摘要
基于ABAQUS软件平台,开发了适用于钢筋混凝土框架结构火灾反应分析的梁单元用户材料模型及子程序,从而可以较为准确地模拟火灾下钢筋混凝土构件的截面温度场.基于塑性增量理论,对在恒定加载与标准升温耦合作用下的钢筋混凝土框架结构模型进行了非线性全过程分析.通过不同受火工况下的非线性全过程分析,揭示了钢筋混凝土框架结构在火灾高温和荷载共同作用下塑性铰的分布规律和结构损伤机制,分析了发生火灾的房间位置对框架结构破坏机制的影响,进而对发生火灾的最不利位置进行了探讨.分析结果表明,钢筋混凝土框架结构构件内力随受火温度升高不断重新分布,构件受热膨胀引起的约束内力与荷载内力叠加将导致其出现塑性铰;受火房间的位置对钢筋混凝土框架结构塑性铰的分布和破坏机制有明显影响,因此,结构抗火设计时应考虑受火房间的不利位置.
Based on software ABAQUS, a user material model and subroutine for the analysis of reinforced concrete frame structures in a fire were developed to simulate the cross-section temperature field of reinforced concrete components more accurately. With the incremental theory of plasticity, the non-linear analysis of a reinforced concrete frame model subjected to a dead load and a local fire at different conditions were carried out. Based on the non-linear analysis results, the distribution of plastic hinges and the damage mechanism of the reinforced concrete frame in a fire were revealed, and the effects of fire room location on the failure mechanism of reinforced concrete frames were discussed. In the end, the most dangerous location of fire room was explored. The analysis results indicate that the reinforced concrete frame members undergo internal force redistribution under a fire, and the superposition of constraint internal forces with external loads causes plastic hinges in beams and columns. In addition, the distribution of plastic hinges and the damage mechanism of reinforced concrete frames are affected obviously by fire room location, so the disadvantage of fire room location should be considered in a fire resistant design.
出处
《西南交通大学学报》
EI
CSCD
北大核心
2009年第5期697-703,709,共8页
Journal of Southwest Jiaotong University
基金
国家自然科学基金资助项目(50678097)
山东省自然科学基金资助项目(Y2006F30)
