Ultra-High Ductility Concrete Giving Structures Ductility

ECC (Engineered Cementitious Composite) is a high-ductility material produced by introducing high-strength, high-modulus PVA fibers into a cementitious matrix and optimizing the fiber, matrix and interface relationship through micromechanics. Under tensile loading it does not form a single through-going crack; instead it develops numerous fine microcracks while continuing to carry load, showing clear strain hardening. Ultimate tensile strain can reach 3%–12%, more than 100 times that of ordinary concrete.

Compared with ordinary and fiber-reinforced concrete, the core value of ECC is that it cracks without failing: crack width can be reliably held below 100 μm, effectively blocking the ingress of water, chloride ions and carbon dioxide, and markedly improving durability under harsh conditions such as freeze–thaw, wet–dry cycling and de-icing salts.

The material offers good self-compacting and pumping performance. It can be used both for strengthening and repair of existing structures and for crack-resistant, waterproof locations in new works, with thin application thickness, low added load and controllable impact on the original structure.