General requirements of aggregates for use in concrete

Although most issues related to frost resistance of concrete are associated with damage emanating from the paste (e.g., due to internal disruption or surface scaling), there are cases where the aggregates, themselves, either exhibit distress or cause distress of the surrounding paste. This section discusses the basic mechanisms responsible for this aggregate-related distress and describes the manifestations of such distress in field concrete, such as pop-outs and durability cracking (D-cracking). Particular emphasis is placed on discussing the aggregate characteristics, such as pore size distribution, total porosity, and size, that have most impact on frost resistance. Some information is also provided on how to identify those aggregates that may lead to poor frost resistance.