Assessment criterion for optimum design solutions of piecewise constant sections in I-rods with stability or first eigen-frequency limits

The criterion for the minimum material consumption of strips strengthening the I-rod with stability or first eigen-frequency limits is formulated in previous studies for the case of continuous change of the variable parameter. It is known that this solution allows evaluating a real design project not only by the criterion of its proximity to the minimum material consumption, but also by the reference point in the real design. In many cases, it is used to replace the continuous change in the variable size of the rod-strengthening piecewise constant sections. The boundaries of these sections are based on the minimum material consumption. The width of the strengthening strips is determined by the optimization methods. The paper proposes the criterion allowing to correctly assess the termination of the optimization processes.

strengthening, criterion, optimization, consumption, sustainability, natural frequency, critical force, buckling, mode shapes, stresses, bending, I-rod

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