龙湾大桥成桥索力优化与合理施工状态研究

发布时间：2018-01-11 17:38

本文关键词：龙湾大桥成桥索力优化与合理施工状态研究　出处：《华南理工大学》2014年硕士论文　论文类型：学位论文

【摘要】：斜拉桥是一种高次超静定的复杂结构，斜拉索索力对结构体系的内力分布有很大的影响，对控制全桥受力至关重要。如何进行成桥索力优化以改善斜拉桥受力，如何通过施工达到合理成桥状态，业已成为斜拉桥设计和施工技术中最引人关注的问题之一。本文以佛山市龙湾大桥为工程背景，采用综合最小能量法、影响矩阵法以及二次规划理论的有约束最小能量法来确定其合理成桥索力。以主梁和主塔的弯曲应变能与拉压应变能之和最小为目标函数，添加指定节点位移、控制截面弯矩以及索力上下限值为约束条件，通过二次规划方法对成桥索力进行调整，利用Matlab优化工具箱进行求解，最终得到合理成桥索力。通过建立龙湾大桥施工阶段模型，根据该桥牵索挂篮特点计算施工索力，并在成桥后运用影响矩阵法对索力进行调整，使其达到合理成桥状态。本文采用单索施工，相较原双索施工方案，所需施工索力减小，且施工过程更容易实现。最后，对龙湾大桥运营阶段的静动力行为进行分析，，计算了运营阶段结构的受力与变形，并得到结构自振特性，验证了此类型斜拉桥的自振特点，同时分别探讨了结构刚度和边界条件对龙湾大桥自振频率的敏感性，得到一些有益结论。
[Abstract]:Cable-stayed bridge is a kind of complex structure with high degree of statically indeterminate. The cable-stayed cable force has a great influence on the internal force distribution of the structure system and is very important to control the whole bridge force. How to optimize the cable force of the bridge to improve the cable-stayed bridge force. How to reach a reasonable bridge state through construction has become one of the most interesting problems in the design and construction technology of cable-stayed bridges. Based on the engineering background of Longwan Bridge in Foshan City, the comprehensive minimum energy method is adopted in this paper. The constrained minimum energy method, which affects the matrix method and the quadratic programming theory, is used to determine the rational cable force of the bridge. Taking the minimum sum of the bending strain energy and the tension and compression strain energy of the main beam and tower as the objective function, the specified node displacement is added. Controlling the cross section bending moment and the upper and lower limit of cable force is the constraint condition. The cable force of the bridge is adjusted by quadratic programming method and solved by Matlab optimization toolbox. Finally, the reasonable cable force is obtained. Through the establishment of Longwan Bridge construction stage model, according to the characteristics of the bridge cable hanging basket calculation of the construction cable force, and after the completion of the bridge using the influence matrix method to adjust the cable force. This paper uses single cable construction, compared with the original two-cable construction scheme, the required construction cable force is reduced, and the construction process is easier to achieve. The static and dynamic behavior of Longwan Bridge in operation phase is analyzed, the stress and deformation of the structure in operation stage are calculated, and the natural vibration characteristics of the structure are obtained, which verifies the natural vibration characteristics of this type of cable-stayed bridge. At the same time, the sensitivity of structural stiffness and boundary conditions to the natural vibration frequency of Longwan Bridge is discussed, and some useful conclusions are obtained.
【学位授予单位】：华南理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U448.27

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