Alkali-Silica Reaction and Delayed Ettringite Formation in Concrete: A Literature Review Technical rept. (9/2/2000-8/31/2001)

摘要

Recently in Texas, there has been significant damage of field structures resulting from concrete durability problems. Alkali-silica reaction (ASR) and delayed ettringite formation (DEF), or combinations of the two, have been found to be the main causes of these problems. The term Premature Concrete Deterioration (PCD) has been adopted to refer to problems associated with ASR and DEF because it is often difficult to distinguish between them. The Texas Department of Transportation (TxDOT) has designated nine mitigation options that are available to prevent or minimize PCD-related problems. Research is currently underway to document the performance of concrete using these mitigation options in the laboratory and in the field. One of the objectives of this research is to review the state of the art regarding ASR and DEF, with particular attention to mechanisms of damage, appropriate test methods, specifications, and performance-related issues.