BEHAVIOR OF A WEB PLATE IN SHEAR WITH AN INTERMEDIATE STIFFENER

The behaviour of a simply supported plate with a single stiffener, sub ject to in-plane shear forces, is studied using elastic critical buckl ing analyses and non-linear elasto-plastic finite-element analyses. Pa rticular attention is paid to factors relevant to design of the stiffe ner. Variations in stiffener rigidity, panel side ratio, panel slender ness, and imperfection shapes are considered. A primary conclusion for the panel slendernesses considered is that the stiffener behaviour de pends primarily on moments caused by transverse shear forces in the pa nels on each side of the stiffener, and that the axial force in the st iffener has a relatively small effect. This contrasts with current des ign methods which are based primarily on axial forces resulting from t ension field action. Stiffener requirements based on the analyses are compared with the requirements of current design codes, and rather lar ge differences are found. Large differences between codes are also fou nd. A subsequent paper will use the results presented in developing an d validating a phenomenologically based model for stiffener design.