SIDE MEMBER

PURPOSE:To prevent Euler's buckling by forming a side member into a rectangular cross section using a pair of web panels and a pair of flange panels, and forming each web panel with a compression face which is compressed by bending about a strong shaft, and making the width-to-thickness ratio of the web panels greater than that of the flange panels. CONSTITUTION:This side member 1 is formed into a rectangular cross section using upper and lower opposite web panels 2 and right and left flange panels 3. In the figure, X, Y represent the axes of secondary moment of a plane of bending and Tw, Tf represent the thickness of the panels 2 and that of the panels 3, respectively. The web panel 2 on the weak axis of bending is formed with a compression face which is compressed by bending about the strong axis X of secondary moment of a cross section of bending which is more likely to buckle into an accordion shape than the flange panel 3 on the weak axis of bending. The width-to-thickness ratio of the web panels 2, showing the ease with which the panels buckle, is greater than that of the flange panels 3 so that the web panels 2 are easier to buckle than the flange panels 3.