Design Optimisation of a Truss-to-Column Connection in a Frame Structure Made of Round Tubes

Introduction. The article investigates the ways to optimise the design of a truss-to-column connection in a frame structure made of round tubes. A steel lattice frame with a span of 66 m has been studied. A spanning member of a frame in the form of a truss transmits loads to a frame column through a rigid truss-to-column connection. In such structures, the maximum bending moments are applied to a truss-to-column connection, thus the problem of regulating its geometry is one of the objectives to be solved within the optimal designing. The aim of this paper is to create the most rational design solution for such a connection.Materials and Methods. In the lattice frames, depending on the chosen design, 5 to 7 members subject to compression stress converge at its inner side. The conventional variants of executing this connection would require using the heavy wall tubes which would result in the excess of material consumption. Within the research, modeling and calculation of various configurations of the truss-to-column connection were executed. The analysis of the calculation results revealed the shortcomings of the studied truss-to-column connection in a frame structure.Results. As a result of the connection design optimisation, a new configuration was suggested, where the connection of a bottom chord was executed by a slotted gusset plate. Such a solution allows for the most complete use of the bearing capacity of the bottom chord cross section.Discussion and Conclusion. As a result of the optimisation, the proposed design of a truss-to-column connection makes it possible to reduce the metal consumption while maintaining the relative simplicity of manufacture. At the same time, by reducing the local stresses, it is possible to achieve the greater strength and reliability of a truss-to-column connection.