【作者】 孟凡强；

【导师】 周增国； 李之达；

【作者基本信息】 武汉理工大学 ， 工程力学， 2008， 硕士

【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。更多还原

【Abstract】 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.更多还原