【摘要】 对比1994年美国北岭地震、1995年日本阪神地震和2008年中国汶川地震中桥梁震害特点,分析了中国与国外桥梁结构在传力体系方面的差异,并对美国、日本与中国抗震规范中支座验算规定进行了比较,指出目前中国公路桥梁抗震设计规范在借鉴国外规范时存在的一些问题,给出以下改进建议:①中小跨径桥梁抗震设计时应利用桥梁上部结构在支座上发生摩擦滑移消耗地震能量,减小传递到下部结构的地震力;②抗震规范中板式橡胶支座的变形或抗滑稳定性不作为抗震验算是否满足要求的依据,应重视支座对桥梁整体性能的影响,综合考虑支座剪切变形、损坏以及防落梁装置的力学行为;③针对各国桥梁抗震设计规范中材料强度指标的差异,给出了中国常用混凝土抗压强度与美国规范混凝土抗压强度的换算公式;④《中国地震动参数区划图》(GB 18306—2001)中只提供了重现期475年的地震动参数,对应其他重现期采用不同重要性系数予以调整,而美国提供了重现期475,975,2 475年的地震动参数,建议直接采用地震动参数来描述地震危险性;⑤不同水准地震作用下,对桥梁结构不同部位、不同构件制定不同的设计目标,明确具体构件的强度、延性参数指标等;⑥桥梁抗震构造措施应按桥梁重要性及地震危险性划分,不应按照烈度划分。更多还原

【Abstract】 Compared the bridge damage characteristics in 1994 Northridge Earthquake in America,1995 Kobe Earthquake in Japan,and 2008 Wenchuan Earthquake in China,the differences of transmitting path of bridge structure between China and abroad were analyzed.Meanwhile,the bearing checking regulations in Chinese seismic specifications were compared with those in American and Japanese specifications.The problems in current Chinese seismic specifications were put forward when referring to foreign bridge specifications,and the suggestions were proposed as followings: ①The friction slipping mechanism of superstructure movement on bearings should be used to dissipate seismic energy,which reduced the seismic force transmitting to substructures;②It should not be taken as guide that the bearing met the requirements of deformation and anti-sliding stability in earthquake,and the suggestions that paying attention to the bearing performance,and considering the influences of bearing shear deformation,bearing damage,and unseating prevention system were proposed;③Aimed at the difference of material strength index between Chinese and foreign bridge seismic design specifications,the relation equation of concrete compressive strength was given,which was commonly used in Chinese and American specifications;④Only the earthquake ground motion parameters of moderate earthquake level of 475 years return period were provided by Seismic Ground Motion Parameter Zonation Map of China(GB 18306—2001) while in American specifications,the earthquake ground motion parameters of three different return periods of 475,975,2 475 years were provided,the seismic hazard should be described by earthquake ground motion parameters;⑤Different design aims should be laid down according to different parts of the structure and components,especially in the seismic design of bridges,strength and ductility of concrete components parameters should be explicated under different level earthquakes;⑥Bridge seismic construction measures should be divided by importance of bridge and seismic hazard,not intensity.更多还原