The built-up cruciform section formed by two equal-leg angles has been widely applied in extra high voltage(EHV) transmission towers, however, domestic codes provide structure requirement and overlook the influence of multi filler plates to members’ bearing capacity. For the purpose of this, a pin end experiment covering 3 different cross sections(Q420, L160*12, L160*14 and L160*16) and 7 different slendernesses(25~55) has been run. This experiment contains totally 21 specimens. Furthermore, large amounts of models have been analysis by finite element method whose parameters contain variety b/t, λ, filler plate intervals and forms, amount of bolts in filler plate. A recommended formula is given for evaluating the influence of filler plates. The results show: multi filler plates enhance bearing capacity slightly for members with λ less than 35, and the better interval for filler plates is 10i-40i(i is the minimal radius of gyration); filler plates do not work well when b/t of the member is extreme large or small, a propositional b/t range for this kind of member is 11-16; the amount of bolts in filler plate has tiny influence on members’ bearing capacity; the recommended formula is applicable and feasible for design.
Algorithm for adaptive single-phase reclosure on shunt-reactor compensated extra high voltage transmission lines considering beat frequency oscillation
