Free vibration analysis and structural optimization of stiffened panels

In this thesis, free vibration analysis and structural optimization of stiffened plates was studied. Different types of straight stiffeners were used. Examined plate types have common length, width and volume constraints. In each stiffener type, some combinations of pad elements, sub stiffener elements were used. Vibration analyses of plates were carried out using a Fortran computer code which is based on Finite Strip method and developed by Özakça[1]. Optimization of plates was carried out with same program, which uses SQP as optimization tool. By these applications the effectiveness of four plate types using straight stiffener types were investigated. Totally 168 runs were carried out for this purpose. The vibration optimization results are fluctuating in a wide range due to used elements combinations listed above and number of stiffeners. Improvements due to used element type and number of stiffeners are listed and compared according to stiffener types.