Title: Reinforced geopolymer cement concrete in flexure: A closer look at stress-strain performance and equivalent stress-block parameters
Date Published: November-December 2016
Volume: 61
Issue: 6
Page Numbers: 30-43
Authors: Brett Tempest, Janos Gergely, and Ashley Skipper
https://doi.org/10.15554/pcij61.6-02

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Abstract

Geopolymer cement concrete could revolutionize the concrete industry by merging the benefits of concrete with significantly reduced greenhouse gas emissions compared with portland cement concrete. Several authors have verified the applicability of equivalent stress-block design parameters to estimating the capacity of reinforced geopolymer cement concrete beams. These verifications have been made primarily by testing smalldimension, underreinforced beams with fairly shallow compression zones. The research presented in this paper used a combined axial stress and flexure test developed by Hognestad et al. as a primary means of determining the distribution of stresses in the compression zone of geopolymer cement concrete in flexure. The results indicated that slightly modified stress block parameters α1 and β1 should be applied to geopolymer cement concrete due to differences in the stress-strain relationship of geopolymer cement concrete in compression compared with portland cement concrete. Although these parameters do not significantly improve the accuracy of calculations for small-dimension beams, they are more appropriate for general design conditions, which might include deeper beams, heavily reinforced sections, and prestressed sections.

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