基于弹性拉索的超高墩三塔斜拉桥减震效果研究  

Study on seismic reduction effect of three-pylon cable-stayed bridge with super-high pier using elastic cables

作　　者：徐向东 盖永斌 杜镔[1] 唐志[1] 钟荣炼 XU Xiangdong;GAI Yongbin;DU Bin;TANG Zhi;ZHONG Ronglian(Guizhou Transportation Planning Survey and Design Academe Co.Ltd.,Guiyang 550081,China;School of Civil Engineering,Central South University,Changsha 410075,China;Highway Administration Bureau of Guizhou Province,Guiyang 550081,China)

机构地区：[1]贵州省交通规划勘察设计研究院股份有限公司,贵州贵阳550081 [2]中南大学土木工程学院,湖南长沙410075 [3]贵州省公路开发有限责任公司,贵州贵阳550081

出　　处：《世界地震工程》2020年第2期138-145,共8页World Earthquake Engineering

基　　金：国家自然科学基金项目(51308549);贵州省重大科技专项计划项目(黔科合重大专项字[2016]3013)。

摘　　要：为探究超高墩三塔斜拉桥在弹性拉索装置下的减震效果,首先利用SAP2000建立了考虑支座非线性和拉索几何非线性的三维有限元模型;其次基于弹性拉索装置,研究了弹性拉索刚度对三塔斜拉桥地震响应的影响;最后基于数值分析结果并结合某三塔斜拉桥实际工程提出3种减震方案。研究表明:在两边塔塔梁结合处设置弹性拉索可显著减小桥梁在地震作用下的内力和位移响应;提出的方案1(两边塔单根弹性索均为50股,单股刚度均为12000kN/m)、方案2(两边塔单根弹性索均为100股,单股刚度均为10000kN/m)和方案3(15#主塔单根弹性拉索100股,单股刚度10000kN/m;17#主塔单根弹性拉索100股,单股刚度为16000kN/m)相较于无弹性索状态,均可有效降低主塔塔底弯矩、塔底剪力、塔顶位移及主梁纵向位移;相较于方案1,方案2和方案3是更优方案。In order to explore the vibration reduction effect of the three-tower cable-stayed bridge with super-high piers under the elastic cable device, a three-dimensional finite element model considering the nonlinearity of the support and the geometrical nonlinearity of the cable is established by using SAP2000. The effect of the elastic cable stiffness on the seismic response of the three-tower cable-stayed bridge is studied. Based on the numerical analysis results and the practical engineering of a three-tower cable-stayed bridge, three vibration absorption schemes are proposed. The results show that the internal force and displacement response of the bridge under earthquake action can be significantly reduced by setting elastic cables at the tower-beam junction on side tower. Compared with the case without elastic cable, the proposed scheme I(single elastic cable adopts 50 strand and single strand stiffness is 12000 kN/m)、scheme Ⅱ(single elastic cable adopts 100 strands and single strand stiffness is 10000 kN/M) and scheme Ⅲ(single strand rigidity of the elastic cable of 15 # main tower is 10000 kN/m, single strand rigidity of the elastic cable of 17 # main tower is 16000 kN/m, and the single elastic cable adopts 100 strands) can effectively reduce the bending moment, shear force, top displacement and longitudinal displacement of the main tower. It seems that scheme Ⅱ and scheme Ⅲ are better alternatives than scheme Ⅰ.

关 键 词：桥梁工程 减震效果 非线性时程分析 高墩三塔斜拉桥 弹性拉索 

分 类 号：U448.27[建筑科学—桥梁与隧道工程]