Development of High Early Strength ECC

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 maintenance interval. A new type of PVA ECC with high early strength is developed in the project. While micromechanics was applied in many aspects of the material design process, emphasis of this paper is put on the tailoring of pre-existing flaw size distribution in matrix for high tensile ductility. The resulting high early strength ECC materials are capable of delivering compressive strength of 21 MPa within 3-4 hours after placement and retain long-term tensile strain capacity above 2%.

Fig 1. Tensile stress strain relation of HES ECC