Simple Method for Predicting Temperatures in Insulated, FRP-Strengthened RC Members Exposed to a Standard Fire
Publication: Journal of Composites for Construction
Volume 19, Issue 6
Abstract
Fire safety is a significant concern for fiber-reinforced-polymer (FRP)–strengthened RC structures, particularly for indoor applications. To satisfy fire resistance requirements, fire insulation layers may be provided to protect FRP-strengthened RC members. This paper presents a simple, design-oriented method for predicting temperatures in insulated FRP-strengthened RC members under standard fire exposure. The proposed method consists of two sets of formulas: one set for predicting temperatures in unprotected FRP-strengthened RC members exposed to a standard fire; and another set to convert a fire insulation layer into an equivalent concrete layer. As a result, an insulated FRP-strengthened RC member can be analyzed as an unprotected RC member with an enlarged section for which a similar simple method has previously been established by these authors. In the present study, a finite element (FE) approach for the temperature analysis of insulated FRP-strengthened RC members was first developed and then verified using existing test data. Then the verified FE approach was employed in a parametric study to generate extensive numerical data, on which the second set of formulas were established. The proposed temperature prediction method is shown to provide accurate predictions of both FE results and test data of insulated FRP-strengthened RC members.
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Acknowledgments
The authors are grateful for the financial support received from the National Basic Research Program of China (i.e., the 973 Program) (Project No. 2012CB026201) and the National Natural Science Foundation of China (NSFC) (Project Nos. 51408521 and 51478406). They are also grateful for a postdoctoral fellowship awarded to the first author by the Faculty of Construction and Environment of the Hong Kong Polytechnic University.
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Journal of Composites for Construction
Volume 19 • Issue 6 • December 2015
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© 2015 American Society of Civil Engineers.
History
Received: Aug 3, 2014
Accepted: Jan 6, 2015
Published online: Mar 17, 2015
Discussion open until: Aug 17, 2015
Published in print: Dec 1, 2015
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