摘要
随着拱桥跨径的逐渐增大,在拱桥理论、设计、施工、运营等方面仍有许多问题需要研究。天池特大桥是目前我国国内最大跨径的采用缆索吊装、扣挂施工技术的箱型拱桥,其单拱肋共有17个安装节段。本文以该大桥缆索吊装施工项目为依托,研究了拱肋吊装过程中拱段接头的抗弯刚度损失和扣索索力优化问题,并对吊装施工全过程的拱肋稳定性进行了分析,具有重要的理论和工程实际意义。
对于使用环氧树脂处理拱段接头的吊装施工项目,吊装落位过程对时间的要求很高。由于拱段预制时的尺寸误差及前一拱段的安装误差,使得拱段标高控制点的目标位置事先并不确定。因此,吊装时拱段的标高调整是一个动态的过程。通过研究,本文给出动态调整标高的原理和方法,并编写出计算程序。吊装时利用计算机辅助计算,有效地解决了要求实测结果快速通报的问题。
基于施工现场拱肋高程测量结果,利用神经网络方法对拱段接头的抗弯刚度进行了刚度降低识别,得出了刚度降低识别结果。采用各种不同的建模方式,分析了接头抗弯刚度损失对索力、拱肋挠度和内力的影响,明确了拱段接头的合理简化模式。在此基础上,论述了吊装施工过程中扣索索力与拱肋内力、拱轴线形的关系,讨论了结构几何非线性求解的方法与步骤。
索力优化可以确定各拱段吊装时的初始扣索索力,并且只需一次初始张拉扣索,而后不再调索,即可达到成拱线形与内力的控制目标。避免或减少了因多次张拉扣索、调整线形而引起的施工困难,加快了施工进度,消除了因多次调索而可能出现的安全隐患。基于ANSYS的APDL语言参数化编程仿真拱肋施工全过程,首先采用单步法(Single Run)法对扣索索力的初始设计进行求解,获得初始设计值;然后采用子问题法(Sub-Problem)法进行优化,求出一个最优解;再以最优解为基础,用一阶法(First-Order)法进一步优化;最后采用扫描法(sweep)扫描出扣索初始索力的最优解。
保证拱肋稳定是施工全过程和运营安全的必要条件。本文研究并确定了拱肋在吊装施工过程中的稳定性主要影响因素,从拱段接头抗弯刚度入手,针对三种拱段接头模型,计算了拱肋在拱段吊装成拱过程中的稳定系数,分析了稳定因素对不同接头模型的稳定性的影响。
There are still many questions needing researching in theory, designing, construction and operating as augmenting of the arched bridge.The main bridge of Tianchi Bridge is currently the longest span bridge of its kind in China, whose main arch rings were constructed by the precasting, lifting and erection methods and the single arch rib common 17 entries installation node . In this paper, the construction design of the cable lifting and erection for the bridge aided by stay cable suspension system is presented. It is provided with important role tedious theory of sums engineering clinical significance.
To lifting construction projects using epoxy processing the joint of arches section,hoisting technic processes needs time. In virtue of tedious dimensional error of arch segments prefabrication and arch segments tedious mounting error forward,arch segment mark height is uncertainty. So pillar hoisting elevation adjustment arch segments is dynamical procedure. This paper gives out principle and method of dynamic adjusting level and compile program. Hoisting by computer assistant calculation can solve probrem of oversee requirements measured results fast bulletin effectively.
It makes damage detection to bending rigid of arch segment joint using neureal network. Method which bases heigh survey results of arch rib under construction. It adopts kinds of different modeling mode and analysis flexural stiffness and cable tension of the joint. It discusses the connection of cable force and rib inner force of lifting construction processes, and discusses geometrical and nonlinear solving method.
Cable force optimization can confirm apiece arches section hoisting technic tense insculptate the initial cable force also merely require primary the initial tensioning. Avoiding or decreasing adjustment linear whereas arousing of construction. Based on ANSYS of APDL linguistic parameter programming simulation, the whole process of arch rib construction whole process adopts single-step method to solve original design of cable force original design and acquire the initial firstly; and adopts Sub-Problem proceed to optimize; then optimizes with First-Order based on optimal solution; eventually adopts sweep method sweeping out optimum solution of cable-stayed beginning force.
