桥梁建设
橋樑建設
교량건설
BRIDGE CONSTRUCTION
2015年
2期
116-121
,共6页
斜拉桥%结合梁%几何非线性%有限元法%稳定性分析
斜拉橋%結閤樑%幾何非線性%有限元法%穩定性分析
사랍교%결합량%궤하비선성%유한원법%은정성분석
cable-stayed bridge%composite girder%geometric nonlinearity%finite element method%stability analysis
针对传统的稳定性分析方法不能反映斜拉桥施工阶段各主梁节段的稳定性的问题，基于欧拉屈曲公式和斜拉桥几何非线性稳定分析理论，提出了一种考虑几何非线性的斜拉桥主梁节段稳定性分析方法，以武汉二七长江大桥为依托，对该三塔双索面半飘浮结合梁斜拉桥施工阶段各主梁节段的稳定性进行研究。采用 MIDAS软件建立了该桥施工阶段全桥有限元模型，通过给单元施加轴力增量，反复迭代计算出主梁节段的有效长度和长细比，代入主梁节段的稳定性控制方程。结果表明：在最大双悬臂阶段时，中塔处主梁节段稳定性控制方程值为0．05～0．55，均满足规范要求，中塔支座处主梁节段是悬臂施工稳定性的关键控制部位。
針對傳統的穩定性分析方法不能反映斜拉橋施工階段各主樑節段的穩定性的問題，基于歐拉屈麯公式和斜拉橋幾何非線性穩定分析理論，提齣瞭一種攷慮幾何非線性的斜拉橋主樑節段穩定性分析方法，以武漢二七長江大橋為依託，對該三塔雙索麵半飄浮結閤樑斜拉橋施工階段各主樑節段的穩定性進行研究。採用 MIDAS軟件建立瞭該橋施工階段全橋有限元模型，通過給單元施加軸力增量，反複迭代計算齣主樑節段的有效長度和長細比，代入主樑節段的穩定性控製方程。結果錶明：在最大雙懸臂階段時，中塔處主樑節段穩定性控製方程值為0．05～0．55，均滿足規範要求，中塔支座處主樑節段是懸臂施工穩定性的關鍵控製部位。
침대전통적은정성분석방법불능반영사랍교시공계단각주량절단적은정성적문제，기우구랍굴곡공식화사랍교궤하비선성은정분석이론，제출료일충고필궤하비선성적사랍교주량절단은정성분석방법，이무한이칠장강대교위의탁，대해삼탑쌍색면반표부결합량사랍교시공계단각주량절단적은정성진행연구。채용 MIDAS연건건립료해교시공계단전교유한원모형，통과급단원시가축력증량，반복질대계산출주량절단적유효장도화장세비，대입주량절단적은정성공제방정。결과표명：재최대쌍현비계단시，중탑처주량절단은정성공제방정치위0．05～0．55，균만족규범요구，중탑지좌처주량절단시현비시공은정성적관건공제부위。
In view of the problem that the conventional stability analysis methods can not re‐flect the stability of the main girder segments of cable‐stayed bridge at construction stage and based on the Euler′s buckling formula and the geometric nonlinearity stability analysis theory of the bridge ,a kind of the stability analysis method considering the geometric nonlinearity for the main girder segments of the bridge was proposed .The Wuhan Erqi Changjiang River Bridge ,a semi‐floating system composite girder cable‐stayed bridge with three pylons and double cable planes , was cited as an example and the stability of the main girder segments of the bridge at the construc‐tion stage was studied .The software MIDAS Civil was used to create the finite element model for the w hole bridge of the bridge .By applying the axial force increment to the elements and iterative‐ly calculating ,the effective length and slender ratios of the main girder segments were obtained and were substituted in the stability control equation for the segments .The results of the study show that at the stage of the longest tw o‐side cantilever of the bridge ,the values of the stability control equation for the main girder segments nearby the intermediate pylon are 0 .05~0 .55 and can satisfy the relevant requirements in the codes .T he main girder segments nearby the bearing of the inter‐mediate pylon are the critical parts that should be controlled in the stability at the cantilever con‐struction stage .
