Designing Concrete with Self-healing Properties Using Engineered Cementitious Composites as a Model

Abstract

Engineered Cementitious Composites (ECC), also known as Strain Hardening Cement-based Composites, are an easily molded mortar-based composites reinforced with polymer fibers. ECCs are designed based on micromechanics and fracture mechanics theory, to feature large tensile ductility and a variety of unique properties, including tensile properties, superior to other fiber-reinforced composites. The properties of ECCs can be custom-tailored through micromechanics design due to the interaction between the fibers and cement matrix. A structural deterioration of ECC is avoided because the fibers do not allow cracks with large widths to form, unlike conventional concrete. ECCs have the capacity to bend, generating a flexible material. Ductile properties rather than brittle had increased, unlike ordinary concrete, leading to a wide variety of applications. Obtaining superior characteristics for ECC, both in fresh and hardened state, a transition from ECC paste to concrete with self-healing properties was made. To obtain self-healing concrete, with same ECC paste behavior and characteristics, the mix-design of the paste was optimized. The aim of this article is to present the experimental results regarding the transition from ECC paste to self-healing concrete and to analyze the results in order to establish a mix-design pattern for concrete with self-healing properties.