Ensuring arh rib stability is necessary condition under construction process .This text study medium of stability of main influencing factors at hoisting construction process , from arch segment joint bending rigidity, calculate stability coefficient at arch segment hoisting arching process in allusion to three species arch segment joint model, and analyze stabilization factors that different from joint models.
引文
[1]周水兴,江礼忠,曾忠.拱桥节段施工斜拉扣索索力仿真计算研究.重庆交通工程学院学报,2000,19(3):8-12[2]
[2]郑皆连,徐风云,唐柏石等.广西誉宁岂江大桥千斤顶斜拉扣挂悬拼架设钢骨拱析架施工仿真计算方法.中国公路学会桥梁和结构工程学会1996年桥梁学术论文集.北京:人民交通出版社,1996,214-228
[3]肖汝诚,项海帆.斜拉桥索力优化及其工程应用[J].计算力学学报,1998,15(1):118-126
[4]冒琴.梁拱组合桥吊杆成桥索力的确定.中外公路,2007,(3):102-103
[5]胡建华等.自锚式悬索桥恒载吊索力的设计方法研究.桥梁建设,2007,(2):39-41
[6]Fujisawa N.Tomo H.Computer-Aided Cable Adjustment of Cable Stayed Bridges[J].IABSE,1985,(4):85-88
[7]杜蓬娟,张哲等.斜拉桥合理成桥状态索力确定的优化方法[J].公路交通科技,2005,22(7):82-85
[8]张建民,肖汝诚.斜拉桥合理成桥状态确定的一阶分析方法[J].力学季刊,2004,25(2):297-303
[9]李岩等.基于Matlab优化工具箱的斜拉桥索力优化实用方法.森林工程,2006(11):35-37
[10]张建民,郑皆连,秦荣..大跨度钢管混凝土拱桥吊装过程的优化计算方法[J].桥梁建设,2002(1):52-55
[11]席红星.150m钢筋混凝土拱桥单箱悬臂吊装施工技术.铁道建筑,2002,(4):9-11
[12]李岩等.基于Matlab优化工具箱的斜拉桥索力优化实用方法.森林工程,2006,(11):35-37
[13]DinnikAN.B ucldingandTorsion.Moscow,1955
[14]Austin W J.In-Plane Bending and Buckling of Arches.ASCE,Vol.97,No.st5,May,1971:1575-1593
[15]项海帆,钱莲萍.单承重面拱桥侧向稳定的实用计算.中国土木工程学会市政工程专业委员会第一次城市桥梁学术会议论文集.1987,11
[16]钱莲萍,项海帆.空间拱桥结构侧倾稳定性的实用计算.同济大学学报,1989,17(2):161-172
[17]向中富.中承式拱桥横向屈曲临界荷载实用计算[J].重庆交通学院学报,1995,(1): 27-31
[18]李国豪.桥梁结构稳定与振动[M].北京:中国铁道出版社,1992.
