Nonlinear strut-tie model analysis of pre-tensioned concrete deep beams

To date, many studies have been conducted for the analysis and design of disturbed regions. However, prestressed concrete deep beams have not been the subject of much dedicated effort. This paper presents an evaluation of the behavior and strength of two pre-tensioned concrete deep beams tested to shear failure using a nonlinear strut-tie model approach. In this approach, the effective prestressing forces represented by equivalent external loads are gradually introduced along tendon's transfer length in the nearest strut-tie model joints, the friction at the interface of main diagonal shear cracks is modeled by diagonal struts along the direction of the cracks in strut-tie model, and additional positioning of concrete ties at the place of steel ties is incorporated. Through strut-tie model analysis of pre-tensioned concrete deep beams, the nonlinear strut-tie model approach proved to present effective solutions for predicting the essential aspects of the behavior and strength of pre-tensioned concrete deep beams.