Extreme Ductility and UHP-ECC

1. Learning objectives

• Trace the extreme-ductility ECC lineage.
• Explain PE/UHMWPE, matrix tailoring, and flaw design.
• Distinguish high strength from high ductility.

2. Key concepts

• Extreme ductility
• UHP-ECC
• PE/UHMWPE
• Matrix toughness
• Flaw tailoring
• DP vs DR fibers

3. Minimal theory

Extreme ductility depends on robust bridging across many cracks. High compressive strength alone is insufficient; interface, matrix toughness, and flaw structure must support crack multiplication.

4. Source-grounded evidence

• Node: 02_concepts/extreme_ductility_ecc.md.
• Matrix: 07_visualization/extreme_ductility_extension_claim_evidence_matrix.csv.
• Lab card: 06_lab_position/low_fiber_egc_position.md.

5. Representative papers

• Choi 2016 PE-AASC.
• Ding 2018 UHP-ECC/UHDCC.
• Luong 2023 extremely ductile AAS composite.
• Chen 2026 UHMWPE mechanism.

6. Figures/tables to show later

• Tensile curves at 4%, 8%, 13%, 22%.
• DP vs DR fiber schematic.
• Matrix toughness tradeoff chart.

7. Discussion questions

1. Why does UHMWPE often enable high ductility?
2. Can a very dense matrix reduce ductility?
3. How can flaws improve ductility?

8. Assignment idea

Build a one-page lineage from PVA-ECC to one extreme-ductility EGC material.

9. Linked Atlas nodes

• 02_concepts/extreme_ductility_ecc.md
• 02_concepts/flaw_design.md
• 04_material_systems/high_strength_ecc.md

10. Suggested reading path

1. 02_concepts/extreme_ductility_ecc.md
2. 06_lab_position/low_fiber_egc_position.md

Evidence files

• 07_visualization/foundational_papers_claim_evidence_matrix.csv
• 07_visualization/extreme_ductility_extension_claim_evidence_matrix.csv
• 07_visualization/sustainable_ecc_extension_claim_evidence_matrix.csv
• 07_visualization/by_lee_lab_publications_claim_evidence_matrix.csv