Evaluation of Rotation Capacity of I-shaped Welded Steel Plate Girders

Abstract

Flexural ductility in steel sections is required to accommodate inelastic force redistribution. It is used to evaluate available inelastic performances of structures. Various factors that influence ductility of the section are compactness, material properties, and lateral support configuration close to plastic hinge region. This paper attempts to evaluate inelastic rotation response of hybrid and homogeneous I-sections considering the influence of above factors. An experimentally verified nonlinear finite element modeling technique is employed to carry out parametric studies to evaluate the extent of influence of the above parameters on rotation response. An attention is given to the interaction between local and lateral buckling and their influence on inelastic rotation for the members subjected to constant moment loading. Regression analysis of the database parametric studies resulted into an equation for evaluation of rotation capacity of I-shaped steel plate girders. The equation is validated by applying it to selected experiments conducted by various researchers. Results of the proposed equation are compared with the rotation capacity prediction equations by others. Statistical analysis of validation study shows that the proposed equation provides refined results as compared to available equations. A flowchart and solved example for the demonstration of the use of proposed equation along with stable length equations are presented.