[1] Gu Dongsheng, Wu Gang, Wu Zhishen, et al. Ultimate flexural strength of normal sectionof FRP-confined RC circular columns [J]. Journal of Southeast University (English Edition), 2010, 26 (1): 107-111. [doi:10.3969/j.issn.1003-7985.2010.01022]

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Ultimate flexural strength of normal sectionof FRP-confined RC circular columns()

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Journal of Southeast University (English Edition)[ISSN:1003-7985/CN:32-1325/N]

Volumn:

26

Issue:

2010 1

Page:

107-111

Research Field:

Civil Engineering

Publishing date:

2010-03-30

Info

Title:

Ultimate flexural strength of normal sectionof FRP-confined RC circular columns

Author(s):

Gu Dongsheng¹;  2;  Wu Gang²;  Wu Zhishen²

¹College of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China
²Key Laboratory of Concrete and Pre-Stressed Concrete Structures of the Ministry of Education, Southeast University, Nanjing 210096, China

Keywords:

reinforced concrete(RC)circular columns;  flexural capacity of normal section;  fiber-reinforced polymer(FRP);  confinement

PACS:

TU375.3

DOI:

10.3969/j.issn.1003-7985.2010.01022

Abstract:

Numerical analysis is carried out to study the sectional properties of the fiber-reinforced polymer(FRP)-confined reinforced concrete(RC)circular columns. The axial load ratio, the FRP confinement ratio and the longitudinal reinforcement characteristic value are the three main parameters that can influence the neutral axis depth when concrete compression strain reaches an ultimate value. The formula for computing the central angle θ, corresponding to the compression zone, is established according to the data regression of the numerical analysis results. The numerical analysis results demonstrate that the concrete stress enhancement from transverse confinement and strain hardening of the longitudinal reinforcement can cause a much greater flexural strength than that defined by the design code. Based on the analytical studies and the test results of 36 large scale columns, the formula to calculate the flexural strength when columns fail under seismic loading is proposed, and the calculated results agree well with the test results. Finally, parametric studies are conducted on a typical column with different axial load ratios, longitudinal reinforcement characteristic value and FRP confinement ratios. Analysis of the results shows that the calculated flexural strength can be increased by 50% compared to that of unconfined columns defined by the code.

References:

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Memo

Memo:

Biographies: Gu Dongsheng(1978—), male, doctor, lecturer, gussds@yahoo.com.cn; Wu Gang(1976—), male, doctor, professor, g.wu@seu.edu.cn.
Foundation items: The National Basic Research Program of China(973 Program)(No.2007CB714200), the National Natural Science Foundation of China(No.50608015, 50908102).
Citation: Gu Dongsheng, Wu Gang, Wu Zhishen. Ultimate flexural strength of normal section of FRP-confined RC circular columns[J]. Journal of Southeast University(English Edition), 2010, 26(1): 107-111.

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