摘要
为研究混凝土板在双向面内约束作用下的火灾行为,对4块混凝土矩形板进行恒载-升温条件下的火灾试验,获得试验板沿板厚的温度场分布、钢筋温度、板平面内外变形、板角约束力和破坏模式等规律。在此基础上,编程对试验板的温度场、变形行为和薄膜机理进行数值分析。结果表明:对于双向面内约束板,其裂缝模式与简支板和单向约束板不同;面内约束作用致使混凝土板后期变形及变形速率增大;不同面内约束下混凝土板具有不同的薄膜机理;相比单向面内约束,双向约束作用更不利于混凝土板受拉薄膜效应发展。
To analyze the fire behavior of two-way concrete slabs with bi-axial in-plane restraints, four fire tests were conducted on the full-scale rectangular concrete slabs subjected to constant loads. The test results included the temperature field along the depth of the slab, the reinforcement temperature, the out-plane and in-plane deflections, the constraint force and the failure mode of comers. In addition, a program was developed to analyze the temperature, deflection and membrane action of the tested concrete slabs. The results indicate that the cracking pattern of the slab： with bi-axial in-plane restraints is clearly different from those of the simply-supported slabs and the uniaxial restrain slabs. The in-plane restraint will induce the larger deflection and deflection ratios of the concrete slabs at the later stage of fire. The concrete slabs with different restraints have different membrane mechanism. Compared to the uniaxial in- plane restraints, the bi-axial restraint is more prone to constrain development of tensile membrane action in concrete slabs.
作者
王勇
袁广林
王腾焱
王跃翔
史伟男
Wang Yong;Yuan Guanglin;Wang Tengyan;Wang Yuexiang;Shi Weinaa(State Key Laboratory for Geomechanics and Deep Underground Engineering, China University of Mining ＆ Technology, Xuzhou 221008, China;JiangSu Collaborative Innovation Center for Building Energy Saving and Construct Technology, Xuzhou 221008, China;Key Laboratory of Concrete and Prestressed Concrete Structures of Ministry of Education, Southeast University, Nanjing 210096, China)
出处
《土木工程学报》
EI
CSCD
北大核心
2018年第5期48-59,共12页
China Civil Engineering Journal
基金
国家青年科学基金(51408594)
中国博士后科学基金特别资助项目(2016T90525)
中国博士后科学基金(2014M560461)
中央高校基本科研业务费专项资金(2014QNA78)
江苏建筑节能与建造技术协同创新中心资助项目(SJXTQ1614)
关键词
钢筋混凝土双向板
火灾试验
数值分析
面内约束
温度
变形
two-way reinforced concrete slab
fire test
numerical analysis
in-plane restraint
temperature
deflection
