Study on Pipe Strut Dimensions Optimization for Strutted Box Girder Bridge Using FEM

Abstract

Although the concept of a concrete box girder bridge with strutted wing slabs was proposed long ago as a means to expand the width of bridge sections without significantly increasing the self-weight of the superstructure, research on this structural system remains limited. Using data from a full-scale box girder bridge experiment conducted as part of the Ring Road II Viaduct Project in Vietnam, a finite element model was developed to investigate the influence of the steel struts' geometrical dimensions on the structural behavior of box girders. This paper examines key structural responses, including deflection, stress in the concrete slab, and stress in the steel struts, under varying steel strut dimensions—namely, thickness and diameter. The findings reveal that the diameter and thickness of the steel struts significantly affect beam deflection and strut stress, while their impact on slab stress is negligible. Furthermore, the paper provides practical recommendations for selecting optimal steel strut dimensions and highlights future research directions to enhance the design of such structures. These insights aim to benefit both practicing engineers and researchers in the field