Park et al. (2022) — PE-PVA Hybrid SHCC in Natural Weathering vs Underwater Conditions
Citation
Se-Eon Park, Huy Hoàng Nguyễn, Jeong-Il Choi, Bang Yeon Lee, Yun Yong Kim (2022). Comparison of Mechanical and Crack-Healing Properties of PE-PVA Hybrid Fiber-Reinforced SHCCs in Natural and Underwater Conditions. Materials, 15 (18), 6339.
- DOI:
10.3390/ma15186339 - Atlas layer: extension
- Related Victor Li book chapter: Chapter 8: Self-Healing and Durability (Section 8.4)
- Source PDF:
primary_data/park-2022-comparison-of-mechanical-and-crack-healing.pdfIJP06622E_Comparison of self healing_materials.pdf` - Extracted text:
secondary_data/full_texts/park-2022-comparison-of-mechanical-and-crack-healing_full_text.mdsecondary_data/full_texts/IJP06622E_Comparison of self healing_materials_full_text.md` - Source note:
secondary_data/source_notes/park-2022-comparison-of-mechanical-and-crack-healing_source_note.mdsecondary_data/source_notes/IJP06622E_Comparison of self healing_materials_source_note.md`
Why this paper matters
Provides a direct 1:1 comparison of low-fiber (1.35 vol. %) rubberized PE-PVA hybrid SHCC (1.25 % PE + 0.10 % PVA, 50 % slag, 10 % crumb rubber) cured under laboratory underwater submersion versus outdoor natural weathering. Proves that both environments sustain ultra-high direct tensile ductility (8.00 % vs 7.74 %) and post-healing reloading strength (7.72 vs 7.54 MPa), while underwater submersion achieves a complete crack-healing threshold of $60\ \mu\text{m}$ (38.6x higher healing rate than outdoor weathering).
Main contribution
- Robust Tensile Ductility in Natural Weathering: Proved that outdoor field weathering sustains a direct tensile strain capacity of $7.74 \pm 0.63\text{ \%}$ and tensile strength of $7.60\text{ MPa}$ ($f_c = 40.6\text{ MPa}$), only 3–4 % lower than underwater controls ($8.00\text{ \%}$, $7.93\text{ MPa}$, $f_c = 45.1\text{ MPa}$).
- Quantified Crack-Healing Gap: Established that underwater immersion achieves a complete crack sealing threshold of $60\ \mu\text{m}$ (healing rate $\gamma_r$ 38.6x higher), whereas natural rainfall is insufficient to fully close cracks $>50\ \mu\text{m}$ on the exterior surface.
- Reloading Mechanical Performance Retention: After 28-day healing following 3.0 % tensile strain damage, reloading verified nearly 100 % tensile strength retention ($7.72\text{ MPa}$ for underwater, $7.54\text{ MPa}$ for outdoor) with residual strain capacity of $\approx 5.8\text{ \%}$.
Evidence summary
- 28-Day Direct Tensile Performance:
M-W(Underwater): $\epsilon_c = 8.00 \pm 0.69\text{ \%}$, $\sigma_{tu} = 7.93 \pm 0.62\text{ MPa}$, $\sigma_{fc} = 3.74\text{ MPa}$, $f_c = 45.1\text{ MPa}$, Toughness = $0.46\text{ MPa}\cdot\text{m/m}$ (Tables 5 & 6, Pages 6–8).M-O(Outdoor): $\epsilon_c = 7.74 \pm 0.63\text{ \%}$, $\sigma_{tu} = 7.60 \pm 0.31\text{ MPa}$, $\sigma_{fc} = 3.13\text{ MPa}$, $f_c = 40.6\text{ MPa}$, Toughness = $0.41\text{ MPa}\cdot\text{m/m}$.- Autogenous Crack Healing (3.0 % pre-strain):
M-W: 100 % crack closure for $W_c \le 60\ \mu\text{m}$; $\gamma_r$ was 38.6x higher than M-O (Figs. 6–8, Pages 9–11).M-O: Surface healing products washed away by rain; limited exterior sealing.- Stiffness & Reloading Tensile Recovery:
- 28-day RF recovery: +27 %p (M-W) vs +12 %p (M-O) (Fig. 9, Page 12).
- Post-healing tensile strength: $7.72\text{ MPa}$ (M-W, 97.4 %) vs $7.54\text{ MPa}$ (M-O, 99.2 %) with $\epsilon_{c-h} \approx 5.8\text{ \%}$ (Table 7 & Figs. 10–11, Pages 12–14).
Linked Atlas nodes
04_material_systems/self_healing_ecc.md04_material_systems/green_ecc.md05_experiments/crack_width_distribution.md05_experiments/direct_tensile_test.md
Relationship to Victor Li book
- Primary book anchor remains Victor Li (2019), Engineered Cementitious Composites (ECC).
- Directly extends Chapter 8 (Self-Healing and Durability, Section 8.4) by quantifying the difference between laboratory immersion and field weathering in Green SHCC, proving that 7.74 % direct tensile ductility and 7.54 MPa reloading tensile strength are robustly preserved outdoors.
Claim-evidence rows to add
| Atlas node | Claim | Evidence summary | Page/Figure/Table | Status |
|---|---|---|---|---|
04_material_systems/green_ecc.md |
Hybrid PE-PVA SHCC exposed to outdoor weathering retains 7.74 % direct tensile strain capacity and 7.60 MPa tensile strength | Direct tension tests verified $\epsilon_c = 7.74\text{ \%}$, $\sigma_{tu} = 7.60\text{ MPa}$, and $f_c = 40.6\text{ MPa}$ under natural exposure | Page 6339:1 & 7 / Table 5 / Fig. 4 | verified_from_pdf |
04_material_systems/self_healing_ecc.md |
Underwater immersion achieves a 60 $\mu\text{m}$ complete crack closure threshold, exhibiting 38.6x higher healing rate than natural outdoor exposure | Crack width measurements confirmed complete closure up to $60\ \mu\text{m}$ for M-W | Page 6339:1 & 10 / Figs. 6, 7, 8 | verified_from_pdf |
04_material_systems/self_healing_ecc.md |
Post-healing reloading confirms nearly 100 % tensile strength retention (7.54–7.72 MPa) and 5.8 % residual ductility in both curing environments | Reloading after 28-day healing recorded $f_{ts-h} = 7.72\text{ MPa}$ (M-W) and $7.54\text{ MPa}$ (M-O) | Page 6339:12 & 14 / Table 7 / Figs. 10, 11 | verified_from_pdf |
Verification status
- PDF preserved: yes (in
primary_data/IJP06622E_Comparison of self healing_materials.pdf) - Text extracted: yes (PyMuPDF, 16 pages)
- DOI verified: yes (
10.3390/ma15186339) - Page/figure/table verified: yes (all checked in PDF text)
- Claim-evidence matrix ready: yes
Cautions
- Outdoor weathering does not achieve complete surface sealing for cracks $>50\ \mu\text{m}$ due to rainwater leaching and lack of continuous moisture.