Abstract：Geometrical parameters of 104 transmission tower bodies and 20 crossarms were statistically analyzedDistribution of the included angle β between the front face of tower segments and the vertical plane is determined between 0° and 15°Wind tunnel tests on full scale models of angle members used in transmission towers with three dimensional wind incidence angles were carried outCorresponding to the included angle β in 0°～15° with an interval of 1°，the wind incidence angle θ in the range between 0° and 180° with an interval of 5°，drag coefficients of hot rolled angle members，coldformed angle members and combined double angle members were obtainedA drag coefficient database of angle members used in transmission towers was establishedThe modification method corresponding to the included angle β was proposedThe distance ratio B/b of angle members used in transmission towers is from 7 to 70Based on the wind tunnel tests and CFD simulation analysis，effects of the distance ratio B/b on the shielding effects of leeward angle members were determinedThe relationship curves between the distance ratio B/b and the shielding factor ηm were proposed for single angle members and combined double angle members，respectivelyThe results can provide reference and basis for refine calculation of the wind loads acting on transmission towers and other highrising latticed structures.
