Three-dimensional cohesive crack model prediction of the flexural capacity of concrete slabs on soil

A three-dimensional approach to discretely account for crack initiation, crack growth, and determination of the flexural load capacity of concrete slabs on an elastic foundation under mode I loading is proposed. The finite element model incorporated cohesive crack elements along a pre-defined crack path in the concrete slab. A bilinear softening model was used to describe the stress-crack opening relationship for plain concrete and was defined solely on measured strength and fracture properties. The proposed method predicted the slab’s flexural load capacity as compared to the large-scale experimental concrete slab results for several geometries and notch configurations. The model also provided insight into stress concentration areas and crack propagation positions at different load levels.