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In terms of material constituents, ECC employed similar constituents like fiber reinforced concrete (FRC). It includes water, cement, sand, fiber, and some popular chemical and mineral admixtures. Coarse aggregates were not used which tends to adversely affect the ductile properties of the composite. Unlike some high performance fiber reinforced concrete, ECC does not contain high percentage of fiber. Generally, 2% of discontinuous fiber by ECC volume fraction or lesser is suitable. Due to the relatively little amount of fibers and its chopped shape, the mixing procedure of ECC is identical to those used in mixing process of normal concrete. Many types of fiber could be utilized in ECC, but the detail composition must confirm the certain rules assumed with micromechanics requirements. This means that the matrix, fiber, and the interface between them (mechanical and geometric) properties must be in a proper combination in order to obtain a wonderful properties of ECCs. Finally, ECC designs are followed by micromechanical principles.

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Kawa O. is a structural engineer who has a B.Sc in Civil Eng. and M.Sc in Structural Eng. He works as a lecturer in FOCSIV. He is interested in Structural Concrete Design.Diyar N. has finished his B.Sc in Civil Eng. and M.Sc in Structural Eng. He has published 3 books and 3 articles on various topics. He is a lecturer at Cihan University-Erbil.

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