Nonlinear strut-tie model approach in structural concrete deep beams

This paper presents an analysis of reinforced concrete deep beams tested to failure. A nonlinear strut-tie model approach implemented with an interactive computer graphics program was utilized to evaluate the behavior and strength of the beams. Different types of strut-tie models for the beams were developed based on the compressive principal stress trajectories, actual specimen detailing, and loading and support conditions. It was shown that the proposed nonlinear strut-tie model approach in the present study could provide simple and effective solutions for a large number of analysis situations by describing the essential aspects of structural behavior and predicting the strength of structural concrete. It also allows for the conceptual representation of the complex interactions of concrete and reinforcing steel, and permits the -study of localized effects through the nodal zone concept. The framework provided by this nonlinear strut-tie model approach for handling combined actions across the entire range of structural concrete is a strong endorsement for its use with structural concrete deep beams.