桥梁建设
橋樑建設
교량건설
BRIDGE CONSTRUCTION
2015年
4期
58-63
,共6页
匝道桥%桥墩%跨径组合%纵坡%曲率半径%地震动输入方向%有限元法%地震响应分析
匝道橋%橋墩%跨徑組閤%縱坡%麯率半徑%地震動輸入方嚮%有限元法%地震響應分析
잡도교%교돈%과경조합%종파%곡솔반경%지진동수입방향%유한원법%지진향응분석
ramp bridge%pier%span arrangement%longitudinal slope%curvature radius%ground motion input direction%finite element method%seismic response analysis
为探求匝道桥几何非规则性对结构地震响应的影响规律，基于嘉闵线匝道桥，采用SAP2000软件建立结构有限元分析模型，分析不同跨径组合、纵坡、曲率半径和地震动输入方向下的匝道桥地震响应。结果表明：与简支梁桥相比，多跨连续梁桥顺桥向固定墩、横桥向矮墩和过渡墩的响应均变大；纵坡大小对桥梁纵向地震响应影响轻微，但在横桥向设置大纵坡可减小高墩区墩柱的地震响应；小曲率半径下采用切向或法线方向输入与地震动最不利输入方向存在角度偏差，会低估结构地震响应，大曲率半径下其地震响应与直线桥基本一致，可简化为直线桥进行分析。
為探求匝道橋幾何非規則性對結構地震響應的影響規律，基于嘉閔線匝道橋，採用SAP2000軟件建立結構有限元分析模型，分析不同跨徑組閤、縱坡、麯率半徑和地震動輸入方嚮下的匝道橋地震響應。結果錶明：與簡支樑橋相比，多跨連續樑橋順橋嚮固定墩、橫橋嚮矮墩和過渡墩的響應均變大；縱坡大小對橋樑縱嚮地震響應影響輕微，但在橫橋嚮設置大縱坡可減小高墩區墩柱的地震響應；小麯率半徑下採用切嚮或法線方嚮輸入與地震動最不利輸入方嚮存在角度偏差，會低估結構地震響應，大麯率半徑下其地震響應與直線橋基本一緻，可簡化為直線橋進行分析。
위탐구잡도교궤하비규칙성대결구지진향응적영향규률，기우가민선잡도교，채용SAP2000연건건립결구유한원분석모형，분석불동과경조합、종파、곡솔반경화지진동수입방향하적잡도교지진향응。결과표명：여간지량교상비，다과련속량교순교향고정돈、횡교향왜돈화과도돈적향응균변대；종파대소대교량종향지진향응영향경미，단재횡교향설치대종파가감소고돈구돈주적지진향응；소곡솔반경하채용절향혹법선방향수입여지진동최불리수입방향존재각도편차，회저고결구지진향응，대곡솔반경하기지진향응여직선교기본일치，가간화위직선교진행분석。
To probe into the laws of influences of the geometry irregularities of ramp bridges on the seismic responses of the bridge structures ,a finite element analysis model for the structures was established ,using the software SAP2000 based on the example of a ramp bridge on the Jiamin Elevated Road Line and the seismic responses of the ramp bridges under the different span arrange‐ments ,longitudinal slopes ,curvature radii and ground motion input directions were analyzed .The results of the analysis show that as compared with the simply‐supported girder bridges ,a multi‐span continuous girder bridge can have the significant increase of the seismic responses in the fixed piers in the longitudinal direction and the low piers and transition piers in the transverse directions . T he influences of changes of the longitudinal slopes on the longitudinal seismic responses of the ramp bridges are slight ,however ,the arrangement of the heavy slopes in the transverse direction is helpful to alleviation of the seismic responses of the columns in the high pier area .Under the sharp curvature radii of the ramp bridges ,the angle deviations exist between the ground motion in‐put in the tangential and normal directions and the worst ground motion input direction ,and the seismic responses of the structures can be underestimated .Under the gentle curvature radii ,the seismic responses of the curved ramp bridges are basically consistent with the straight ones and the curved ramp bridges can be simplified as the straight ones for analysis .
