単純鋼桁・橋脚系の鋼製ベローズを用いたエネルギー吸収型落橋防止構造の等価線形化法による設計法

抄録

This paper proposes a design method using equivalent linear method of simple steel girders and piers system with energy absorbing restrainers. The shoes of the bridge are intentionally collapsed as fuse members for heavy earthquakes, and after collapses of shoes, inertia forces and response displacements of girders are restrained by energy absorption made by steel bellows. The previous report showed the effectiveness of the proposal method by nonlinear dynamic response analysis. For multi-span simple girders, each yield strength of bellows need to be optimized and simple design methods is desired to determine ideally combination of yield strength of bellows. The proposed design methods is based on linearized modal analysis and response spectrum analysis. Nonlinear dynamic response analyses are carried out to examine the accuracy of the proposal design method.