世界桥梁
世界橋樑
세계교량
WORLD BRIDGE
2015年
1期
65-69
,共5页
连续梁%组合箱梁%宽桥面%横隔梁%波形钢腹板%正应力%剪力滞%有限元法
連續樑%組閤箱樑%寬橋麵%橫隔樑%波形鋼腹闆%正應力%剪力滯%有限元法
련속량%조합상량%관교면%횡격량%파형강복판%정응력%전력체%유한원법
continuous girder%composite box girder%wide bridge deck%diaphragm%corruga-ted steel web%normal stress%shear lag%finite element method
目前关于横隔梁对波形钢腹板PC连续梁桥纵向正应力的影响，都是基于小梁试验或理论分析的基础，与实际有差别。鉴于此，依托一在建单箱九室波形钢腹板PC组合连续箱梁桥，建立该桥有限元模型，分析3车道偏载作用下有无横隔梁2个工况下箱梁顶、底板的纵向正应力分布规律和剪力滞效应。结果表明：未设横隔梁的桥梁纵向正应力分布变化剧烈，距墩顶越近，顶、底板正应力横向分布变化越大；设置横隔梁后桥梁纵向正应力分布较为均匀，顶、底板正应力横向分布在跨中截面附近变化较大；未设横隔梁与设置横隔梁时顶、底板正应力最大比值分别为1．47、1．32；设置横隔梁的桥梁在汽车荷载下剪力滞效应最大，3车道偏载与6车道对称荷载作用下箱梁顶板剪力滞系数比值为1．04，底板剪力滞系数比值为1．06；横隔梁对改善箱梁正应力分布、降低剪力滞程度具有显著影响。
目前關于橫隔樑對波形鋼腹闆PC連續樑橋縱嚮正應力的影響，都是基于小樑試驗或理論分析的基礎，與實際有差彆。鑒于此，依託一在建單箱九室波形鋼腹闆PC組閤連續箱樑橋，建立該橋有限元模型，分析3車道偏載作用下有無橫隔樑2箇工況下箱樑頂、底闆的縱嚮正應力分佈規律和剪力滯效應。結果錶明：未設橫隔樑的橋樑縱嚮正應力分佈變化劇烈，距墩頂越近，頂、底闆正應力橫嚮分佈變化越大；設置橫隔樑後橋樑縱嚮正應力分佈較為均勻，頂、底闆正應力橫嚮分佈在跨中截麵附近變化較大；未設橫隔樑與設置橫隔樑時頂、底闆正應力最大比值分彆為1．47、1．32；設置橫隔樑的橋樑在汽車荷載下剪力滯效應最大，3車道偏載與6車道對稱荷載作用下箱樑頂闆剪力滯繫數比值為1．04，底闆剪力滯繫數比值為1．06；橫隔樑對改善箱樑正應力分佈、降低剪力滯程度具有顯著影響。
목전관우횡격량대파형강복판PC련속량교종향정응력적영향，도시기우소량시험혹이론분석적기출，여실제유차별。감우차，의탁일재건단상구실파형강복판PC조합련속상량교，건립해교유한원모형，분석3차도편재작용하유무횡격량2개공황하상량정、저판적종향정응력분포규률화전력체효응。결과표명：미설횡격량적교량종향정응력분포변화극렬，거돈정월근，정、저판정응력횡향분포변화월대；설치횡격량후교량종향정응력분포교위균균，정、저판정응력횡향분포재과중절면부근변화교대；미설횡격량여설치횡격량시정、저판정응력최대비치분별위1．47、1．32；설치횡격량적교량재기차하재하전력체효응최대，3차도편재여6차도대칭하재작용하상량정판전력체계수비치위1．04，저판전력체계수비치위1．06；횡격량대개선상량정응력분포、강저전력체정도구유현저영향。
Currently ,the influence of diaphragms on longitudinal normal stress of PC continu‐ous girder bridge with corrugated steel webs is examined on the basis of small beam tests and theo‐retical analysis ,which is possibly different from the actual condition .For this reason ,a nine‐cell single box PC composite continuous girder bridge under construction was taken as the study back‐ground .The finite element models of the bridge ,with and without diaphragms respectively ,were established to analyze the distribution law of longitudinal normal stress and shear lag effect in the top and bottom slabs under the action of 3 lanes of eccentric loads .The results of the study indi‐cate under the condition that no diaphragms are installed ,the longitudinal normal stress distribu‐tion show s violent variation ,the transverse distribution of normal stress in the top and base slabs exhibits greater variation as closer to the pier top .But w hen diaphragms are installed ,the longitu‐dinal normal stress distributes more uniformly ,substantial transverse distribution variation of the normal stress in the top and base slabs was found near the midspan cross section .The maximum ratio of the normal stress in the top and bottom slabs when the diaphragms are not installed is 1 .47 ,and 1 .32 when the diaphragms are installed .The bridge with diaphragms generates maxi‐mum shear lag effect under traffic loads .T he shear lag coefficient ratio of top slab shears under the action of 3 lanes of eccentric loads and 6 lanes of symmetrical loads is 1 .04 ,w hereas that of the base slab is 1 .06 .Diaphragms have significant effects on the improvement of the box girder normal stress distribution and the reduction of shear lag effect .
