Cement Concrete Pavement Cut Slit Mechanism

The efficient control of slab cracking that develops in concrete pavements is important to pavement performance. Early-age sawcutting, as one form of crack induction, has been applied to concrete pavement surfaces at specific contraction locations. The stress field in a concrete slab induced by thermal and shrinkage gradients is based on curling and waing analysis, which leads to criteria optimum time of sawcutting. Modified linear elastic fracture mechanics and finite-element method are applied to determine a sufficient notch or sawcut depth to ensure controlled cracking. The fracture parameters K1~ are obtained from laboratory notched beam fracture tests. The theoretical sawcut depth, as determined by fracture analysis, that can be used in pavement construction practice, is significantly less than the conventional depth.