ABSTRACT
Abstract By adopting the holistic approach, a new model is proposed to explain the concrete damage induced by delayed ettringite formation (DBF). This model is based on three essential elements: late sulfate release, microcracking, and exposure to water. Late sulfate release from a cement with high sulfate content (especially that with high content of clinker sulfate in less available form) can cause the delayed deposition of ettringite in pre-existing microcracks after sulfate ions diffuse through the pore solution in concrete, either intermittently, or continuously exposed to environmental water. Microcracking may be promoted by alkali-silica reaction, steam curing at high temperatures, localized high stress in prestressed structures or other causes.
