A compound strip method based on the Mindlin plate theory for static and buckling analyses of thin-walled members with transverse stiffeners

The compound strip method origins from the finite strip method (FSM) aimed to analyze thin-walled members with additional parts such as bolts and stiffeners. Traditionally, FSM mainly solves the buckling problem of prismatic members with longitudinally uniform sections. However, existing FSM could not take into account the stiffeners' effect in the present form. The paper proposes a compound strip method based on the Mindlin plate theory (MCSM), in which members are modeled by finite strips while stiffeners are by MITC4 shell elements. This combination can effectively connect the stiffeners with the flange/web of the members. Meanwhile, the contribution from the thickness of stiffeners to buckling strengths could be considered accurately. The validity of MCSM is demonstrated through the comparison of the deformation and capacity from static and buckling analyses with solutions of the finite element method (FEM). The developed MCSM is then used to explore the impact of the number and thickness of stiffeners on the members. Besides, the discussion on how sectional characteristics affect stiffeners in improving the buckling loads is carried out. To ensure the calculation in MCSM is accurate and efficient, a study on meshing schemes is also presented.