Cracks in concrete structures can indicate major structural problems and detract from the appearance of monolithic construction. There are many specific causes of cracking. This report presents the principal causes of cracking and a detailed discussion of crack-control procedures. The report consists of eight chapters designed to help the engineer and the contractor in developing crack-control measures.
This report is an update of previous committee reports (ACI Committee 224 1972, 1980, 1990). ACI Bibliography No. 9 supplemented the original ACI 224R (1971). The Committee has also prepared reports on the causes, evaluation, and repair of cracking, ACI 224.1R; cracking of concrete in direct tension, ACI 224.2R; and joints in concrete construction, ACI 224.3R.
In this revision of the report, Chapter 2 on crack mechanisms has been revised extensively to reflect the interest and attention given to aspects of fracture mechanics of concrete during the 1980s. Chapter 3 on drying shrinkage has been rewritten. Chapter 4 has been revised to include updated information on crack-width predictive equations, cracking in partially prestressed members, anchorage zone cracking, and flexural cracking in deep flexural members. Chapter 6 on concrete overlays has been reorganized and revised in modest detail to account for updated information on fiber reinforcement and on polymer-modified concrete. Chapter 7 on mass concrete has been revised to consider structural consequences more extensively.