规律.研究表明,转动约束刚度比不变时,随着轴向约束刚度比的增大,梁的耐火极限逐渐减少,当轴向约束刚度比增大到一定程度时,这一趋势逐渐减缓;轴向约束刚度比不变时,随着转动约束刚度比的增大,梁的耐火极限逐渐增大,当转动约束刚度比增大到一定程度时,这一趋势逐渐减缓;随着高跨比的减少,梁的耐火时间逐渐减少.A computer program considering geometrical nonlinearity for reinforced concrete structure subjected to high temperature is used, the reliability of the program is validated by the existed experimental results. A reinforced concrete beam with restraint stiffness is selected for the fire endurance analysis, the effect of the axial and rotational restraint stiffness ratios, and the height-span ratio on the fire resistance of the reinforced concrete beam is primarily studied. Simulation results show that for a constant ratio of rotational restrained stiffness, with increasing the ratio of axial restraint stiffness, the fire resistance of beam decreases, and this trend slows down as the axial restraint stiffness increases to a certain value; for a constant ratio of axial restraint stiffness, with increasing the ratio of rotational restraint stiffness, the fire resistance of beam increases, and this trend also slows down as the rotational restraint stiffness increases to a certain value; with decreasing the height-span ratio, the fire resistance of beam decreases.

关 键 词：钢筋混凝土梁 轴向约束 转动约束 耐火极限 

分 类 号：TU352.503[建筑科学—结构工程] TU375.1