桥梁建设
橋樑建設
교량건설
BRIDGE CONSTRUCTION
2015年
2期
71-76
,共6页
连续刚构桥%过度下挠%组合体系%体外索%主动控制%技术措施
連續剛構橋%過度下撓%組閤體繫%體外索%主動控製%技術措施
련속강구교%과도하뇨%조합체계%체외색%주동공제%기술조시
continuous rigid-frame bridge%excessive deflection%hybrid system%external pres-tressing cable%active control%technical measure
为避免大跨连续刚构桥过度下挠及其危害，以主跨330 m的重庆石板坡长江大桥复线桥为背景，研究有效控制该类桥梁过度下挠的技术措施。该桥通过采用钢－混组合结构体系降低恒载弯曲效应；通过设置体外索主动控制梁体的下挠；通过采取合理的预应力度和布置形式优化梁体受力；并结合应用恰当的徐变理论和参数以及通过加强混凝土养护等多种技术措施综合并用。通过与该桥多年实测的下挠数据及规律的对比，验证所采用技术措施的有效性。在此基础上对大跨连续刚构桥的设计提出了选择优良的结构体系、体外索主动控制下挠、优化预应力配置、保证工期及加强养护等有效的技术措施以避免梁体发生过度下挠的建议。
為避免大跨連續剛構橋過度下撓及其危害，以主跨330 m的重慶石闆坡長江大橋複線橋為揹景，研究有效控製該類橋樑過度下撓的技術措施。該橋通過採用鋼－混組閤結構體繫降低恆載彎麯效應；通過設置體外索主動控製樑體的下撓；通過採取閤理的預應力度和佈置形式優化樑體受力；併結閤應用恰噹的徐變理論和參數以及通過加彊混凝土養護等多種技術措施綜閤併用。通過與該橋多年實測的下撓數據及規律的對比，驗證所採用技術措施的有效性。在此基礎上對大跨連續剛構橋的設計提齣瞭選擇優良的結構體繫、體外索主動控製下撓、優化預應力配置、保證工期及加彊養護等有效的技術措施以避免樑體髮生過度下撓的建議。
위피면대과련속강구교과도하뇨급기위해，이주과330 m적중경석판파장강대교복선교위배경，연구유효공제해류교량과도하뇨적기술조시。해교통과채용강－혼조합결구체계강저항재만곡효응；통과설치체외색주동공제량체적하뇨；통과채취합리적예응력도화포치형식우화량체수력；병결합응용흡당적서변이론화삼수이급통과가강혼응토양호등다충기술조시종합병용。통과여해교다년실측적하뇨수거급규률적대비，험증소채용기술조시적유효성。재차기출상대대과련속강구교적설계제출료선택우량적결구체계、체외색주동공제하뇨、우화예응력배치、보증공기급가강양호등유효적기술조시이피면량체발생과도하뇨적건의。
To avoid the excessive deflection of and its harm to the girders of long span continu‐ous rigid‐frame bridges ,the technical measures that could effectively control the excessive deflec‐tion of the girders of the bridges of the similar kind w ere researched on the Double‐Line Bridge of Shibanpo Changjiang River Bridge with a main span of 330 m in Chongqing .On the Double‐Line Bridge ,the steel and concrete hybrid structural system was used for the girder and the dead load flexural effect was thus reduced .The external prestressing cables were arranged and the deflection of the girder was actively controlled .The proper prestressing degrees and prestressing arrange‐ment were selected and the force conditions of the girder were optimized .Besides ,some more tech‐nical measures ,such as the proper concrete creep theory and parameters and the enhanced curing of the concrete ,w ere also comprehensively taken .T he contrast of the data and changing law s of the deflection of the bridge measured over years verified that all these measures worked well .Based on the research herewith ,the effective technical measures of selection of the better structural system , active control of the deflection ,using the external prestressing cables ,optimization of the pres‐tressing ,the assured construction time schedule and enhanced concrete curing were proposed for the design of the girders of long span continuous rigid‐frame bridges in order to avoid the excessive deflection .
