Calculation method of stability bearing capacity of transmission tower angle steel considering semi-rigid constraint

The angle steel member is the most commonly used component form of the transmission tower structure. Considering its connection characteristics, we must deal with its stability analysis under semi-rigid constraint conditions for the proper study of the overall structure’s mechanical performance. Therefore, in order to establish a simple and high-precision method suitable for the ultimate bearing capacity analysis of the transmission tower, we build the refined finite element models of typical steel tower joints, analyze its moment-rotation curve and utilize simulation technique of spring elements to acquire the calculation method of its single angle stability bearing capacity, which is considering initial imperfection and residual stress. Furthermore, we analyze its bearing capacity under different constraint conditions such as rigid, semi-rigid and articulated connection. The results show that it is necessary to consider joint stiffness in the bearing capacity analyses. Finally, it’s confirmed that the calculation results of this method agree well with the experimental data, which validates its high accuracy. Therefore, the method provides technical support for high efficient component stability simulation in overall stability analyses of the transmission steel tower.