Determination of the aerodynamic coefficients of wind load for spatial trusses made of tubular profiles

This paper presents new formulas for calculating the aerodynamic drag coefficient of lattice structures, which depend on factors such as surface roughness, Reynolds number, and the geometry of the structure. A nonlinear regression method based on logarithmic transformation of the raw data is proposed for determining the shading coefficient. Comparison of the computed results with the normative values given in SP 20.13330.2016 demonstrated that the proposed formulas can be effectively used to calculate the shading coefficient for spatial trusses with tubular profiles at Reynolds numbers below 4·105, without the need to refer to the charts provided in Appendix B of the standard.