Key Technologies of Structure Design of 385m Super-high Long-span Transmission Tower

the project summary of the super-high steel tubular tower of 500kV Fengcheng to Meili transmission line is introduced. The dynamic characteristics analysis of the tower models with and without inner elevator shaft is conducted. The influence of elevator shaft on dynamic performance of tower model is focused on. Afterwards, the selection of leg member is performed, and concrete filled steel tube with new type of annular steel frameworks inside is selected for the leg members. Finally, the selection of the joint of compression chord of lower crossarm to main member is carried out. The cast steel joint adopts monolithic casting technology, it helps to solve the problem of space intersection of multiple members, and avoid complex welding process. The cast steel joint is selected, and the steel material is G20Mn5QT. The key technologies introduced can be wildly used in long span transmission tower.