Majority of concrete structures are subjected to fatigue loading. It is important to math- ematically model fatigue in order to predict the remaining life of these structures. Fatigue crack propagation is a complex and irreversible process, hence an energy approach…
Majority of concrete structures are subjected to fatigue loading. It is important to math- ematically model fatigue in order to predict the remaining life of these structures. Fatigue crack propagation is a complex and irreversible process, hence an energy approach is adopted in this work by using thermodynamics as the framework. In thermodynamics, a dissipation potential is used to describe the evolution of internal variables of a dissipative phenomenon. An analytical expression for dissipation potential defined for fatigue crack propagation in concrete is derived using the concepts of dimensional analysis and self-similarity. A fatigue crack propagation model is obtained using this potential as a guideline and is validated using available experimental results. An attempt is made to impart physical meaning to this potential and also to the various dimensionless products involved. It is shown that the proposed expression for dissipation potential captures size effect in concrete and therefore resulting in more objective results.