High Early Strength ECC

Inventors: V.C. Li and S. Wang
US Patent No. 7,799,127
Issued in September 2010


Performance Targets: 

  • Fast strength gain in ulttra ductile ECC within 4 hours of casting to widen its applications in the construction industry, which demands fast set times

Applications:

  • Overnight Pavement construction and repair, Construction of high-rise structures requiring rapid strength gain in lower stories

Suggested Key Words: High early strength, ECC, fiber, matrix, cement, ductility, composites

Abstract: Rapid repair and retrofit of existing infrastructures demand durable high early strength materials that not only deliver sufficient strength within a few hours of placement but also significantly prolong the maintenance interval. The invention comprises a class of newly developed polyvinyl alcohol (PVA) fiber-reinforced high early strength engineered cementitious composites (ECC) materials featuring extraordinary ductility. The tailoring of preexisting flaw size distribution through non-matrix interactive crack initiators in the composite matrix results in long-term high tensile ductility. The resulting high early strength ECC materials are capable of delivering a compressive strength of 21 MPa (3.0 ksi) within 4 hours after casting and retaining long-term tensile strain capacity above 2%.