高铁大跨连续梁不同约束体系下抗震性能研究  

Study on Seismic Performance of High-speed Railway Long-span Continuous Beam Bridges with Different Constraint Systems

作　　者：周友权[1] ZHOU Youquan(China Railway First Survey and Design Institute Group Co.Ltd,Xi’an,Shannxi 710043,China)

机构地区：[1]中铁第一勘察设计院集团有限公司,西安710043

出　　处：《铁道工程学报》2024年第6期57-63,共7页Journal of Railway Engineering Society

摘　　要：研究目的:为研究不同抗震约束体系对高速铁路大跨度连续梁桥纵向抗震性能的影响,以一座跨径为(60+100+60)m的高速铁路连续梁桥为工程背景,采用OpenSees软件对全桥进行非线性时程分析,针对不同的设防烈度,从动力特性、桥墩墩底弯矩、墩顶位移、支座位移等方面,对比分析延性体系、减隔震体系以及延性体系加减隔震体系多种工况下桥梁的地震响应差别。研究结论:(1)与延性体系相比,减隔震体系可显著延长桥梁结构的自振周期;(2)对于墩高20 m的高铁大跨连续梁按罕遇地震设防时,在Ⅶ度区及以上设防烈度时,桥墩会进入延性,且位移延性系数随着桥墩配筋率的增大而减小;(3)采用延性抗震体系的高铁大跨连续梁,可通过增大配筋率和设置阻尼器减轻桥墩的损伤,使其处于轻微损伤状态;(4)采用减隔震体系可保证高烈度地震区的高铁大跨连续梁桥的桥墩在罕遇地震下处于弹性工作状态,结构的减震率可超过80%;(5)摩擦摆支座体系减震效果好,但需要通过附加阻尼的形式来满足支座设计位移需要;(6)本研究成果可为高铁大跨连续梁桥的抗震设计提供参考。Research purposes:In order to investigate the influence of different constraint systems on the seismic performance of high-speed railway long-span continuous beam bridges under longitudinal loading,a high-speed railway continuous beam bridge with span of(60+100+60)m was taken as engineering prototype.The nonlinear time-history analyses of the whole bridges were performed by OpenSees software for different fortification intensity.The seismic response of the bridge with ductility system,isolation system and attached liquid viscous damper were analyzed from the different aspects including dynamic characteristics,bottom bending moment,top displacement of columns and bearing displacement.Research conclusions:(1)The isolation system significantly increases the natural vibration period of the bridge compared with the ductility system.(2)For the high-speed railway long-span continuous beam with a pier height of 20 m,when the fortification intensity is in theⅦdegree area and above,the pier will enter the ductility,and the displacement ductility coefficient decreases with the increase of the reinforcement ratio of the pier.(3)The long-span continuous beam of high-speed railway in ductile seismic system can reduce the damage of bridge piers by increasing the reinforcement ratio and setting dampers,so that it is in a slight damage state.(4)The seismic isolation system can ensure that the piers of high-speed railway long-span continuous girder bridges in high-intensity seismic areas are in elastic working state under rare earthquakes,and the seismic reduction rate of the structure can exceed 80%.(5)The friction pendulum bearing system has good damping effect,but it needs to meet the needs of bearing design displacement through additional damping.(6)The research results can provide reference for the seismic design of high-speed railway long-span continuous beam bridge.

关 键 词：高速铁路桥梁 抗震性能 数值计算 连续梁桥 延性体系 减隔震体系 

分 类 号：U442.55[建筑科学—桥梁与隧道工程]