1.山东建筑大学土木工程学院,山东 济南 250101
2.山东建筑大学建筑结构加固改造与地下空间工程教育部重点实验室;山东 济南 250101
3.东南大学混凝土与预应力混凝土教育部重点实验室,江苏 南京 210096
4.东南大学土木工程学院,江苏 南京 210096
王玉镯(1973—),男,教授,硕导,博士。主要从事工程结构抗火研究。E-mail: yuzhuowang@163.com
收稿:2022-08-29,
修回:2022-12-03,
纸质出版:2024-02-15
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王玉镯,邱昊,徐天贵等.火灾中钢筋混凝土两端固结梁破坏模式变化规律[J].防灾减灾工程学报,2024,44(01):192-201.
WANG Yuzhuo,QIU Hao,XU Tiangui,et al.Change Law of Failure Modes of Reinforced Concrete Beams with Fixed Ends in Fire[J].Journal of Disaster Prevention and Mitigation Engineering,2024,44(01):192-201.
王玉镯,邱昊,徐天贵等.火灾中钢筋混凝土两端固结梁破坏模式变化规律[J].防灾减灾工程学报,2024,44(01):192-201. DOI: 10.13409/j.cnki.jdpme.20220829003.
WANG Yuzhuo,QIU Hao,XU Tiangui,et al.Change Law of Failure Modes of Reinforced Concrete Beams with Fixed Ends in Fire[J].Journal of Disaster Prevention and Mitigation Engineering,2024,44(01):192-201. DOI: 10.13409/j.cnki.jdpme.20220829003.
为了研究火灾过程中钢筋混凝土两端固结梁破坏模式的变化规律,利用有限元分析软件对梁内部的温度场进行分析,确定其不同耐火时刻的分布规律,利用承载力简化计算公式对火灾过程中钢筋混凝土梁不同时刻的极限承载力进行计算分析。并对上侧纵筋配筋面积、混凝土保护层厚度和混凝土强度为变换因素的三组固结梁试件进行理论分析,讨论了火灾过程中不同参数对钢筋混凝土固结梁破坏模式临界点ξ变化规律的影响。结果表明:上侧纵筋配筋面积越大,ξ点对应受火时间T越提前;混凝土保护层厚度越大,混凝土强度越高,ξ点对应受火时间T越滞后。在理论计算的基础上,为保证梁在受火两小时内发生弯曲破坏,对梁的防火设计提供了思路。本研究方法可以简化分析钢筋混凝土梁高温中破坏模式的变化规律,为火灾中构件的设计计算提供参考。
In order to study the changes in the failure modes of reinforced concrete beams with fixed ends in fire, the temperature field inside a beam was analyzed using finite element analysis software and its distribution at different fire resistance times was determined. The ultimate bearing capacity of the reinforced concrete beam at different fire times was calculated using the simplified calculation formula of bearing capacity. Theoretical analysis was conducted on three sets of beam specimens with fixed ends, taking the upper longitudinal reinforcement area, concrete cover thickness, and concrete strength as transformation factors. The influence of different parameters on the changes of critical point
ξ
in the failure mode of the reinforced concrete beams during fire was discussed. The results show that the larger the reinforcement area of the upper longitudinal reinforcement, the earlier the fire time T of the point
ξ
. The thicker the concrete protective layer and the higher the strength of the concrete, the later the fire time T corresponds to the point
ξ.
To ensure that the beams undergo bending failure within two hours of being exposed to fire, ideas for the fire protection design of beams are provided based on theoretical calculations. The presented method can simplify the analysis of the changes in failure modes of reinforced concrete beams at high temperatures, and provide a reference for the design and calculation of components in fires.
时旭东 , 过镇海 . 不同混凝土保护层厚度钢筋混凝土梁的耐火性能 [J]. 工业建筑 , 1996 ( 9 ): 11 - 13,18 .
Shi X D , Guo Z H . Experimental studies on fire resistance of reinforced concrete beams with different thickness concrete covers [J]. Industrial Construction , 1996 ( 9 ): 11 - 13,18 . (in Chinese)
Reddy D V , Sobhan K , Liu L X , et al . Size effect on fire resistance of structural concrete [J]. Engineering Structures , 2015 , 99 : 468 - 478 .
Ellingwood B , Lin T D . Flexure and shear behavior of concrete beams during fire [J]. ASCE , Journal of Structural Engineering, 1991 , 117 ( 2 ): 440 - 457 .
杨志年 , 齐建全 , 段开达 , 等 . 钢筋混凝土梁高温下抗剪性能的试验研究 [J]. 工业建筑 , 2020 , 50 ( 10 ): 57 - 62 .
Yang Z N , Qi J Q , Duan K D , et al . Experiment study on shear properties of rc beams under high temperature [J]. Industrial Construction , 2020 , 50 ( 10 ): 57 - 62 . (in Chinese)
Khan M S , Prasad J , Abbas H . Shear strength of RC beams subjected to cyclic thermal loading [J]. Construction and Building Materials , 2010 , 24 ( 10 ): 1869 - 1877 .
