As concrete hardens, internal stresses can result in the formation of random, uncontrolled cracks in portland cement concrete (PCC) pavements. Joints are cut to release some of these early-age stresses and to avoid uncontrolled cracking. This brief describes research the Hub is conducting to ultimately find the answer to an important question: What is the latest time (also known as the level of maturity) before which pavement joints must be cut to avoid the generation of random cracks? MORE.