04.10: Analysis of stiffened curved panels in compression: A preliminary numerical study for experimental tests

Abstract

ABSTRACTThe use of different kinds of curved steel panels in bridge design has been increasing in the past few years, but the design recommendations and the knowledge in this field remain scarce. Taking in account the fact that very few experimental tests on life size curved panels have been carried out so far, an experimental study on stiffened and unstiffened curved panels in compression is planned in the near future. For this purpose, a preliminary numerical study on curved panels was conducted, in order to establish an appropriate experimental test setup. This paper deals with a parametric study on stiffened and unstiffened transversally curved steel panels subjected to pure in‐plane compression performing linear buckling analysis (LBA) and fully nonlinear analysis with geometric imperfections (GMNIA). Considering that the shell‐like structures are highly sensitive to initial imperfections, which significantly lowers their ultimate strength, a linear bifurcation analysis is performed first in order to get the buckling modes of the analysed panels. The buckling shapes are later used as equivalent geometric imperfections in the nonlinear analysis, based on the rules given by EN1993‐1‐5. Furthermore, a finite element analysis, considering geometric and material nonlinearity with initial imperfections, is conducted in ABAQUS software. Simply supported, transversally curved and longitudinally stiffened panels are analysed in order to determine their resistance to pure in‐plane compression. A large parametric study is performed to evaluate the effects of different parameters on the ultimate resistance of the panel. Panels that differ in curvature, aspect ratio and stiffness of the stiffeners are studied. Finally, the numerical results of the parametric study on all, the unstiffened, longitudinally stiffened, both curved and flat panels with the same dimensions are compared. Effects of panel curvature on the critical elastic stress and the ultimate resistance are presented.