Re-Establishment Of Design Formula For Post-Buckling Shear Strength Of Practical Plate Girder

Tóm tắt

A plate web subjected to shear load is well-known for its capability to develop remarkable post-buckling shear strength when two pairs of boundary conditions of the web panel are provided sufficiently. So far, there are some theories and numerous idealizations to explain this behaviour. Still, all of the existing web post-buckling theories need to be revised, and thus, the elusive phenomena during the post-buckling stage remain a great challenge to researchers. By the finite element analysis results combined with the existing experimental shear tests, the previous paper (Mai TH et al, 2017) not only shed light on the weaknesses in the existing theories but also revealed new findings concerning the sources of the web post-buckling reserve. The current paper continuously conducted intensive investigations of the web post-buckling behaviour in the plate I-girders under shear load by a set of models, and the behaviour of intermediate transverse stiffeners was studied simultaneously. Consequently, the current results revealed that the boundary condition behaviour at the junction between transverse stiffeners and web panels depended primarily on the size of web panels (a/D). Next, a new design formula for ultimate shear strength in practical girders was proposed based on the observed results from the set of models. Finally, its accuracy was verified by 48 existing test specimens that possessed slight and moderate flanges.