Effect of foundation displacement by earthquake on ultimate strength of suspension- and tension-type electric power transmission towers

2014 Fiscal Year Final Research Report

• Project/Area Number: 24560598
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Geotechnical engineering
• Research Institution: Tohoku University
• Principal Investigator: IKEDA Kiyohiro 東北大学, 工学(系)研究科(研究院), 教授 (50168126)
• Co-Investigator(Kenkyū-buntansha): YAMAKAWA Yuki 東北大学, 大学院工学研究科, 准教授 (80324010) ; TAMURA Hiroshi 東京工業大学, 理工学研究科, 助教 (10636434)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 送電鉄塔 / 耐震 / 余耐力 / 地盤変形 / 斜面 / 不同変位 / 弾塑性 / FEM解析

Outline of Final Research Achievements

In response to failure reporting of transmission towers due to support movements, in this research project, the ultimate strengths of such towers were evaluated by a series of three-dimensional nonlinear elasto-plastic finite element analyses for suspension and tension towers with several heights. Realistic external loads used in the standard design code, including tower's own weights, tension forces of transmission cables, and wind loads that vary with seasons were introduced as an equivalent nodal load in the finite element analysis. The ultimate strength of the towers under imposed support movements was estimated by a load factor of the design load. The ultimate strength tended to be reduced greatly when the support movement attained at a certain level, while such reduction of strength was quite different depending on the tower type, season load, and the direction of support movement.These results were discussed in comparison with the technical standard for support movement.

Free Research Field

鋼構造・応用力学