劲性骨架组合法施工的大跨径混凝土拱桥合理设计状态研究

发布时间：2018-01-28 11:39

本文关键词： 钢筋混凝土拱桥合理设计状态劲性骨架组合施工法应力控制　出处：《重庆交通大学》2014年硕士论文　论文类型：学位论文

【摘要】：近30多年来，我国建造了数量众多的大跨径混凝土拱桥，主拱圈施工方法主要是支架现浇法、缆索吊装法、劲性骨架法和转体施工法，这些施工方法在经济性和耐久性上尚存在不足。纵观国外大跨度混凝土拱桥建设，采用悬臂浇筑与劲性骨架相组合的施工方法，具有整体性好、节约钢材和对扣挂系统要求较低的优势。进入本世纪，国内采用悬臂浇筑法施工了3座钢筋混凝土拱桥，但对悬臂浇筑与劲性骨架组合施工法尚未进行过研究，因此缺乏对该工法施工的大跨径混凝土拱桥力学行为、扣索力和外包混凝土浇筑过程的了解。本文依托贵州省交通运输厅科技项目（2011-122-034）“悬浇钢筋混凝土箱型拱桥设计与施工技术研究”子课题“拱圈部分悬浇和部分劲性骨架混凝土拱圈构造与受力研究”，开展如下研究工作： ①针对300m跨试设计拱桥悬臂浇筑施工过程，结合拱圈混凝土抗弯性能低的特点，开展了“带有预测机制的应力控制前进分析”的算法研究，，以悬浇过程的拱圈混凝土上、下缘应力为控制目标，根据当前已成型节段扣索力，得到即将张拉扣索的索力可行域，利用该可行域可自动判断出扣索张拉方式（拆除已张拉扣索，整节段一次浇筑、一次张拉，分级浇筑、分次张拉）及张拉力。此外，提出了基于ANSYS的悬臂浇筑施工过程的模拟方法。 ②结合劲性骨架吊装过程受力特点，提出吊装过程扣索力计算方法，确保封铰杆件及合龙段都能以预制线形安装。同时根据无应力状态原理，提出了“大阶段”模拟中扣索索力在加密计算中的换算方法。 ③外包混凝土浇筑与悬浇节段相互影响研究。通过提取拱圈截面应力影响线，分析了外包混凝土浇筑对悬浇节段应力的影响，提出通过拆除悬浇节段扣索调整劲性骨架段线形的控制方法。本文针对悬浇与劲性骨架组合施工法提出的一整套施工阶段合理设计状态计算方法，对该工法的实践与推广具有指导意义。
[Abstract]:In the past 30 years, a large number of long-span concrete arch bridges have been built in China. The main arch ring construction methods are cast-in-situ support, cable hoisting, rigid skeleton and rotary construction. These construction methods are still insufficient in economy and durability. Overlooking the construction of long-span concrete arch bridge in foreign countries, the construction method of cantilever pouring combined with rigid skeleton has good integrity. In this century, three reinforced concrete arch bridges have been constructed by cantilever pouring method, but the combination construction method of cantilever pouring and rigid skeleton has not been studied. Therefore, the mechanical behavior of long-span concrete arch bridge constructed by this method is lacking. Understanding of the Construction process of Cable and Outsourcing concrete. This paper relies on the Science and Technology Project 2011-122-034 of Guizhou Provincial Traffic and Transportation Department). Study on Design and Construction Technology of cantilever reinforced concrete Box Arch Bridge "Subtopic" Research on the structure and Force of Arch Ring partially suspended cast and partially stiffened concrete Arch Ring ". The following studies have been carried out: 1. In view of the construction process of cantilever construction of 300m span trial design arch bridge, combined with the characteristics of low flexural performance of arch ring concrete, the algorithm of "stress control forward analysis with prediction mechanism" is studied. With the stress of the lower edge of the arch ring concrete in the process of suspended pouring as the control target, the feasible range of cable force is obtained according to the currently formed segment buckling force. By using this feasible region, we can automatically judge the tension mode of the buckle cable (removing the tensioned cable, pouring the whole segment once, one stretch, grading pouring, dividing the tension) and tensioning force. The simulation method of cantilever pouring process based on ANSYS is presented. 2 combined with the mechanical characteristics of the rigid skeleton hoisting process, the calculation method of buckle force in hoisting process is put forward to ensure that the hinged members and the closure section can be installed in the form of prefabricated lines, and at the same time, according to the principle of non-stress state. The conversion method of cable buckling force in encryption calculation in "large stage" simulation is put forward. 3Research on the interaction between the outlay concrete pouring and the cantilever section. By extracting the stress influence line of the arch ring section, the influence of the outsourced concrete pouring on the cantilever section stress is analyzed. This paper presents a control method for adjusting the linear shape of the rigid skeleton segment by removing the suspensions. In this paper, a set of reasonable design state calculation method for construction stage is put forward, which is of guiding significance to the practice and popularization of the construction method.
【学位授予单位】：重庆交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U448.22

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