Optimum design of stayed columns with split-up cross arm.

*(English)*Zbl 1330.74096Summary: The columns considered in this paper consist of a central mast; a split-up cross arm hinged or fixed to the central mast and optimally stressed stays. The buckling load of these columns is calculated and the influence of the geometrical parameters is examined. The indicator of volume, \(W\), is proposed as a measure of the efficiency of different structures that are designed to transmit the same load \(P\). This paper demonstrates that the stayed columns with a split-up cross arm have a number of advantages with respect to the stayed columns examined previously. It further reveals that both the sections of the stays and the cross arm length influence the buckling load and the efficiency decisively. Compared to other columns with one cross arm, an efficiency increase of more than 20% can be achieved. The efficiency is defined as the minimal volume of material needed to sustain a given load \(P\). The theory of morphological indicators is used to propose a design procedure for stayed columns. This procedure takes constraints (such as local buckling, yielding, choice of the morphology.) into consideration and proposes the most efficient column. Furthermore, it takes imperfection into account as prescribed by the construction code (Eurocode 3) [Eurocode Steel/3. Belgian Standard NBN ENV 1993-1-1: 1992/AX (1992)].

##### MSC:

74K10 | Rods (beams, columns, shafts, arches, rings, etc.) |

74P15 | Topological methods for optimization problems in solid mechanics |