摘要
采用试验验证的有限元模型对火灾下未发生和发生混凝土爆裂的钢管混凝土叠合柱的耐火性能进行分析,包括温度场、轴向变形-时间曲线、截面内力和破坏模式等。研究结果表明:火灾下发生混凝土爆裂的叠合柱,截面内混凝土的温度更高,爆裂深度越大,截面内温度越高;混凝土的爆裂面积比、爆裂深度和爆裂位置均对叠合柱耐火性能有影响;混凝土爆裂后,钢管内的核心混凝土和钢管承担的荷载明显增大,钢管外的钢筋混凝土结构承载的荷载明显下降;达到耐火极限时,发生混凝土爆裂的叠合柱的破坏模式可能发生变化。
The fire resistance of concrete-encased concrete filled steel tubular （CFST） column was studied. Experimental verified fi- nite element models were established. The models included specimens with and without concrete spalling. Temperature distribu- tion, vertical deformation versus time curve, internal forces of cross section and failure modes were studied. The results showed that： the cross section temperatures of concrete-encased CFST col- umns with concrete spalling were higher. The deeper the concrete spalling, the higher the temperatures of cross section. Concrete spalling area ratio, depth and position can influence the fire resis- tance of concrete-encased CFST columns. The internal forces of core concrete and steel tube after concrete spalling were significantly increased, and the internal forces of reinforced concrete structure were obviously decreased. The failure mode of concrete-en- cased CFST column with concrete spalling may be different under fire resistance limit circumstances.
出处
《消防科学与技术》
CAS
北大核心
2017年第9期1182-1186,共5页
Fire Science and Technology
基金
国家自然科学基金项目(51408134)
关键词
钢管混凝土叠合柱
耐火性能
爆裂
有限元法
concrete-encased concrete filled steel tubular column
fire resistance
spalling
finite element method
