Quantifying Longitudinal, Corner and Transverse Cracking in Jointed Concrete Pavements

Mechanistic analysis of jointed concrete pavements has traditionally been performed by analyzing the pavements under either traffic loading or combined environmental and traffic loading. The environmental loading analysis is often limited to a linear temperature differential through the slab and the traffic loading is often reduced to a single or dual wheel load positioned at a free slab edge. This type of analysis usually predicts bottom-up transverse cracking in the center of the slab. However, some field data has indicated that this is often not the failure mode in rigid pavements as corner cracking and longitudinal cracking can also occur. A fatigue analysis using stresses predicted for the edge loading case under a positive temperature gradient will therefore give misleading results. This paper shows that the failure mode of rigid pavements can be transverse cracking, corner cracking or longitudinal cracking originating at either the top or bottom of the slab, depending on the slab geometry, concrete properties, environmental conditions and traffic loading. This indicates that a rigorous finite element analysis of a concrete pavement investigating all possible failure modes is required for a deterministic fatigue analysis based on concrete tensile stresses.