[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()

FRP加固RC圆柱正截面受弯承载力计算

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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

FRP加固RC圆柱正截面受弯承载力计算

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

顾冬生¹;  2;  吴刚²;  吴智深²

¹江南大学环境与土木工程学院, 无锡 214122; ²东南大学混凝土及预应力混凝土结构教育部重点实验室, 南京 210096

Keywords:

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

钢筋混凝土圆柱;  正截面受弯承载力;  纤维增强复合材料;  约束

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.

运用数值计算方法对FRP加固钢筋混凝土(RC)圆柱截面特性进行计算, 发现截面破坏时受压区高度主要受轴压比、FRP约束强度比和纵筋配筋特征值3个主要参数影响. 根据数值计算的结果进行回归, 提出了受压区对应圆心角θ的计算方法. 数值计算结果显示, 横向约束导致的混凝土应力提高以及纵筋屈服后的强化效应使RC柱破坏时截面受弯承载力远大于规范规定值. 根据理论分析和36个大比例试件实测结果提出截面破坏时受弯承载力计算方法, 计算结果与试验结果吻合很好. 最后, 对一个典型柱变形能力进行参数分析, 研究轴压比, 纵筋配筋特征值和FRP约束强度比对正截面变弯承载力的影响.结果显示FRP加固圆柱破坏时受弯承载力可以比规范规定的未加固柱受弯承载力提高50%左右.

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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