On the allowance for support costs in Prager-Rozvany’ optimal layout theory

A recent study by Rozvany and Sokól discussed an important topic in structural design: the allowance for support costs in the optimization process. This paper examines a frequently used kind of support —that of simple foundation with horizontal reaction by friction— that appears no covered for the Authors’ approach. A simple example is examined to illustrate the case and to apply the Authors’ method and the standard design method.

On the layout of a least weight single span structure with uniform load. Some comments and improvements

Beghini et al (Struct Multidisc Optim doi:10.1007/s00158-013-1030-6, 2013) have published a very interesting paper arriving to practically the same nearly optimal solutions for the so named “bridge prob- lem” that the Writers published a year before, but using an alternative and remarkable approach to the problem. In spite of this general agreement, the Writers think that some details of the paper can be improved and there are results that can be given a clear and mean- ingful interpretation thanks to an old and practically unknown theorem on optimal slenderness.