Nguyen et al. (2023) — Mechanical and autogenous healing properties of high-strength...

Citation

Huy Hoàng Nguyễn, Phương Hoàng Nguyễn, Quang-Hiếu Lương, Weina Meng, Bang Yeon Lee (2023). Mechanical and autogenous healing properties of high-strength and ultra-ductility engineered geopolymer composites reinforced by PE-PVA hybrid fibers. Cement and Concrete Composites, Vol. 142, Article 105155.

DOI: 10.1016/j.cemconcomp.2023.105155
Atlas layer: extension
Related Victor Li book chapter: Chapter 4: Special ECCs / Geopolymers; Chapter 7: Self-Healing and Durability
Source PDF: nguyen-2023-mechanical-and-autogenous-healing-properties.pdf
Extracted text: atlas/full_text/nguyen-2023-mechanical-and-autogenous-healing-properties_full_text.md
Source note: atlas/source_notes/nguyen-2023-mechanical-and-autogenous-healing-properties_source_note.md

Why this paper matters

Develops cost-effective high-strength ultra-ductility engineered geopolymer composites (HSUD-EGCs) using slag-fly ash binders and 1.5 vol% PE-PVA hybrid fibers, achieving up to 87 MPa compressive strength with 10.51% tensile strain capacity in slag-dominant mixes, and 50 MPa compressive strength with 11.99% tensile ductility in fly ash-dominant mixes with demonstrated autogenous C-(N)-A-S-H crack healing.

Main contribution

Synergized hydrophobic PE and hydrophilic PVA fibers (1.5 vol% total, 2:1 and 1:2 ratios) in high-sand ($s/b = 1.0$) geopolymer matrix.
Achieved $87.0\text{ MPa}$ compressive strength with $10.51\%$ ductility (S-PE) and $50.0\text{ MPa}$ with $11.99\%$ ductility (F-PE).
Evaluated autogenous crack healing at 3% preloading strain, identifying C-(N)-A-S-H precipitation as the healing mechanism.

Evidence summary

Compressive strength: $f_c = 86.5\text{--}87.0\text{ MPa}$ (S series) and $49.5\text{--}50.0\text{ MPa}$ (F series) (Table 4, page 2, Fig. 3).
Direct tensile properties:
S-PE (Slag-rich): $\sigma_{tc} = 3.70\text{ MPa}$, $\sigma_{tu} = 6.64 \pm 0.23\text{ MPa}$, $\varepsilon_{tu} = 10.51 \pm 0.34\%$, 84.3 cracks, crack width $100.3\ \mu\text{m}$.
F-PE (FA-rich): $\sigma_{tc} = 2.70\text{ MPa}$, $\sigma_{tu} = 5.18 \pm 0.08\text{ MPa}$, $\varepsilon_{tu} = 11.99 \pm 0.31\%$, 74.7 cracks, crack width $128.4\ \mu\text{m}$.
S-PVA: $\sigma_{tu} = 6.04\text{ MPa}$, $\varepsilon_{tu} = 6.79\%$; F-PVA: $\sigma_{tu} = 4.60\text{ MPa}$, $\varepsilon_{tu} = 10.35\%$ (Table 5, page 3, Fig. 4).
Cost effectiveness: Replaces high-cost PE with PVA (1/5 price of PE), significantly enhancing economic feasibility (Table 7, Fig. 7).

Linked Atlas nodes

04_material_systems/green_ecc.md
02_concepts/extreme_ductility_ecc.md
04_material_systems/high_strength_ecc.md
05_experiments/direct_tensile_test.md

Claim-evidence rows to add

Atlas node	Claim	Evidence summary	Page/Figure/Table	Status
`02_concepts/extreme_ductility_ecc.md`	Hybrid PE-PVA fiber (1.5 vol%) HSUD-EGC achieves 87 MPa compressive strength with 10.51% tensile strain capacity in slag-rich mixes, and 50 MPa with 11.99% ductility in fly ash-rich mixes.	Direct tensile and compressive tests verified 87 MPa compressive strength and 10.51–11.99% strain capacity.	Pages 1, 3, Section 3.1 & Abstract, Tables 4, 5, Figs. 3, 4	verified_from_pdf
`04_material_systems/green_ecc.md`	Hybridizing 1.0% PE with 0.5% PVA fibers in high-sand (s/b = 1.0) geopolymer matrix provides cost-effective ultra-ductility and autogenous crack healing through C-(N)-A-S-H precipitation.	Cost comparison and SEM/EDS chemical analysis verified cost efficiency and C-(N)-A-S-H healing product.	Pages 1, 4, 6, Section 2.1 & Abstract, Table 5, Table 7, Figs. 6, 8	verified_from_pdf

Verification status

PDF preserved: yes (nguyen-2023-mechanical-and-autogenous-healing-properties.pdf)
Text extracted: yes (atlas/full_text/nguyen-2023-mechanical-and-autogenous-healing-properties_full_text.md)
DOI verified: yes (10.1016/j.cemconcomp.2023.105155)
Page/figure/table verified: yes
Claim-evidence matrix ready: yes

Cautions

Requires 24 h heat curing at 100 °C prior to curing.