rational design

The article examines the issue of the occurrence and influence of bending moments on the bearing capacity of a combined steel truss made of rectangular bent-welded profiles. A comparative analysis of technical and economic indicators in terms of material intensity, labor intensity, and cost of traditional-typical and lightweight combined steel trusses was carried out. The paper examines steel trusses of long-span buildings with a span of 30 m. The force graphs (bending moments and axial forces) for various calculation schemes of the combined steel truss are shown.

In this article, a comparative assessment of the technical and economic efficiency of rational combined steel trusses with typical trusses according to DSTU is considered. New rational constructive combined forms of covering systems (roof trusses) have been developed for spans of 18, 24 and 30 m, with less material consumption and labor intensity compared to existing analogues.

In this article, a new method of increasing the efficiency of combined steel roof trusses is proposed and considered. A rational shape of the steel roof truss, including its topology and rational geometric parameters, was obtained, but without obtaining a rational SSS. A proposed method provides the adjustment of SSS in the truss by changing the upper belt panel length. On the basis of the obtained rational SSS of the combined truss, a new structural form is proposed.

In this article on increasing the efficiency of steel combined structures, the tasks of rational design, regulation and control of structural parameters of elements, the use of steels with increased mechanical properties are considered. It is shown that for a six-span stiffening girder of a combined truss with elastic supports, which operates under a distributed load, the moment is 72 times smaller than the moment of a single-span beam. It is suggested to use high-strength steel for truss braces. Rationality criteria are proposed.

In this article, the rational constructive form of the combined steel truss with a span of 30 meters is received, with 59% fewer elements than the typical. Calculated regulation methods are offered stress-deformation state (SDS) combined steel trusses, which make it possible to increase their efficiency. Methods of estimated SDS regulation in combined steel trusses are given: change in the stiffness of the rodsand the creation of eccentricities in the nodes connecting the lattice to the upper belt and supporting eccentricities.