大跨度连续梁桥减隔震设计研究

大跨度连续梁桥固定盆式支座在强震作用下往往会发生剪切破坏,如采用加强固定盆式支座的方法来强行保证其安全,将会使固定墩承受较大的地震力和塑性变形。针对这一现象,本文对大跨度连续梁桥的减隔震设计进行了探讨,提出将固定盆式支座改为活动盆式支座,并采用弹塑性减震耗能装置与其并联使用。文中结合一个工程实例,对这种方法的减震效果进行了分析。分析结果表明,在固定墩上采用活动盆式支座与弹塑性减震耗能装置并联,能够有效地减小固定墩所受的地震力,改善结构的抗震性能。

Research on seismic isolation design for long-span continuous bridges

Fixed-pot bearing supports for long-span continuous bridges are often damaged in shear under strong earthquakes.However,if the fixed pot bearing is reinforced to ensure its safety,the bridge pier will suffer larger seismic load,thus results in plastic deformations.In this paper,the design on the use of seismic isolators for long-span continuous bridges is discussed,and a system of a sliding pot bearing combined with an elasto-plastic device in parallel is proposed to substitute the fixed pot bearing on the pier.The effectiveness of the proposed isolation system is illustrated by a bridge project.The test results show that the proposed system can indeed improve the seismic performance of the bridge,thus reduces the seismic load on the pier.