ABSTRACT
Traditionally the durability design of concrete structures is based on implicit rules for materials, material compositions, working conditions, structural dimensions, etc. Examples of such 'deemto-satisfy' rules are the requirements for minimum concrete cover, maximum water/cement ratio, minimum cement content, crack limitation, air content, cement type and coatings on concrete. These rules are sometimes related to the type of environmental exposure such as indoor climate, wet exposure, presence of frost and deicing salts, sea water and so on. The purpose of all these rules has been to secure robustness for structures, although no clear definition for service life has been presented.
