Finite Element Modeling of Insulated FRP-Strengthened RC Beams Exposed to Fire
Finite Element Modeling of Insulated FRP-Strengthened RC Beams Exposed to Fire
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DOI：
10.1061/(asce)cc.1943-5614.0000509
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发表时间：
2015-04-01
影响因子：
4.6
通讯作者：
Teng, J. G.
中科院分区：
文献类型：
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作者：
Dai, Jian-Guo;Gao, Wan-Yang;Teng, J. G.
外贴纤维增强聚合物(FRP)层压板加固钢筋混凝土(RC)构件的耐火性能一直是人们关注的问题，特别是在建筑应用中。为了达到建筑设计规范规定的结构耐火等级，通常需要提供保温层。本文首次提出了用三维有限元方法模拟FRP加固钢筋混凝土梁的耐火性能。该方法仔细考虑了混凝土、钢和FRP的本构模型，以及FRP-混凝土和钢-混凝土界面的粘结滑移行为。将有限元预测结果与现有试验数据进行了比较，验证了所提出的有限元方法的准确性。数值计算结果表明，以往数值计算方法所采用的FRP与混凝土之间完美粘结的假设导致了对挠度的低估，从而导致了不安全的抗火预测。本文提出的有限元方法可直接应用于基于性能化的消防安全设计或旨在制定简化设计规则的参数研究中。(C)2014年美国土木工程师学会。
The fire performance of reinforced concrete (RC) members strengthened with externally bonded fiber-reinforced polymer (FRP) laminates has been an issue of significant concern, particularly for building applications. To achieve structural fire-resistance ratings as specified in building design codes, an insulation layer often needs to be provided. This paper presents the first three-dimensional finite element (FE) approach for the fire performance simulation of insulated FRP-strengthened RC beams. The proposed approach gives careful considerations to the constitutive modeling of concrete, steel, and FRP, as well as the bond-slip behavior of FRP-to-concrete and steel-to-concrete interfaces. Comparisons between FE predictions and existing test data are presented to demonstrate the accuracy of the proposed FE approach. Numerical results obtained with the present FE approach show that the assumption of perfect bonding between FRP and concrete as adopted in previous numerical approaches leads to underestimations of deflections and thus unsafe predictions of fire resistance. The FE approach presented in the paper can be directly applied in performance-based fire safety design, or in parametric studies aimed at developing simplified design rules. (C) 2014 American Society of Civil Engineers.