搖晃橋柱應用於橋樑減震之研究

Abstract

橋樑在強震下為極易受損之結構，由於台灣地處環太平洋地震帶上，因此，橋樑的耐震能力是設計時主要的考量因素之一。傳統的耐震設計係利用材料的韌性來吸收地震輸入的能量，以避免強震時結構之崩塌。然而由最近幾次發生的強烈地震災情顯示，傳統的韌性設計並未發揮預期的耐震效果。因此，吾人亟需發展有效的橋樑耐震技術。 本文探討搖晃橋柱系統應用於高橋墩橋樑減震之可行性。由於橋墩本身具柔性，有別於純剛體之行為，因此在晃動過程中須考慮橋柱本身之撓曲。文中由能量法建立其非線性運動方程式，並藉進行廣泛的數值模擬。分析結果顯示，搖晃橋柱系統可藉由橋柱搖晃運動之機制降低結構之最大反應，大幅提升橋樑之耐震能力。因此搖晃橋柱系統在橋樑減震之應用相當可行。

In this thesis, the feasibility of using rocking pier systems (RPS) for seismic protection of bridges with slender piers is studied. Differing from rigid body, the piers are flexible and therefore the flexural behavior of the piers during rocking should be taken into consideration. In this study, the nonlinear equation of motion of RPS is derived based on an energy approach and numerical simulations are carried out extensively. Analytical results indicate that seismic responses of the bridge can be significantly reduced through the rocking mechanism provided by the RPS. The effectiveness of RPS for earthquake-resistance of bridges is confirmed.