摘要
三主桁三索面斜拉桥是近年出现的新颖桥型,与两主桁两索面斜拉桥相比,其空间性能突出,结构内力横向分配复杂,两主桁结构的某些力学特性在该类结构中不再适用。目前国内外主要对两主桁斜拉桥和三主桁梁桥作了部分研究,而针对三主桁三索面斜拉桥的研究略显欠缺,因此有必要对三主桁三索面斜拉桥进行受力性能研究。
为了便于对称分析三主桁三索面斜拉桥的力学性能,本文所有分析结果均基于斜拉索零初拉力条件下,即通过力学推导和数值仿真模拟相结合的方法探讨了三主桁三索面斜拉桥在自重作用下的内力横向分配原理,并对该类桥型的结构特点作了阐述,具体工作如下：
(1)分析了三主桁三索面斜拉桥横向三索面索力在自重作用下的分配规律。利用MIDAS/CIVIL建立自定义有限元模型,分别分析拉索线刚度、横梁横联刚度、节点刚度等因素对三索面索力横向分配的影响；
(2)利用势能最小值原理对上述规律进行分析。首先简要介绍针对三主桁梁桥的空间分析薄壁箱梁法和两次分配法,然后利用势能最小值原理推导简化的三索杆件结构的索力表达式,并将其计算结果与有限元计算结果进行对比,阐述其横向受力原理；
(3)在已建三主桁三索面斜拉桥有限元模型的基础上,分别建立了三主桁梁桥和两主桁两索面斜拉桥模型,首先对比分析了自重作用下三主桁三索面斜拉桥与三主桁梁桥的内力横向分配的影响因素,并总结了两者在简化计算方法上的异同,然后分析了三主桁三索面斜拉桥与两主桁两索面斜拉桥在结构性能上的异同,最后总结了三主桁三索面斜拉桥的桥型特点；
(4)基于沪通长江大桥的有限元模型,计算了该桥自重作用下的主桁杆件内力与三索面索力的横向分配情况,并简要分析了沪通长江大桥在温差荷载、横风荷载和支座沉降等3种典型荷载作用下的结构内力分布情况。
The cable-stayed bridge with three-planes truss and cable is a new type of bridge appeared in recent years.Compared with the two-planes cable cable-stayed bridge,many differences do exist,such as more-obvious spatial performance and more-complicated transverse distribution,so that most of the structural behavior cannot be shared between the two bridge styles.At present, at home or abroad,researches are mainly done on the three-planes truss beam bridge and two-planes truss cable-stayed bridge,insufficiently on two-planes truss and cable cable-stayed one. So it is necessary to study deeply on the mechanical performance of the new type of bridge.
To facilitate symmetry analysis on the mechanical performance of three-planes cable-stayed bridge,all results are based on the condition of no initial tensile stay cables.That is,through the method of combination of mechanics derivation and numerical analysis,the mechanical principle of the three-planes truss cable-stayed bridge under dead weight was discussed, the structural behavior clarified as well.The work was done as follow:
(1) The distribution regularity of stay cables'tension of the three-planes truss cable-stayed bridge under dead weight was analyzed.A self-defining finite element model was established by midas/civil,which was used to analyse the factors that affect the transverse distribution of stay cables'tension, such as the stiffness of stay cables, cross beams Joints and so on.
(2) Based on the principle of minimum potential energy, relatively reasonable explanation was provided for the regularity summarized previously.The stay cable's tension expression of a simplified model of three-planes truss cable-stayed bridge's cross section was established based on the theory of principle of minimum potential energy,then compared its results with those from FEM to analyse its mechanical principle. Meanwhile, thin-wall box girder method based on spatial analysis and two-times distribution method of three-planes truss beam bridge were briefly introduced as well.
(3) Based on the previously established model by midas,models of three-planes truss beam bridge and two-planes cable cable-stayed bridge were established separately.For the first, comparative analysis of transverse distribution and simplified calculation method between beam bridge and cable-stayed one with three-planes truss was given.For the second, comparative analysis of the performance was done between two-planes and three-planes cable cable-stayed bridge.And finally, the structrural behavior of cable-stayed bridge with three-planes truss and cable was summed up systematically.
(4) Using the finite element model established by ANSYS,the situation of transverse distribution of internal forces of Hutong Yangtze river bridge trusses'bars and stay cables under self weight was clarified,and also, its internal force's distribution under three typical loads of temperature,transverse wind and support settlement were briefly analysed.
引文
[1]尹一平.大跨度三主桁高速铁路桥梁静力特性分析[D].华中科技大学,2008.
