Modelo analítico para el análisis de la flexión y la fisuración en secciones de hormigón armado como alternativa al diagrama de pivotes

An analytical model is presented in order to study the failure of reinforced concrete sections subjected to bending, based on fracture mechanics concepts applied to concrete. It determines the stress in the reinforcement by introducing an additional compatibility equation that relates the crack opening with the stretching of the reinforcement. The proposed formulation assumes a cohesive behaviour of the fractured concrete introducing a force that depends on the cohesive stresses at the crack tip. Model results are validated against several beam tests. The crack opening and the rotational capacity of reinforced concrete sections can be obtained with the model.