Synthesis of rational topology of combined steel trusses

The paper proposes a rational new constructive form - a combined low-element truss with a span of 30 m. Theoretical bases of rational constructive topology of combined steel trusses are given. It is shown that the new idea of the constructive decision of a steel structure can give bigger effect, than its optimization on physical and geometrical parameters. According to the results of research, it is established that it is more rational to use statically indeterminate combined steel trusses with an inseparable upper belt. According to the results of research it is established that the most rational is the topology of combined trusses with the ratio of the mass of the stiffening beam of the combined truss to the total mass of the truss equal to 50%, which provides a minimum weight of the truss. The evaluation of rational parameters of combined steel trusses by the method of mathematical planning of the experiment is carried out. It is obtained that the ratio of the mass of the stiffening beam of the combined truss to the total weight of the truss equal to 50% is rational for different heights and different values of the spans of the combined steel trusses.