CIA CPN24-1990

All concrete structures are subject to permanent contraction movements due to drying and shrinkage, carbonation and creep, as well as transient movements caused by fluctuations in humidity and temperature and the application of loads on the structure. This paper describes how control joints can be used in walls and slabs to concentrate the cracking in preformed grooves. The contraction is accommodated at the control joints, thus the restraint to shrinkage between the joints is largely removed.