Performance-based optimization of strut-and-tie models in reinforced concrete deep beams

Abstract

This paper presents the performance-based optimization of strut-and-tie models in reinforced concrete deep beams. The performance-based optimization (PBO) technique combines performance-based design concepts with modern topology optimization technologies into a single scheme to automatically generate optimal designs of continuum structures. Developing strut-and-tie models in reinforced concrete deep beams is treated as a topology optimization problem of continuum structures. The optimal strut-and-tie model in a concrete deep beam is generated by gradually eliminating inefficient finite elements from the deep beam in an optimization process. Performance-based optimality criteria are incorporated in the PBO method to identify the optimum from the op-timization process. The PBO technique allows the designer to tailor the structure to a specific performance level. Two examples are provided to demonstrate the effectiveness and validity of the PBO technology in generating optimal strut-and-tie models for the design and detailing of reinforced concrete deep beams.