【摘要】 为减小施工桥梁的地震损失,基于桥梁在施工过程中发生地震损伤和破坏的现实,以3座典型大跨悬臂施工连续梁桥为对象,在分析地震需求和抗震能力的基础上,采用能力需求比(CDR)法,研究大跨梁桥施工全过程的抗震性能和抗震安全性。研究结果表明,在悬臂施工全过程中各构件各部位的能力需求比均大于2.5,悬臂施工全过程结构抗震安全;抗震易损的部位分别位于墩底、桩顶和1号-GPZ(KZ)3SX支座;最小能力需求比集中于8号梁段、9号梁段、边跨合龙、中跨合龙和桥面施工等阶段;抗震设计应在施工的维度上,重点关注地震风险相对较大的施工阶段,确保抗震安全。更多还原

【Abstract】 Considering damage and collapse of bridges under construction conduced by earthquakes,three long span typical continuous girder bridges,under construction by the cantilever method,were studied in order to reduce the seismic losses.Based on analyses of seismic demand and seismic capacity,CDR method was used and seismic performance and seismic safety were evaluated for bridges in the whole cantilever construction process.The results show that for all positions of the components of bridges,CDRs are greater than 2.5 which means that for earthquake resistance,the structure is safe in whole construction process,and that the fragile positions are on pier bottom,pile top and No.1-GPZ(KZ)3SX bearing.The least CDRs concentrate on No.8 segment,No.9 segment,side span closure,middle span closure and the deck construction stages.In perspective of construction,the seismic design should pay more attention to those construction stages with higher seismic risk to ensure the seismic safety.更多还原