Some new applications of the theory of thin-walled bars

The present author has elaborated and published some papers and books concerning an original and effective complex theory for prismatic bar with any type of cross-section (CS): full, thin-walled (TW) open, closed or open-closed. There were presented some examples of the theory application and its new possibilities. The paper summarize author's observations concerning non-conventional problems analysis and synthesis of structures - specially composite ones. This time the attention is turned on following problems: analysis of simple frames applying also DMEM (Difference-Matrix Equation Method), calculation of the geometrical characteristics for bars with any CSs including typical bridge ones.