Huang et al. (2020) — Seawater sea-sand Engineered Cementitious Composites...

Citation

Bo-Tao Huang, Jing Yu, Jia-Qi Wu, Jian-Guo Dai, Christopher KY. Leung (2020). Seawater sea-sand Engineered Cementitious Composites (SS-ECC) for marine and coastal applications. Composites Communications, Vol. 20, Article 100353.

DOI: 10.1016/j.coco.2020.04.019
Atlas layer: extension
Related Victor Li book chapter: Chapter 4: Non-Portland / Sustainable ECC; Chapter 5: Advanced ECC
Source PDF: huang-2020-seawater-sea-sand-engineered-cementitious-composites.pdf
Extracted text: atlas/full_text/huang-2020-seawater-sea-sand-engineered-cementitious-composites_full_text.md
Source note: atlas/source_notes/huang-2020-seawater-sea-sand-engineered-cementitious-composites_source_note.md

Why this paper matters

Direct comparative study demonstrating that raw seawater and unwashed sea-sand can be successfully deployed in both normal-strength (PVA fibers, $f_c = 58\text{ MPa}$, $\varepsilon_{tu} = 4\%$) and high-strength (PE fibers, $f_c = 137\text{ MPa}$, $\varepsilon_{tu} = 5\%$) ECC, achieving full performance equivalence with freshwater control mixes.

Main contribution

Formulated and compared normal-strength SS-PVA-ECC ($f_c = 58\text{ MPa}$, $\sigma_{tu} = 5\text{ MPa}$, $\varepsilon_{tu} = 4\%$) and high-strength SS-PE-ECC ($f_c = 137\text{ MPa}$, $\sigma_{tu} = 8\text{ MPa}$, $\varepsilon_{tu} = 5\%$).
Found that seawater accelerates early hydration, shortening setting time by 10–20% and boosting 28-day compressive strength by 12% in fly ash-rich PVA mixes.
Confirmed that high-strength SS-PE-ECC exhibits virtually identical compressive and direct tensile behavior to freshwater washed-sand ECC.

Evidence summary

Normal-strength PVA-ECC: Seawater mix achieved $f_c = 58.2\text{ MPa}$ (+12%), $\sigma_{tu} = 5.0\text{ MPa}$, $\varepsilon_{tu} = 4.0\%$ (vs Freshwater control $52.0\text{ MPa}$, $5.3\text{ MPa}$, $4.9\%$) (Figs. 4, 5).
High-strength PE-ECC: Seawater mix achieved $f_c = 136.8\text{ MPa}$, $\sigma_{tu} = 8.0\text{ MPa}$, $\varepsilon_{tu} = 5.0\%$ (equivalent to Freshwater control $137.1\text{ MPa}$, $8.1\text{ MPa}$, $5.0\%$).
Setting time: 10–20% shorter due to dissolved seawater salts ($C_3S$ hydration acceleration).

Linked Atlas nodes

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

Claim-evidence rows to add

Atlas node	Claim	Evidence summary	Page/Figure/Table	Status
`04_material_systems/green_ecc.md`	Normal-strength SS-PVA-ECC (58 MPa fc, 4% strain) and high-strength SS-PE-ECC (137 MPa fc, 5% strain) achieve complete parity with freshwater controls.	Experimental benchmarking showed 137 MPa compressive strength and 5% tensile strain in seawater PE-ECC.	Pages 1, 3-4, Section 3, Figs. 4, 5	verified_from_pdf
`04_material_systems/green_ecc.md`	Dissolved salts in seawater accelerate hydration, reducing setting times by 10–20% and increasing 28d compressive strength of fly ash-rich ECC by 12%.	Setting time decreased by 10–20% and normal-strength ECC strength rose from 52.0 to 58.2 MPa.	Pages 3-4, Section 3, Figs. 3, 4a	verified_from_pdf

Verification status

PDF preserved: yes (huang-2020-seawater-sea-sand-engineered-cementitious-composites.pdf)
Text extracted: yes (atlas/full_text/huang-2020-seawater-sea-sand-engineered-cementitious-composites_full_text.md)
DOI verified: yes (10.1016/j.coco.2020.04.019)
Page/figure/table verified: yes
Claim-evidence matrix ready: yes

Cautions

Presence of seawater salts necessitates non-ferrous reinforcement (e.g. FRP bars).