公路大跨度连续刚构桥施工控制与合龙方案研究

发布时间：2019-04-08 15:42

【摘要】：预应力混凝土连续刚构桥由于其结构受力性能好、跨越能力大等优势,近年来在高速公路中广泛运用,但与之不相适应的是:由于悬臂施工周期、合龙顺序等诸多因素,对桥梁设计的线形和内力产生较大的影响,在成桥后的使用过程中,许多大跨径连续刚构桥出现了中跨跨中变形值过大及梁体开裂的问题,这些情况给桥梁的正常使用带来了很大的问题。本文在学习和总结前人研究工作的基础上,以鱼湂大桥(99+180+99m三跨连续刚构桥)为工程背景,围绕着大跨度预应力混凝土连续刚构桥的施工控制和合龙方案进行研究。本文介绍了施工控制的基本理论,并结合工程实际情况,运用自适应理论进行施工控制,并对该桥施工过程中线形和应力实测与理论数据进行分析比对,得出梁体悬臂浇筑阶段及边、中跨合龙的线形及截面应力控制结果。对合龙误差进行了控制,在可控范围内,并预测了运营阶段收缩、徐变对梁体线形的影响和铺设二期恒载前梁体理想标高。本论文对鱼湂大桥按照先边跨后中跨、先中跨后边跨以及全桥一次合龙三种合龙施工方案进行了分析研究,运用模型计算了成桥和运营10年两个工况下主梁的线形和受力。通过对梁体竖向下挠位移和拉应力的分析比对得出较佳合龙方案,对同类桥梁的施工工序提供了一定的依据。
[Abstract]:Prestressed concrete continuous rigid frame bridge has been widely used in expressway in recent years because of its advantages of good structural performance and large span ability. However, what is not suitable to it is: due to many factors such as cantilever construction cycle, closure sequence and so on, the prestressed concrete continuous rigid frame bridge has been widely used in expressway in recent years. It has a great influence on the shape and internal force of bridge design. Many long-span continuous rigid frame bridges have some problems such as excessive mid-span deformation and beam cracking in the process of bridge completion. These conditions have brought a lot of problems to the normal use of bridges. On the basis of studying and summarizing the previous research work, this paper studies the construction control and closure scheme of the long-span prestressed concrete continuous rigid frame bridge based on the engineering background of the Yumei Bridge (99180-99m three-span continuous rigid frame bridge), which is based on the construction control and closure scheme of the long-span prestressed concrete continuous rigid frame bridge. In this paper, the basic theory of construction control is introduced, and according to the actual situation of the project, the self-adaptive theory is applied to the construction control, and the alignment and stress measured in the construction process of the bridge are analyzed and compared with the theoretical data. The linear and cross-section stress control results of beam cantilever casting stage and side and mid-span closure are obtained. The closing error is controlled in the controllable range, and the influence of shrinkage, creep on beam alignment and the ideal elevation of beam before laying the second phase dead load are predicted. In this paper, according to the construction schemes of the first side span and the middle span, the first middle span and the first middle span, and the whole bridge once closed, the alignment and force of the main beam under the two working conditions of the completed bridge and the operation for 10 years are calculated by using the model. Through the analysis and comparison of the vertical deflection displacement and tensile stress of the beam body, the better closure scheme is obtained, which provides a certain basis for the construction process of the same kind of bridges.
【学位授予单位】：兰州交通大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U445.4

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