腹材の座屈を考慮した送電用山形鋼鉄塔架構の耐震診断手法を提案しました。電力業界では耐用年数を超えた送電鉄塔の耐震改修が急務となりつつある一方，全国25万基の既存鉄塔を直ちに改修することは現実的ではありません。そこで本研究では現行の地震荷重を受けたときに倒壊する鉄塔をスクリーニングし，耐震改修の優先順位付けするための耐震診断手法を提案しました。管轄する法規が違うだけで、これほど常識が違うものかと大変勉強になりました。論文はこちら
The structural requirement of truss tower for power transmission is generally determined by wind load, and consideration of seismic loads may be omitted. However, in recent years, large seismic ground motions are assumed, and it is required to grasp the margin of seismic performance of existing towers. On the other hand, in Japan, there is an urgent need to reinforce and rebuild steel towers whose strength will be insufficient due to the increase in expected external load, including the rebuilding of steel towers that will exceed their useful life. However, it is practically difficult to reinforce or rebuild all existing towers immediately. Therefore, it is necessary to screen the structural safety of existing towers reasonably and easily from various points of view and prioritize various measures, and the construction of screening methods focusing on seismic performance is required as one of the indicators. In this paper, simple seismic damage evaluation of the steel tower for power transmission considering global buckling of braces is proposed, which can be used as an index for seismic performance screening focusing on the large seismic ground motion of the existing towers.