Redon et al. 2001 - Measuring and modifying interface properties of PVA fibers in ECC matrix

Citation

Redon, C., Li, V.C., Wu, C., Hoshiro, H., Saito, T., Ogawa, A. (2001). Measuring and modifying interface properties of PVA fibers in ECC matrix. Journal of Materials in Civil Engineering (ASCE), 13(6), 399-406.

• DOI: 10.1061/(ASCE)0899-1561(2001)13:6(399) (verified via Crossref API, batch 2)

Source paths

• PDF: 00_sources/foundational_papers/originals/redon-2001-measuring-and-modifying-interface-properties-of.pdf
• Extracted full text: 00_sources/foundational_papers/extracted_text/redon-2001-measuring-and-modifying-interface-properties-of.md
• Source note: 00_sources/foundational_papers/source_notes/redon-2001-measuring-and-modifying-interface-properties-of.md

Why the paper matters for the Atlas

• First systematic single-fiber pullout characterization of PVA fibers in an ECC matrix, quantifying the three interface parameters that feed the sigma(delta) law: chemical debonding energy G_d, initial frictional bond t0, and slip-hardening coefficient beta.
• Identifies the failure mode that limits PVA-ECC ductility: fiber rupture by delamination caused by strong slip hardening from surface abrasion, not by chemical debonding.
• Proposes the oil-coating surface treatment used in every subsequent PVA-ECC design paper (Li, Wang, Wu 2001; Li et al. 2002; Yang et al. 2008) to lower G_d and cap slip hardening.
• Direct upstream reference for the Atlas nodes fiber_bridging_law, micromechanics_based_design, and any future interface_properties concept node.

Direct evidence extracted from source note / full text

• Two fiber types tested: Fiber A (0.044 mm diameter, 0.8 mm embedment) and Fiber B (0.700 mm diameter, 5 mm embedment) in the same ECC mortar (source note Section 3).
• Pullout speed 0.02 mm/s on MTS 810 (source note Section 3).
• G_d and t0 can be extracted from a partial-pullout curve even when fiber ruptures before full pullout, using the simplified Lin et al. (1999) model (source note Sections 2, 4).
• PVA fibers exhibit strong slip hardening (high beta), causing severe surface abrasion and fiber rupture by delamination; rupture occurs when apparent fiber tensile strength is exceeded during slip, not during chemical debonding (source note Sections 2, 4).
• Applying an oil coating on the hydrophilic PVA fiber surface partially reduces both G_d and t0 and reduces fiber rupture during pullout (source note Section 4).

Key equations and parameters

• Interface parameter set (G_d, t0, beta) extracted from single-fiber pullout Pa -> Pb load drop and post-drop slope, per the simplified Lin et al. (1999) model. Exact equations, coefficient values, and figure numbers: needs verification against the original PDF.
• Quantitative values of G_d, t0, beta for oil-coated vs uncoated PVA in this paper are not stated in the source note; needs verification against the original PDF.

Atlas node links

• Concept nodes: 02_concepts/fiber_bridging_law.md, 02_concepts/micromechanics_based_design.md, 02_concepts/strain_hardening_criteria.md.
• Experiment nodes: 05_experiments/direct_tensile_test.md (indirect: interface parameters feed the composite bridging law measured in direct tension).
• Related paper cards: lin_li_1997_crack_bridging_slip_hardening.md (the slip-hardening interface model whose parameters are measured here), li_wang_wu_2001_pva_ecc_tensile_strain_hardening.md (composite-scale application of the oil-coating treatment), li_wu_wang_etal_2002_interface_tailoring_pva_ecc.md (systematic interface tailoring).

Graph implications

• Supports promoting the candidate edge interface_properties -> fiber_bridging_law from candidate toward confirmed once an 02_concepts/interface_properties.md node is created.
• Adds candidate edge interface_properties -> strain_hardening_criteria (fiber rupture by delamination truncates sigma(delta) and violates the strength criterion).
• Adds candidate edge surface_treatment (oil coating) -> interface_properties.

Verification status

• Source note: present.
• Full-text extraction: present.
• Original PDF: present.
• DOI: needs verification.
• Exact numerical values of G_d, t0, beta for coated and uncoated PVA in this paper: needs verification against the original PDF.
• Figure and table numbers: needs verification.