Static And Dynamic Response Of End Surpport On 220kV Substation Frame

Substation frame is an indispensable structure to ensure the safety of transmission line. Frames with no end support can be adopted when the frame only has a few spans. Considering larger lateral force, frames with end support is a better scheme when the frame has considerable spans. Under normal circumstance, insufficient structural stiffness is the major flaw of substation scheme, which means displacement fails to meet the requirement. Under earthquake, the substation frame may collapse successively and become instable as a whole, which results in huge economic loss and unfavorable social influence. Incorporating end support can significantly improve the stiffness and strength of the frame, consequently the static and dynamic response of the substation structure. However, related researches have rarely done so far. Thus, based on 220kV substation frame, the author has conducted some studies and proposes a few suggestions on designing and optimizing substation frame. The key points of the study are as follows:Firstly, the author studies the influence of end support on the static response of the substation frame was given at first. The results show that incorporating end support can significantly reduce the maximum moment, displacement and rotation of the miter column. Even though the influence of transverse brace on the displacement of structures is not obvious, it can reduce the maximum bending moment of the bottom of miter column by 50%. The span length has a great influence on structural displacement and rotation response.Secondly, the author given the influence of end support on the dynamic response of the substation frame. The results show that one-side brace can improve the structural stiffness by about 16 times, however, structural stiffness has little space to grow when the brace is arranged on the other side.In the end, the author researched on the seismic response of end support under frequent earthquake and rare earthquake respectively. The results show that, with no end support, structure acceleration and shear force response is at the least level while earthquake displacement reaction is great. Structure with single brace can reduce at least 80% of displacement while the acceleration response is obvious. The displacement of structure with both-side braces is 40% less than that of structure with single-side brace.