Macroelement for complete shear behavior of continuous deep girders

The evaluation of the serviceability, safety, and resilience of deep girders in bridges and buildings requires accurate models for their pre- and post-peak shear behavior. This paper purposes such a model formulated as a macroelement for deep shear spans under single and double curvature. The element has two nodes with two degrees of freedom per node (translation and rotation). The paper discusses the formulation of the macroelement based on a three-parameter kinematic theory and provides comparisons with tests. It is shown that the macroelement captures the redistribution of forces in continuous members, and in this way predicts their enhanced ductility as compared to simply supported beams. It is also shown that the model captures the opening of the critical shear cracks under loading. The crack predictions can be compared with field measurements to accurately evaluate the safety of the structure, and in this way to avoid potential costly strengthening measures.