[2]高宗余.武汉天兴洲公铁两用长江大桥总体设计[J].桥梁建设,2007,01：05-09.
[3]秦顺全.武汉天兴洲公铁两用长江大桥主桥设计及关键技术研究.中国钢结构协会桥梁钢结构分会第五次学术年会论文集.
[4]秦顺全,高宗余,潘东发.武汉天兴洲公铁两用长江大桥关键技术研究[J].桥梁建设,2007,01：01-04,20.
[5]徐伟.武汉天兴洲公铁两用长江大桥主桥钢梁设计[J].桥梁建设,2008,01：04-07,22.
[6]肖海珠.京沪高速南京长江大桥主桥静力特性[D].上海：同济大学,2007.
[7]张敏.南京大胜关长江大桥受力特性、计算方法、桥面疲劳和防腐问题研究[D].湖南：中南大学,2010.
[8]京沪高速南京长江大桥正桥设计.武汉：中铁大桥勘测设计院有限公司,2005.
[9]郭子俊,肖海珠,徐伟.郑州黄河公铁两用桥主桥钢梁结构设计[J].桥梁,2010,09：58-61.
[10]范立础.桥梁工程[M].北京：人民交通出版社,2001.7.
[11]周孟波.斜拉桥手册[M].北京：人民交通出版社,2004.3.
[12]刘东芳.武汉天兴洲公铁两用长江大桥空间几何非线性有限元仿真分析[D].湖南：中南大学,2007.
[13]成井信,松下直义,山根哲雄,八田政仁.柜石岛·岩黑岛公铁两用斜拉桥的设计[J].(日本)桥梁与基础,1981.
[14]方秦汉.长江上的4座公路铁路两用桥[J].铁道科学与工程学报,2004,1(1)：10-13.
[15]林国雄,方秦汉,秦顺全,屈匡时.芜湖长江大桥设计与关键技术研究.第十三届全国桥梁学术会议论文集,1998.
[16]郭向荣,刘庆艳,曾庆元.高速铁路大跨度钢桥横向刚度限值分析[J].中国铁道科学,2001,22(05)：29-33.
[17]郭向荣,陈淮,曾庆元.铁路连续钢桁梁桥横向刚度限值分析[J].桥梁建设,2000,01：13-16.
[18]刘守龙.提高桥梁横向刚度的措施和效果[J].铁道建筑,2000,11：8-10.
[19]周智辉,曾庆元.铁路钢桥横向刚度限值分析[J].中国铁道科学,2007,28(3)：34-36.
[20]石建华,朱运河,李卫华,吴志刚.武汉天兴洲公铁两用长江大桥斜拉桥施工监控[J].世界桥梁,2010(2)：24-28.
[21]李圣慧,孟德伟.三主桁三索面公铁两用双塔斜拉桥动力特性分析[J].中国西部科 技,2010,09(09)：26-27.
[22]王俭槐.桁架空间分析的薄壁箱梁法[J].铁道标准设计,1986(003)：01-07.
[23]韩衍群.高速铁路三主桁道碴整体桥面板桁组合桥受力特性及计算理论研究[D].湖南：中南大学,2008.
[24]李的平.三主桁三索面斜拉桥索力优化及空间受力性能研究[D].中南大学,2008.
[25]罗娜,郑鹏飞.三索面三主桁斜拉桥设计参数研究[J].市政与路桥,2009,04：246-247.
[26]罗娜.三主桁三索面斜拉桥空间索力优化[D].中南大学,2009.
[27]罗许国,戴公连.三主桁斜拉桥桥而板剪力滞效应研究[J].西安建筑科技大学学报：自然科学版,2008,40(003)：297-301.
[28]刘永健,刘世忠,张俊光,邓淑飞,张国玺.三桁钢桁梁桥横桥向内力调整方法及影响参数[J].广西大学学报：自然科学版,2011,36(001)：75-82.
[29]谭明鹤,王荣辉,黄永辉.整体节点刚度对钢桁梁桥结构受力的影响分析[J].公路,2007,10：27-30.
[30]曾庆元.薄壁箱型梁计算的板桁框架法[J].铁道学报,1981,03(002)：92-104.
[31]郭金琼.箱型梁设计理论[M].北京：人民交通出版社,1991.
[32]赵经文,王宏钰.结构有限元分析[M].北京：科学出版社,2001.05.
[33]肖汝诚,项海帆.斜拉桥索力优化的影响矩阵法[J].同济大学学报：自然科学版,1998,26(3)：235-240.