[19]向中富.桥梁施工控制技术[M].人民交通出版社,2001
[20]庞大彬.大跨度钢筋混凝土箱型拱桥缆索吊装施工技术研究[J].铁道建筑技术,2003,(03):303-304
[21]毛强硕.195m钢筋混凝土箱形拱桥吊装施工技术研究[D].西南交通大学,2006
[22]陈然,卫建东.道路施工动态控制系统的设计.地矿测绘,2007,1:8-10
[23]刘圣保,王国体,丁平.白洋河大桥岩溶地质桩基工程的动态控制.工程建设,2007,5:698-700
[24](美)Satish Kumar编著.神经网络[M].北京:清华大学出版社
[25]Ghaboussi J,Joghataie A.Active control of structures using neural nefworks.J Engng Mech,ASCE,1995,(1995,12(4):555-567
[26]闻骥骏.工程结构损伤识别的反问题研究[D].武汉理工大学,2006
[27]Pandy P C,Barai S V.Multilayer perceotron in damage detection of bridge structure.Comput-ers &Structures,1995,54(4):597-608
[28]Wu X,Ghaboussi J,Garrett J H.Use of neural networks in detection of structural damage.Computers&Structures,1992,42(4):649-659
[29]飞思科技产品研发中心.神经网络理论与MATLAB7实现.北京:电子工业出版社,2005
[30]H.J.Emst.Der E—Modul von Seilen unter Beruchsichtigun des Durchanges,Der Bauingeniear.Feb.,1965,40(2)
[31]李开泰,黄艾香,黄庆怀编著.有限元方法及其应用[M].北京:科学出版社,2006
[32]Bellini P X,Chulya A.An Improved Automatic Incremental Algorithm for the Efficient Solution of Nonlinear Finite Element Equations.Computer & Structures,1987,27:625-630
[33]杜国华.斜拉桥的合理索力及其施工张拉力[J].桥梁建设,1989(3):11-17
[34]陆楸.斜拉桥最优索力的探讨[J].中国公路学报,1990(1):38-48
[35]秦顺全.斜拉桥安装计算.倒拆法和无应力状态控制法评述[A].中国土木工程学会桥梁与结构工程学会第九届年会论文集[C].上海:同济大学出版社,1992
[36]孙海涛.大跨度钢桁架拱桥关键问题研究<博士学位论文>.同济大学,2007
[37]尚晓江等.ANSYS结构有限元高级分析方法与范例应用[M].北京:中国水利水电出版社
[38]ANSYS.Inc.Theory Release5.7[S].USA,1998
[39]盛和太等.ANSYS有限元原理与工程应用实例大全[M].北京:清华大学出版社,2006
[40]ANSYS theory reference(Eighth Edition).USA,SAS IP,Inc,1997
[41]刘祖胜等.大跨拱桥悬臂浇注施工中的扣索索力优化.公路交通科技(应用技术版),2007,4:130-132
[42]ANSYS Corporation.ANSYS APDL Progragrammers Guide[Z].ANSYS Corporation,1980
[43]张建民.肖汝诚.斜拉桥合理成桥状态确定的一阶分析法.力学季刊,2004,2(25):297-303
[44]张元凯,肖汝诚.基于正装迭代法的斜拉桥合理索力优化方法.第十七届全国桥梁学术会议,2006:1050-1054
[45]曹海滨等.斜拉桥拉索无应力长度的算法研究.中南公路工程.2004,(2):45-47
[46]Kim KS Lee HS.Analysis of target configurations under dead loads for cable-supported bridges[J].Computer&.Structures,2001,79(29-30):2681-2692
[47]刘国正.优化设计及应用.人民交通出版社,1991
[48]赵雷,卜一之.大跨度拱桥施工稳定性的时变力学分析[J].铁道学报,2000,22(5):55-59
[49]李存权.结构稳定和稳定内力.北京:人民交通出版社,2000
[50]项海帆,刘光栋.拱结构稳定与振动.北京:人民交通出版社,1991
[51]NAZMYAS.Stability and load-carrying capacity of three-dimensional long-span steel arch bridges[J].ComputersandStructures,1997,65(6):857-868
[52]贺拴海.桥梁结构理论与计算方法[M].北京:人民交通出版社,2003.
[53]Bathe K L,Ramm E,Wilson E L.Finite Element Formulations for Large Deformation Dynamic Analysis.Int.J.Num.Meth.Eng.,1975,9:353-386
[54]Alexander C.Principles of Structural Stability Theory.Englewood Cliffs:Prentice-Hall,1974
[55]Shi J.Computeing Critical Points and Secondary Paths in Nonlinear Structural Stability Analysis by the Finite Element Method.Computers & Structures,1996,58:203-220
[56]段进,倪栋,王国业编著.ANSYS10.0结构分析从入门到精通[M].北京:兵器工业出版社,2006
[57]戴公连,李德建著.桥梁结构空间分析设计方法与应用[M].北京:人民交通出版社,2001