Research on Rib Stiffener Distribution and Ultimate Strength of Steel Tubular Tower’s K-Joint

Abstract

The method of calculating K-joint’s ultimate strength given by “Code for design of steel structures” GB 50017-2003 requires that, the angle θ between K-joint’s chord and brace is no less than 30°. While, due to the request of electric gap or transmission line corridor, the angle of steel tubular tower’ K-joint in power transmission line have to be designed less than 30° sometimes. In order to solve the engineer problem, rib stiffener were usually added to K-joint structure. 3 kinds of new rib stiffener to directly-welded K-joint of steel tubular tower were designed, and numerical simulation was made to study the structures’ performance under load and ultimate bearing capacity. With new-designed rib stiffener, K-joint’s stress distribution in weld jointing area, where usually bear stress badly, is improved obviously. Stress concentration is eliminated, and maximum stress is lowered. It is suggested that, in the case of exceeding code’s suggest range, k-joint structure must be reinforced to increase intensity, and the 3 format of rib stiffeners can improve the structure’s stress distribution and ensure the security of the structure.