[34]鲍莉霞.三主桁结构内力分配影响因素研究[J].桥梁建设,2010,04：40-42.
[35]Zhang Min, Zhang Yezhi. Structure and mechanics characteristics of two highspeed railway Yangtze bridge. Proceeding of the 12th International Conferenceon Inspection, Appraisal, Repairs and Maintenance of Structures,2010, Yantai, P.R.China,1419-1427.
[36]高宗余.中国铁路客运专线大跨度钢桥设计创新.中国高速铁路桥梁技术国际交流会论文集,2008.
[37]A.S Nowak, M.M Szerszen. Bridge load and resistance models[J]. Engineering structures, 1998,20(11):985-990.
[38]C. A Brebbia, A.J Ferrante. Computational methods for the solution of engineering proble-ms[J]. New York, Crane Russak,1978.
[39]王新敏.ANSNS工程结构数值分析[M].北京：人民交通出版社,2007.10.
[40]杨俊.基于影响矩阵的大跨度桥梁合理成桥状态与施工控制研究[D].湖北：武汉理工大学.
[41]C.C Tang, H.S Shu, Yang-Cheng Wang. Stability analysis of steel cable-stayed bridges[J]. Structural Engineering and Mechanics(South Korea),2001,11(1):35-48.
[42]K.S Kim, H.S Lee. Analysis of target configurations under dead loads for cable-supported bridges[J]. Computers & Structures,2001,79(29):2681-2692.
[43]杜正国.结构力学教程[M].成都：西南交通大学出版社,2004.8.
[44]叶梅新,张哗芝,郭向荣等.高速铁路钢桁结合梁的空间有限元分析[J].长沙：中南大学,2003.
[45]T.J.R Hughes. The finite element method:linear static and dynamic finite element analy-sis[M]. Courier Dover Publications,2012.
[46]J Cheng, J.J Jiang, R.C Xiao, H.F Xiang. Ultimate load carrying capacity of the Lu-Pu steel arch bridge under static wind loads[J]. Computers & structures,2003,81(2):61-73.
[47]吴冲.现代钢桥(上册)[M].北京：人民交通出版社,2008.6.
[48]叶梅新,韩衍群,张敏.ANSYS二次开发技术在确定斜拉桥初始恒载索力中的应用[J].铁道科学与工程学报,2005,29(002)：56-59.
[49]W Podolny, J.B Scalzi. Construction and design of cable-stayed bridges[R].1900.
[50]M.T O'BRIEN, A.J FRANCIS. Cable Movement Under Two-Dimensional Loading[J] Jo-urnal of Structural Engineering,1964,90(003):89-123.
[51]P.H Wang, T.C Tseng, C.G Yang. Initial shape of cable-stayed bridges[J]. Computers& Structures,1993,46(006):1095-1106.
[52]铁道部大桥工程局科学研究院.芜湖长江大桥关键技术研究,板桁结构受力特性试验及空间分析方法研究.2000.
[53](日)小西一郎编.朱立冬等译.钢桥[M].北京：北京人民交通出版社,1980.
[54]D Janjic, M Pircher, H Pircher. Optimization of cable tensioning in cabe-stayed bridges[J]. Computers&Structures,1997,64(14):741-758.
[55]W.X Ren. Ultimate behavior of long-span cable-stayed bridges[J]. Journal of Bridge Engineering,1999,4(001):30-37.
[56]F Baron, S.Y Lien. Analytical studies of a cable stayed girder bridge[J]. Computers&Stru-ctures,1973,3(3):443-465.
[57]R.C Tirupathi, D.B Ashok. Introduction to finite elements in engineering(third eition).N-ew York:Butterworth-Heinemann,2007.
[58]京沪高速南京长江大桥正桥设计.武汉：中铁大桥勘测设计院有限公司,2005.
[59]P.K.A Yiu, D.M Brotton. Mathematical Modeling of Cable-Stayed Bridges for Computer Analysis. Proceedings of International Conference on Cable-Stayed Bridge. Bangkok, Th-ailand,1987,261-275.
[60]郑州黄河公铁两用大桥正桥设计.武汉：中铁大桥勘测设计院有限公司,2008.
[61]高宗余.中国铁路客运专线大跨度钢桥设计创新.中国高速铁路桥梁技术国际交流 会论文集,2008.
[62]Yezhi Zhang, Yinghui Liu. Behavior of Tianxingzhou Yangtze Bridge of Wuguang passe-nger dedicated line. Proceeding of the 4th International Symposium on Lifetime Engin-eering of Civil Infrastructure(ISLEC12009),2009, Changsha, P.R.China,581-586.
