【摘要】 针对目前我国近海隔震桥梁抗震性态指标量化的研究现状,引入基于性态的抗震设计思想,利用Pushover分析方法建立量化指标限值。给出近海隔震桥梁的性态水准合理划分,选取位移延性比和支座剪应变作为量化指标,利用公式法和Pushover法计算量化指标限值。选取3条天然地震波对近海隔震桥梁进行增量动力时程分析,得到结构在不同PGA作用下的位移响应。根据不同强度地震动作用下墩顶位移和支座变形情况,与本文计算的性态指标限值进行比较分析。研究结果表明:对于低墩桥梁,公式法计算量化指标限值相较于Pushover法偏小,采用Pushover法能合理地确定性态指标,可为近海隔震低墩桥梁性态设计和易损性分析提供可行的量化分析方法。更多还原

【Abstract】 The limit value of quantitative index were given according to the performance-based seismic design idea using the method of Pushover considering the current anti-seismic performance index qualifying research of offshore isolated bridge. A classification of performance levels on the offshore isolated bridge was provided, displacement ductility ratio and shear strain of the isolated bearing were selected as the quantitative indexes, and the quantitative index limits were calculated with the formula method and Pushover method respectively. Three ground motion records under different PGA levels were chosen to calculate the displacement response of offshore isolated bridge using the method of incremental dynamic analysis. Compared with the mentioned performance index limits, the pier displacement and bearing deformation were calculated under different strengths of ground motion. The results indicate that for the low pier bridge, the Pushover method calculates reasonable performance indexes and can provide a feasible and reasonable calculation method for performance design and vulnerability analysis of offshore isolated bridge compared with the formula method by which the calculated results are smaller than the Pushover method.更多还原