Strain gradient effects on concrete stress–strain curve

Peng, Jun and Ho, Johnny Ching Ming (2012) Strain gradient effects on concrete stress–strain curve. Proceedings of the Institution of Civil Engineers: Structures and Buildings, 165 SB10: 543-565. doi:10.1680/stbu.10.00056

Attached Files (Some files may be inaccessible until you login with your UQ eSpace credentials)
Name Description MIMEType Size Downloads
UQ352203_OA.pdf Full text (open access) application/pdf 892.38KB 0

Author Peng, Jun
Ho, Johnny Ching Ming
Title Strain gradient effects on concrete stress–strain curve
Journal name Proceedings of the Institution of Civil Engineers: Structures and Buildings   Check publisher's open access policy
ISSN 0965-0911
Publication date 2012
Year available 2012
Sub-type Article (original research)
DOI 10.1680/stbu.10.00056
Open Access Status File (Publisher version)
Volume 165
Issue SB10
Start page 543
End page 565
Total pages 23
Place of publication London, United Kingdom
Publisher I C E Publishing
Collection year 2012
Language eng
Formatted abstract
The stress–strain characteristic of concrete developed in flexure is one of the essential parameters for the ultimate
flexural strength design of reinforced concrete (RC) members. Currently, the stress–strain curve of concrete
developed in flexure is obtained by scaling down the uniaxial stress–strain curve. In current RC design codes, it is
represented by an equivalent rectangular concrete stress block depending solely on the concrete strength. By
comparing the theoretical strength evaluated for the stress block with the measured strength, the authors found
that current codes underestimate the actual flexural strength of RC beams and columns by 9% and 19%, respectively.
Since the underestimation is different for beams and columns, which are subjected to different strain gradients at ultimate, it is suggested that the maximum concrete stresses developed in flexure should depend also on strain gradient. The effects of strain gradient on the concrete stress developed in flexure were investigated in this work by testing RC columns under concentric and eccentric axial loads or horizontal loads. The concrete stress–strain curves of the eccentrically/horizontally loaded specimens were derived by modifying those of concentrically loaded counterparts based on axial force and moment equilibriums. The results indicate that the maximum concrete stress developed in flexure depends significantly on strain gradient. Formulas were developed to correlate the maximum and equivalent concrete stresses developed in flexure to the strain gradient. Their applicability was verified by comparing the results with measured flexural strengths of RC beams and columns.
Keyword Drainage and irrigation
Floods and floodworks
Mathematical modelling
Q-Index Code C1
Q-Index Status Provisional Code
Institutional Status Non-UQ

Document type: Journal Article
Sub-type: Article (original research)
Collection: School of Civil Engineering Publications
Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 1 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 0 times in Scopus Article
Google Scholar Search Google Scholar
Created: Thu, 23 Oct 2014, 17:31:45 EST by Johnny Ho on behalf of School of Civil Engineering