Study on role of partition plates in square tube subjected to pure bending

In this paper, the elastoplastic bending collapse of square tube with partition plates subected to statically pure bending is studied by using finite element method (FEM). The roles of partition plates in the bending are investigated. In the case of square tube without partition plate, there are two types of collapse modes in the bending. The first type is a collapse mode due to buckling at the compression side. The second type is a collapse mode due to flattenig of the cross section. It is found that these collapse modes change by adding partition plates. Due to an existence of the partition plates, the collapse is controlled all by the buckling of the partition plate. There are also two types of collapse modes. The former is caused by the buckling of the compression side, and the latter is caused by the flattening of the cross section. The former is superior in energy absorption, and the latter is superior in flexural rigidity.