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Updated: Oct 12, 2025
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Preparation of Aligned Steel Fiber Reinforced Cementitious Composite and Its Flexural Behavior
Published on: June 27, 2018
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Fiber Reinforced Compressed Earth Blocks: Evaluating Flexural Strength Characteristics Using Short Flexural Beams
Peter Donkor1, Esther Obonyo2, Christopher Ferraro3
1M.E. Rinker School of Construction Management, University of Florida, Gainesville, FL 32611, USA.
Materials (Basel, Switzerland)
|November 27, 2021
Summary
Adding polypropylene (PP) fibers to compressed earth blocks (CEB) significantly improves their flexural performance and ductility. This enhancement is crucial for structural applications, especially in high-wind regions, making CEB more viable.
Area of Science:
- Materials Science
- Civil Engineering
- Sustainable Construction
Background:
- Compressed earth blocks (CEB) have limitations in tensile and flexural strength, hindering their use in structural applications, particularly against lateral loads like high winds.
- Cementitious matrices in CEB are inherently brittle, requiring reinforcement to improve mechanical properties for broader structural deployment.
Purpose of the Study:
- To investigate the effectiveness of polypropylene (PP) fibers in enhancing the flexural performance of compressed earth blocks (CEB).
- To quantify the impact of varying PP fiber content on key material properties related to flexural strength and toughness.
Main Methods:
- Preparation of plain and PP fiber-reinforced CEB specimens with varying fiber mass content (0.2% to 1.0%) and a constant ordinary Portland cement (OPC) content of 8%.
- Flexural performance testing of specimens using the Standard Test Method for Flexural Performance of Fiber-Reinforced Concrete (ASTM C1609).
- Quantification of material properties including first-peak strength, peak strength, equivalent flexural strength, residual strength, and flexural toughness.
Main Results:
- Inclusion of PP fibers demonstrated a notable improvement in the flexural performance of CEB specimens.
- Specimens with PP fiber content exceeding 0.6% exhibited deflection-hardening behavior, indicating enhanced ductility.
- Quantified improvements in flexural toughness and residual strength were observed with fiber reinforcement.
Conclusions:
- Polypropylene fibers are effective in enhancing the flexural strength and ductility of compressed earth blocks.
- Optimal fiber content for improved performance, including deflection-hardening, was identified.
- The findings support the increased viability of CEB for structural applications, particularly in wind-prone areas, and propose a predictive model for equivalent flexural strength.
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