摘要
本文基于Croteau动冰力模型和动水附加质量建立冰水域墩柱结构地震反应简化计算模型,并进行大跨牛根拱桥分别被自由冰和固结冰包围时地震反应分析,通过对比分析拱桥主梁、拱肋内力响应及桥墩底部弯矩曲率响应,探讨自由冰和固结冰对大跨拱桥地震反应的影响。结果表明:无论是固结冰还是自由冰对牛根拱桥的自振频率影响不大,主要是由于桥墩结构刚度较大;地震作用下,自由冰和固结冰对主拱范围内的主梁和拱肋的内力影响较小,变化±3%左右,但对引桥端部和边拱端部处主梁的内力影响较大,可增大10%以上;而海冰对桥墩的地震反应的影响显著,海冰可使桥墩底部的弯矩和曲率增大数倍。因此,在进行冰水域大跨拱桥的抗震设计时,非常有必要考虑冰对桥梁结构内力的影响。
Based on Croteau ice force model and added mass method,the seismic response analysis model of a bridge pier surrounded by sea ice was put forward. Then the seismic responses of a long-span arch bridge were also studied with considering the effects of sea ice. By comparing the inner forces of bridge girder,arch rib and bridge pier,the effects of sea ice on seismic response of bridge were studied. The results show that no mater free sea ice or consolidated sea ice influences the natural frequency of the long-span arch bridge little,that mainly because the stiffness of bridge pier is too big. The sea ice influences the inner force of arch rib and bridge girder in the scope of arch rib little,and the change is about ± 3%,but influences the inner force of bridge girder at the end of bridge approach and subarch greatly,which can increase more than 10%. The sea ice can increase the curvature and flexural moment of pier bottom more than several times. So it is necessary to consider the effects of sea ice on long-span arch bridge in icy water in design.
出处
《土木工程学报》
EI
CSCD
北大核心
2013年第S1期256-261,共6页
China Civil Engineering Journal
基金
国家自然科学基金(51078033
51178045)
关键词
海冰
大跨拱桥
地震反应
动冰力模型
附加质量
sea ice
long-span arch bridge
seismic response
dynamic ice force model
added mass
