大跨度斜拉桥近断层地震响应及减震效果分析  

Analysis of seismic response and its reduction effect of long-span cable stayed bridge under near-fault earthquakes

作　　者：李永斌[1] 

机构地区：[1]中交第二公路勘察设计研究院有限公司,湖北武汉430056

出　　处：《世界地震工程》2017年第2期241-246,共6页World Earthquake Engineering

摘　　要：历次震害表明,近断层地震对大量土木工程结构造成了灾难性的破坏。为了研究大跨度斜拉桥的近断层地震响应规律及其减震装置的减震效果,选取3条典型近断层地震波作为地震输入,利用MIDAS CIVIL软件对大跨度斜拉桥的近断层地震响应进行了分析,并对其减震效果进行了探讨。结果表明:大跨度斜拉桥的近断层地震响应随着PGV/PGA值的增大而大幅度增大,其中速度脉冲效应的影响非常显著;减震措施对纵向近断层地震作用下的减震效果要好于横向地震作用下的效果,且PGV/PGA值越大,减震效果越小。在近断层地震作用下,斜拉桥在考虑减震措施后仍具有较大的梁端位移,需引起足够的重视。All previous earthquake damage shows that the near-fault earthquake causes a disastrous damage to a large num- ber of civil engineering structures. In order to study the seismic response law of long-span cable stayed bridge and the vibra- tion reduction effect of damping device, three typical near-fault earthquake waves were selected as seismic inputs. The near- fault seismic response of long-span cable stayed bridge was analyzed by using CML MIDAS software, and the seismic re- duction effect was discussed. The results show that the seismic response of long-span cable stayed bridge increases greatly with increase of PGV/PGA value, and the influence of velocity pulse effect is very significant. The irnquence of vibration reduction measures on the longitude earthquake is better than that of transverse earthquake, and the larger the PGV/PGA value, the smaller the vibration reduction effect. Under the near-fault earthquake, the cable stayed bridge has a large longitudinal displacement of the beam end after considering the vibration reduction measures, which needs to cause enough attention.

关 键 词：大跨度斜拉桥 近断层地震 PGV/PGA值 地震响应 减震效果 

分 类 号：U448.25[建筑科学—桥梁与隧道工程]