Schubverhalten von Biegebauteilen ohne Querkraftbewehrung

Shear response of reinforced concrete members without stirrups under bending

This contribution presents a new model to determine the shear capacity of reinforced concrete members under bending without shear reinforcement. The main idea of the model is the consideration of principal stress in the region of crack tips of the flexural cracks due to bending. A potential band for the formation of a critical shear crack that tends to connect the tips of existing flexural cracks can be assumed. The width of this band decreases with the increasing of the bending moment and gets larger when the shear force becomes higher. This means the bending moment affects positively the shear capacity. With the new model the shear capacity and the crack pattern in previous shear tests with different structural systems and loading conditions can be explained, which is generally not possible with the existing models.