摘要
针对我国公路桥梁抗震规范中，地震作用水平相对单一且从E1地震到E2地震的重现期相差较大的现状，提出E1’地震作用水平和E2’地震作用水平，取其50年内的超越概率分别为40％和2％～3％；将桥梁结构划分为“五档”性能水平，结合4个地震作用水平，建立17个结构抗震性能目标和“四水准”的抗震设防目标；建立桥梁构件对应其力学性能的“五档”性能水平，结合“四水准”抗震设防目标，形成了C类桥梁结构对应于不同抗震设防目标的构件性能水平，完善了桥梁结构基于性能抗震设计的基本框架。在分析国内外127个以发生弯曲破坏为主的钢筋混凝土圆形截面桥墩试验研究的基础上，建立了钢筋混凝土桥墩在地震作用下处于5个性能水平的量化指标。通过与新西兰、日本和美国加州等设计规范中相关规定的比较，结果表明：该文建议的钢筋混凝土桥墩不同性能水平变形位移角限值是合理的，可用于基于性能抗震设计时桥墩墩顶位移的确定。鉴于合理性能目标确定依赖于大量试验数据积累，建议统一性能目标试验数据记录模板。
Because the consideration is quite simple in an earthquake hazard level and a marked difference inprobability of exceedance between earthquake action E1 and earthquake action E2 in guidelines for seismic design of highway bridges, a new definition of earthquake action E 1＇ with the occurrence probability of 40% in 50 years and earthquake action E2＇ with the occurrence probability of 2%-3% in 50 years is proposed, and the bridge structure performance levels categorized into five grades are established. Seventeen structure performance objectives and four seismic fortification criteria are formed. To relate bridge component to its mechanical properties at the five designated performance levels, component performance levels for different seismic fortification criterion in C bridge structures are established. It is expected that performance-based seismic design for bridge structure can be improved. Based on the statistical data of 127 seismic performance tests of RC bridge columns with circular section subjected to flexural failure, five indices for the same five designated performance levels are put forward. Comparing the drift ratio of five designated performance levels with the provisions among New Zealand standard, Japan design code, and American design code, the results show that the drift ratios for five designated performance levels is reasonable and effective. It can be used to determine displacement of pier top in the performance based seismic design. In view of performance objectives dependent on a large amount of experimental results, evaluation template for experimental results is proposed.
出处
《工程力学》
EI
CSCD
北大核心
2011年第11期96-103,137,共9页
Engineering Mechanics
基金
高等学校博士点基金项目(20100205110010)
陕西省自然科学基金项目(2010JM7002)
关键词
桥梁工程
基于性能抗震设计
抗震设防目标
性能水平
性能指标
钢筋混凝土桥墩
位移角
bridge engineering
performance-based seismic design
seismic fortification criterion
performancelevel
performance index
reinforced concrete bridge column
drift ratio
