ACI 207.2R

Description / Abstract: This report is primarily concerned with evaluating the thermal behavior of mass concrete structures to control the cracking in members that occurs principally from thermal contraction with restraint. This report presents a detailed discussion of the effects of heat generation and volume changes on the design and behavior of mass concrete elements and structures, a variety of methods to compute heat dissipation and volume changes, and an approach to determine mass and surface gradient stresses. It is written primarily to provide guidance for the selection of concrete materials, mixture requirements, and construction procedures necessary to control the size and spacing of cracks. The quality of concrete for resistance to weathering is not emphasized in recommending reduced cement contents; however, it should be understood that the concrete should be sufficiently durable to resist expected service conditions. This report can be applied to most concrete structures with a potential for unacceptable cracking. Its general application has been to massive concrete members 18 in. (460 mm) or more in thickness; it is also relevant for less massive concrete members.