Optimum Design of Stiffeners in Trapezoidal Load-Bearing Diaphragms in Steel-Box Girders Having a Central Support

Abstract

Stiffeners of Load-Bearing Diaphragms in steel box girders play a crucial role in determining the behavior and ultimate strength of those diaphragms. There is no information on the effect of altering arrangements and sizes of the Stiffeners on the behavior and collapse load of trapezoidal Load-Bearing diaphragms. This paper shows the 3-D numerical model built using Abaqus finite element software, which is capable of stimulating the real behavior of those diaphragms. After establishing validity of the model by comparing it with a previous laboratory experiment, a parametric study is carried out to determine the optimal arrangement and sizes of stiffeners in trapezoidal Load-Bearing Diaphragms that are supported on a single bearing located at the central of the box. Variables in the parametric study are: Breadth/Depth ratio of the diaphragms, the size and arrangement of the stiffeners. The criterion for the comparison is collapse load.