High-cycle fatigue life prediction of reinforced concrete deep beams

The strut and tie method was modified to predict the fatigue life of the deep beams tested by modifying the constitutive models and effectiveness factor of concrete with fatigue damage models. To achieve this, the irreversible compressive fatigue strain in concrete is considered as a pseudo-load. The crack initiation life and the progressive crack growth of steel reinforcement are accounted for using strain-life models and linear elastic fracture mechanics, respectively. Within the developed algorithm, failure will occur when one of the evolving forces in either the concrete strut or steel reinforcement approaches the corresponding residual resistance capacity.