Optimization of the buckling load for composite structures taking thermal effects into account

This paper deals with optimization of the budding load for laminated compos ite structures. A new methodology has been developed where thermal residual stresses introduced in the manufacturing process are included in the buckl ing analysis. The thermal effects are also included in the calculation of t he buckling load sensitivities, and it is therefore possible to "tailor" th e thermal residual stresses in order to increase the buckling load. Rectangular plates and circular cylindrical shells subjected to axial compr ession are considered. The structures are optimized twice; the first time t he thermal residual stresses are ignored in the optimization, and the secon d time the thermal residual stresses are included in the optimization. Thes e two sets of optimizations give two important results. Firstly, it is poss ible to increase the buckling load for the structures significantly when th e thermal residual stresses are taken into account. Secondly, structures wh ich have been optimized ignoring the effects of thermal residual stresses. may have a buckling load which is much less than expected when the effects of the thermal residual stresses are included.