Selection of Calculation Model for Steel Tubular Tower of UHV Power Transmission Line

Based on the simplified model of integral space truss,the member stress of UHV steel tubular tower is calculated by bar elements.Due to the assumption that the element only sustains axial force while the action of bending moments at its both ends are neglected,there are diffenrences between calculation results and actual conditions.Taking the steel tubular tower for 1 000 kV power transmission project from South Anhui to Shanghai,in which the double circuits on the same tower mode is adopted,as analysis object and by use of three computation models,namely the bar element model in general program for tower design,the beam-bar and beam element models in general program for finite element computation ANSYS,the static and dynamic performances of tubular tower are calculated and compared.Calculation result comparison shows that the axial force of legs and natural vibration of the tower are almost the same;the bar end bending moments respectively calculated by beam-bar hybrid element model and beam element model are similar.Thus,it is recommended that the stress of steel tubular tower for UHV power transmission project can be calculated by integral space truss method in beam-bar hybrid element model,and in the design of the steel tubular tower the effects of bending moment at member end on the stress of tower leg should be considered.