Date of Publication :16th September 2022

Abstract: Beams with large depth in relation to span are known as deep beams. Transfer girders, offshore structures and deep foundations frequently employ deep beams. An established design technique for dealing with D-regions (Discontinuous regions) is the strut-and-tie model. The Strut-and-Tie modeling approach is an analysis and design tool for reinforced concrete elements which assumes that internal stresses in a member are transferred through a truss mechanism. The tensile ties and compressive struts connected by nodal zones form the truss members. The truss idealized by strut-and-tie model indirectly account for distribution of both shear and flexure. A diaphragm in a box girder bridge forms the component in a box girder bridge which strengthens the box girder with respect to torsion and transmits shear to the bearings. Due to the diaphragm having a small span-to-depth ratio and presence of a discontinuity (opening) makes it a D-region. Due to a lack of experience with the design process, the difficulty to validate truss models (using a finite element model), and the length of time it takes to perform strut and tie model design and analysis, bridge architects have yet to fully comprehend the strut and tie model. Consequently, a well defined strut and tie modeling technique will help bridge designers feel more at ease using the design method. This paper presents a uniform design procedure for employing strut-and-tie model for box girder diaphragms that can be practiced by designers

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