连续梁桥挂篮结构强度校核和主桁系统有限元分析

发布时间：2019-04-25 18:44

【摘要】：挂篮悬臂浇筑法指的是在桥墩两侧设置挂篮工作平台,由桥墩平衡地逐段向跨中,对称地支模浇注混凝土梁体至设计位置,待梁体养护达到设计强度后,再拔管制孔、穿束、施加预应力的架桥方法。施工主要设备是一对能行走的挂篮,挂篮在已经张拉锚固并与墩身连成整体的梁段上移动,绑扎钢筋、立模、浇筑混凝土、施预应力都在其上进行。完成本段施工后,挂篮对称向前各移动一节段,进行下一对梁段施工,循序前行,直至悬臂梁段浇筑完成。由于具有许多优点,自上世纪60年代首次使用至今,已成为修建大、中跨径桥梁的一种有效施工手段。挂篮作为悬臂浇筑施工中的关键设备,己发展成为多种类别和定型的系列产品。研究和改进挂篮结构,不仅可以提高挂篮结构稳定性,减少施工难度,确保施工安全,还将会减小钢材使用量,缩减施工时间,获得更好的经济效益。本论文以连续梁桥施工设备挂篮为研究对象,结合某双线大桥施工具体要求,对结构设计、强度校核、主桁系统有限元仿真与试验进行研究,选题具有重要的工程应用价值。首先,分析了常用挂篮的结构特点,选择了菱形挂篮为分析对象,对主要构件进行了强度校核；其次,建立了主桁系统有限元模型,对其强度、刚度及动力学特性进行了仿真与分析,结果表明菱形挂篮结构整体是符合安全设计要求,提出了结构改进的建议；最后,建立主桁架受载情况下挠度变化量的模型,揭示了挠度变化量与安全的关联规律,通过实验,验证了规律的合理性。
[Abstract]:The hanging basket cantilever pouring method refers to the installation of a working platform for hanging baskets on both sides of the pier, from the pier to the middle of the span in a balanced way, the concrete beam body is poured symmetrically to the design position, and after the maintenance of the beam body reaches the designed strength, the control hole is pulled out and the beam is pierced, A bridge erection method by which pre-stress is applied. The main construction equipment is a pair of walking hanging baskets, which move on the beam section which has been tensioned and anchored and connected with the pier body as a whole, bind the steel bars, erect the formwork, pour concrete, and apply the prestressing force on it. After the construction of this section is completed, the basket will move symmetrically forward one section to carry on the construction of the next pair of beam segments, and proceed in sequence until the casting of the cantilever beam section is completed. Since it was first used in 1960s, it has become an effective construction method for the construction of large and middle-span bridges because of its many advantages. Hanging basket, as the key equipment in cantilever casting construction, has been developed into a variety of types and types of products. The research and improvement of the hanging basket structure can not only improve the stability of the hanging basket structure, reduce the construction difficulty, ensure the construction safety, but also reduce the amount of steel used, reduce the construction time, and obtain better economic benefits. In this paper, the continuous beam bridge construction equipment hanging basket as the object of study, combined with the specific requirements of the construction of a two-line bridge, structural design, strength check, main truss system finite element simulation and test research, the topic has important engineering application value. Firstly, the structural characteristics of the commonly used hanging baskets are analyzed, and the diamond-shaped hanging baskets are selected as the analysis object to check the strength of the main components. Secondly, the finite element model of the main truss system is established, and its strength, stiffness and dynamic characteristics are simulated and analyzed. The results show that the rhomboid hanging basket structure meets the safety design requirements and puts forward some suggestions for the improvement of the structure. Finally, the model of deflection change of main truss under load is established, and the relationship between deflection change and safety is revealed. The rationality of the law is verified by experiments.
【学位授予单位】：中南大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U441

【参考文献】