ABSTRACT

Bending-tw isting coupling can hard ly be avoided in layered com posites. Its effect on the buckling loads o f curved panels is studied with the aid of the com puter program BEOS. As w ith flat plates, the coupling always reduces the norm al buckling load, w hereas the shear buckling load can be increased or reduced depending on the load d irection. Increasing cu rva tu re results in a greater difference between the buckling loads with and w ithou t coupling, respectively. The buckling load itself, however, grows faster so th a t the relative difference decreases. T hat holds for various fiber d irections, bou n d ary conditions, and stacking sequences. For a lam inate stacked C( ± 0 )n] v w ith constan t thickness, the relative difference of the norm al buckling loads was found to decline p roportional to n 2 w hereas the corresponding value under shear decreases with n 1 only.