Abstract
For many years member with varying cross-sectional dimensions along the length have been widely used in steel structures. The use of nodal braces to enhance the load-carrying capacity and stability of these elements is prevalent. These supports ensure structural stability by regulating the distribution of loads within the structural system while also enhancing the structure's resistance to lateral loads. Presently, the design of these nodal braces are carried out according to requirements outlined in Design Guide 25 and AISC Specification (2022). However, these standards offer a general framework for elements with fixed brace conditions and prismatic cross-section.
This study aims to be a pioneering investigation into the variation of brace force values in short-span and compact web-tapered beams under different loading conditions. The article seeks to comprehensively examine the requirements and limits of brace force in short-span web-tapered compact beams. To achieve this goal, parametric finite element analyses is utilized to explore how brace force changes concerning beam geometry, material properties, and loading conditions.
The beam used was considered as doubly symmetric and divided into 100 nodes and supported by a nodal brace at the middle node. The beam is 50 inches long, tapering from 42 inches to 36.40 inches over its span of 100 nodes. In terms of finite element analysis, the software utilized significantly influences the accuracy and reliability of results, particularly in scenarios involving inelastic nonlinear analysis. In this study, the Abaqus program was employed specifically to conduct parametric finite element analyses, considering the complexities of inelastic material behavior.
The findings of this research are intended to contribute to the development of a new design method for determining the requirements and limits of brace force in short-span and variable cross-sectional dimension compact beams. Consequently, the aim is to enable the safe and economical design of such beams, providing engineers with ideas to consider and data to utilize in their designs.