Application Analysis of Cast Steel Joint in 385m-high Long-span Transmission Tower

Based on 385m-high long-span transmission tower of 500kV Fengcheng to Meili project, the selection of the joint of bottom-crossarm compression member is conducted. Three types of joints are put forward and compared, including tubular joint, welded hollow spherical joint and cast steel tubular joint. 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. Due to comparison results, the cast steel joint is selected, and steel material is G20Mn5QT. Then, the nonlinear finite element analysis is performed, the force characteristics and ultimate capacity of cast steel joint is investigated, and design capacity of the joint under different load cases is calculated. It reveals that the cast steel joint is safe and reliable, and it is suggested to be wildly used in super-high transmission towers.