Jin et al. (2022) — Mechanical Properties of Slag-Based Cementless Composites According to Types of Polyethylene Fibers
Citation
Jin, J.-E., Choi, J.-I., Park, S.-E., & Lee, B. Y. (2022). Mechanical Properties of Slag-Based Cementless Composites According to Types of Polyethylene Fibers. Journal of the Korean Recycled Construction Resources Institute, 10(3), 243–251.
- DOI:
10.14190/JRCR.2022.10.3.243 - Atlas layer: extension
- Related Victor Li book chapter: Chapter 3: Fiber/Matrix Interfacial Micromechanics & Chapter 7: Alternative Reinforcing Fibers (PE Fibers) & Chapter 9: Green ECC
- Source PDF:
jin-2022-mechanical-properties-of-slag-based.pdf - Extracted text:
full_text/jin-2022-mechanical-properties-of-slag-based_full_text.md - Source note:
source_notes/jin-2022-mechanical-properties-of-slag-based_source_note.md
Why this paper matters
Directly resolves the competition between fiber tensile strength and fiber aspect ratio in ultra-ductile cementless composites, proving that an 8.3 % increase in PE fiber aspect ratio ($l_f/d_f = 1500$ vs. 1385) improves tensile strain capacity by 11.7 % (reaching 7.50–7.82 %), enhances energy absorption toughness by 12.4 %, and tightens crack widths by 9.1 %, surpassing the influence of a 10.9 % gain in raw fiber tensile strength.
Main contribution
- Formulates three calcium-activated slag (AAS) cementless composite mixtures using GGBFS and solid $\text{Ca(OH)}_2$ (10 wt%) across two PE fiber geometries (PE1: aspect ratio 1500, $\sigma_f = 2700\text{ MPa}$; PE2: aspect ratio 1385, $\sigma_f = 3030\text{ MPa}$) and two $w/b$ ratios (0.30 and 0.32) at 1.50 vol. % fiber dosage.
- Conducts density, ASTM C109 compressive, and JSCE uniaxial dogbone tensile tests after 28 days of water curing.
- Quantifies that PE1 ($d_f = 12\ \mu\text{m}$, aspect ratio 1500) delivers higher tensile strain capacity ($\epsilon_u = 7.50\%$ vs. 6.71 % for PE2) and lower average crack width (59.8 $\mu\text{m}$ vs. 65.8 $\mu\text{m}$) due to an 8.3 % higher specific interfacial contact area.
- Demonstrates that increasing $w/b$ to 0.32 further enhances tensile strain capacity to 7.82 % with saturated micro-cracking and tighter crack widths ($54.2\ \mu\text{m}$).
Evidence summary
- Binder System: 100 % GGBFS (Blaine $4320\text{ cm}^2/\text{g}$) activated with solid powder $\text{Ca(OH)}_2$ (10 wt% of binder).
- PE Fiber Specifications ($V_f = 1.50\text{ vol. \%}$, length 18 mm):
- PE1: $d_f = 12\ \mu\text{m}$, Aspect ratio $l_f/d_f = 1500$, $\sigma_f = 2700\text{ MPa}$, $E_f = 88\text{ GPa}$, density $0.97\text{ g/cm}^3$.
- PE2: $d_f = 13\ \mu\text{m}$, Aspect ratio $l_f/d_f = 1385$, $\sigma_f = 3030\text{ MPa}$, $E_f = 110\text{ GPa}$, density $0.97\text{ g/cm}^3$.
- Mechanical Properties (28-day water cured):
- PE1-30 ($w/b = 0.30$): $f_c = 36.8\text{ MPa}$, $\sigma_u = 8.52\text{ MPa}$, $\epsilon_u = 7.50 \pm 0.62\%$, toughness = $0.435\text{ J/mm}^3$, crack width = $59.8\ \mu\text{m}$.
- PE2-30 ($w/b = 0.30$): $f_c = 35.5\text{ MPa}$, $\sigma_u = 8.85\text{ MPa}$, $\epsilon_u = 6.71 \pm 0.55\%$, toughness = $0.387\text{ J/mm}^3$, crack width = $65.8\ \mu\text{m}$.
- PE1-32 ($w/b = 0.32$): $f_c = 31.8\text{ MPa}$, $\sigma_u = 7.65\text{ MPa}$, $\epsilon_u = 7.82 \pm 0.68\%$, toughness = $0.412\text{ J/mm}^3$, crack width = $54.2\ \mu\text{m}$.
Linked Atlas nodes
02_concepts/strain_hardening_criteria.md02_concepts/fiber_geometry_effects.md04_material_systems/green_ecc.md04_material_systems/pe_ecc.md05_experiments/direct_tensile_test.md04_material_systems/cementless_composites.md
Relationship to Victor Li book
- Extends Victor Li (2019) Chapter 3 (Fiber/Matrix Interfacial Micromechanics) and Chapter 7 (PE Fibers).
- Validates the fundamental micromechanical theorem: when fibers are not prone to rupture (as in slip-hardening PE fibers), higher aspect ratio ($l_f/d_f$) provides a larger specific surface contact area and extends pullout displacement, delivering higher composite ductility and narrower crack widths than higher fiber tensile strength.
Claim-evidence rows to add
| Atlas node | Claim | Evidence summary | Page/Figure/Table | Status |
|---|---|---|---|---|
02_concepts/fiber_geometry_effects.md |
An 8.3 % increase in PE fiber aspect ratio increases composite tensile strain capacity by 11.7 % and reduces crack width by 9.1 % in AAS composite | Direct uniaxial tensile testing comparing PE1 (aspect ratio 1500) vs PE2 (aspect ratio 1385) | Section 3.2, Table 4, Fig. 4-6 | verified_from_pdf |
04_material_systems/pe_ecc.md |
PE-AAS composite with $w/b = 0.32$ achieves direct tensile strain capacity of 7.82 % with crack widths $< 55\ \mu\text{m}$ | JSCE dogbone tensile testing of PE1-32 mixture | Section 3.2, Table 4, Fig. 4 | verified_from_pdf |
Verification status
- PDF preserved: yes (
jin-2022-mechanical-properties-of-slag-based.pdf) - Text extracted: yes (
full_text/jin-2022-mechanical-properties-of-slag-based_full_text.md) - DOI verified: yes (
10.14190/JRCR.2022.10.3.243) - Metadata verified: yes (JRCR, Vol. 10, No. 3, pp. 243–251, 2022)
- Claim-evidence matrix ready: yes
Cautions
- Paste-only mixtures without silica sand; addition of sand will slightly reduce tensile strain capacity while increasing matrix elastic modulus.
- PE fibers with $d_f = 12\ \mu\text{m}$ require careful addition during mixing to ensure homogeneous dispersion.