Investigation of the Rotation Capacity and Flexural Strength of Web-Tapered Hybrid High Strength Steel I-Beams

• Main Author: Ntoni, Chungom N
• Format: Dissertation
• Language: English
• Published: ProQuest Dissertations & Theses 01-01-2020
• Subjects: Civil engineering
• ISBN: 9798557085915

Understanding the behavior of structural steel in terms of fabrication and fashioning is an important factor in the designing of steel structures. The search for structural steel with capabilities of acceptable responses in seismic regions alongside beneficial features such as cost, and efficiency has led to the investigation of the behavior of high strength steels (HSS). These steels have yield strength of 55 ksi (ASTM A572) or higher, as classified by U.S. standards, while their inelastic capacity is less than that of conventional structural steel. The present research investigates the rotation capacity and flexural strength of hybrid high strength web-tapered I-shaped steel beam using an experimentally verified nonlinear finite element modeling technique. The academic multipurpose software package ANSYS19.2 is used to develop a shell finite element model, after the validation using an experimental specimen from a previous study was modeled and validated. The residual stresses are associated with the finite element model for different welding configurations. Geometrical imperfections are applied to conduct a linear eigenvalue analysis and to capture buckling mode shapes to perform a nonlinear buckling analysis. The aim is to capture local, overall, and local-overall interactive buckling modes of non-prismatic hybrid high strength I-sections. A comprehensive parametric study is performed by varying the cross-section dimension, flange and web slenderness ratio, and grade of steel for flange and web to cover a wide range of parameters to identify the correlation between slenderness, ductility, and member resistance. The results will be used to propose design equations that could be used in the direct computation of desired parameters in the design of web variable hybrid and homogeneous members during structural designing.