Analysis of Buckling Modes and Critical Buckling Stress of Open-rib Stiffened Plate

In order to master the design and calculation method of open-rib stiffened plate better,the buckling modes and critical buckling stress of four-side simply-supported plate without longitudinal and transverse stiffening ribs,four-side simply-supported stiffened plate with longitudinal stiffening ribs arranged by equal distance,stiffened plate with longitudinal and transverse stiffening ribs arranged by equal distance,were analyzed by elastic stability theory.The results show that critical buckling stress is related to plate width,plate length and plate thickness for four-side simply-supported plate or four-side simply-supported stiffened plate.Critical buckling stress can be improved with the decrease of plate width and plate length,and with the increase of thickness of plate.There are 3kinds of buckling modes of four-side simplysupported stiffened plate with changes of stiffness ratios of stiffening ribs.Stiffening ribs and stiffened plate are overall buckling in mode 1. Wave nodes are formed on stiffening ribs,stiffening ribs and stiffened plate are buckling in mode 2.Stiffening ribs will not appear instable,only stiffened plate is buckling in mode 3.Critical buckling stress increases with the increase of stiffness ratio of the stiffening rib,the increase range is maximal in mode 1,and comes second in mode 2.Critical buckling stress tends to be constant value in mode 3.