陆洲导 , 朱伯龙 , 周跃华 . 钢筋混凝土简支梁对火灾反应的试验研究 [J]. 土木工程学报 , 1993 ( 3 ): 47 - 54 .
Lu Z D , Zhu B L , Zhou Y H . Experimental studies on fire response of reinforced concrete simply supported beams [J]. China Civil Engineering Journal , 1993 ( 3 ): 47 - 54 . (in Chinese)
丁发兴 , 姚飞 , 李喆 , 等 . 高温下钢筋混凝土简支梁的抗火性能 [J]. 东北大学学报(自然科学版) , 2015 , 36 ( 10 ): 1476 - 1481 .
Ding F X , Yao F , Li Z , et al . Fire resistance of simple supported reinforced concrete beams under high temperature [J]. Journal of Northeastern University(Natural Science) , 2015 , 36 ( 10 ): 1476 - 1481 . (in Chinese)
张威振 . 高温下足尺钢筋混凝土梁试验研究及数值分析 [J]. 哈尔滨工业大学学报 , 2009 , 41 ( 2 ): 198 - 201 .
Zhang W Z . Experimental investigation and numerical analysis for RC beams under elevated temperature [J]. Journal of Harbin Institute of Technology , 2009 , 41 ( 2 ): 198 - 201 . (in Chinese)
廖艳芬 , 漆雅庆 , 马晓茜 . 火灾下钢筋混凝土梁非线性有限元分析 [J]. 工业建筑 , 2011 , 41 ( 7 ): 31 - 37 .
Liao Y F , Qi Y Q , Ma X Q . Nonlinear finite element analysis of reinforced concrete beams iln fire [J]. Industrial Construction , 2011 , 41 ( 7 ): 31 - 37 . (in Chinese)
Lin X S , Zhang Y X , Nonlinear finite element analyses of steel/FRP-reinforced concrete beams in fire conditions [J]. Composite Structures , 2013 , 97 : 277 - 285 .
梁兴文 , 李晓文 . 基于混凝土强度准则的梁斜截面受剪承载力分析 [J]. 工业建筑 , 1996 ( 3 ): 8 - 11 .
Liang X W , Li X W . Analysis of shear capaciy for reinforced concrete beam based on concrete strength criterion [J]. Industrial Construction , 1996 ( 3 ): 8 - 11 . (in Chinese)
杨建平 , 时旭东 , 过镇海 . 高温下钢筋混凝土梁极限承 载力的简化计算 [J]. 工业建筑 , 2002 , 32 ( 3 ): 26 - 28 .
Yang J P , Shi X D , Guo Z H . Simplified calculation of ultimate load bearing capacity of reinforced concrete beams under high temperature [J]. Industrial Construction , 2002 , 32 ( 3 ): 26 - 28 . (in Chinese)
Wang Y Z , Fu C G . Calculation of ultimate bearing capacity of prestressed steel reinforced concrete structure under fire [J]. Advanced Materials Research , 2011 , 250-253 : 2857 ‑ 2860 .
刘殿魁 , 林敏 . 火灾作用下钢筋混凝土构件等效火灾荷载的计算 [J]. 哈尔滨工程大学学报 , 2007 ( 5 ): 519 - 524 .
Liu D K , Lin M . Calculation of equivalent fire load for RC members subjected to fire [J]. Journal of Harbin Engineering University , 2007 ( 5 ): 519 - 524 . (in Chinese)
尹安康 . 火灾作用下有腹筋钢筋混凝土简支梁抗剪性 能试验研究 [D]. 济南 : 山东建筑大学 , 2018 .
Yin A K . Experimental study on shear bearing capacity of reinforced concrete simple supported beams with web bar under fire [D]. Ji'nan : Shandong Jianzhu University , 2018 . (in Chinese)
EN 1994-1-2, The European Standard [S]. Eurocode 4:Design of Composite and Concrete Structure,Partl. 2: Structural Fire Design, 2011 .
Lie T T . Fire resistance of circular steel columns filled with bar-reinforced concrete [J]. Journal of Structural Engineering , 1994 , 120 ( 5 ): 1489 - 1509 .
周淼 . 火灾高温作用下钢筋混凝土梁抗剪承载力研究 [D]. 济南 : 山东建筑大学 , 2015 .
Zhou M . Research on the shear capacity of reinforced concrete beams in fire [D]. Ji'nan : Shandong Jianzhu University , 2015 . (in Chinese)
吕彤光 . 钢筋高温性能的实验研究 [D]. 北京 : 清华大学 , 1996 .
Lyu T G . Experimental study on high temperature performance of rebar [D]. Beijing : Tsinghua University , 1996 . (in Chinese)
混凝土结构设计规范 : GB 50010—2010 [S]. 北京 : 中国建筑工业出版社 , 2015 .
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