Shear capacity of tapered web panel of plate girders with web opening

Abstract

Tapered plate girders with web openings are widely used to route services and reduce weight, yet current provisions only partly capture the combined effects of tapering angle, opening size, panel aspect ratio, and web slenderness. A total of 115 shell finite-element (FE) models were analysed. The FE model was verified against measurements from seven tested tapered girders with web openings and then used in a full-factorial parametric study augmented to assess opening-shape effects. The verified model reproduced the experimental response and shows consistent trends. Capacity falls as the panel aspect ratio, web opening ratio and web slenderness ratio increase, while the tapering angle showed a beneficial influence within the investigated range, improving the web shear capacity in the presence of web openings. Based on the numerical dataset, an EC3-aligned mechanics-based equation was developed for direct shear-capacity prediction. The equation incorporates web slenderness, opening ratio, panel aspect ratio, and tapering angle, and its coefficients were obtained using nonlinear regression of the FE database. The calibrated model provides accurate predictions with good agreement with the FE results. Overall, the work links experiment, simulation, and design to give a more reliable basis for sizing tapered girders with web openings.