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Indexed by:期刊论文

Date of Publication:2021-01-13

Journal:ENGINEERING STRUCTURES

Volume:31

Issue:10

Page Number:2495-2505

ISSN No.:0141-0296

Key Words:CFRP; Concrete column; Partial deteriorated strength; Partial confinement

Abstract:Fiber reinforced polymer (FRP) composites are becoming more frequently used in civil engineering structures because of their superior advantages. The majority of applications undertaken in the past focused on entire wrapping with FRP, while in practice, affected by frost damage, aging or construction quality, some part of the concrete columns might have deteriorated, that is the strength of the deteriorated part might be lower than the other parts. in these cases, conventional retrofitting was wrapping the whole column including the intact and the deteriorated parts. That has been considered as a kind of waste. Few literatures have been involved in a partial confinement method for parts with locally deteriorated strength. This paper is to present an effective partial confinement method, to investigate the mechanical behavior of columns with partial deteriorated strength and to evaluate the availability of the partial confinement. Five groups of plain columns and five steel reinforced concrete columns have been tested, each specimen has two different strengths, among these the lower one is to simulate the part with deteriorated strength. Different layers of CFRP sheets have been wrapped just on the lower strength part to explore the improvement by partial confinement. Experimental results indicate that both the strength and the ductility of the deteriorated strength part could be significantly increased, subsequently; the load capacity of the entire column can be enhanced higher than those of the original columns. An existing analytical model on FRP reinforcement is used to predict the ultimate load and to evaluate the improvement effectiveness of partial confinement. The prediction provided by theoretical model shows well agreements with the experimental results. Findings of this paper presents that partial confinement on deteriorated parts of concrete columns would be developed as an alternative approach to avoid cost and time-consumption in practice. (C) 2009 Elsevier Ltd. All rights reserved.