【作者】 李晓莉；

【导师】 肖汝诚；

【作者基本信息】 同济大学 ， 桥梁与隧道工程， 2007， 博士

【摘要】 本文围绕着独塔体系斜拉桥设计理论这一主线展开，对相关几方面问题进行了详细研究。 (1) 首先总结了国内外对独塔斜拉桥的研究现状，并提出了需要进一步研究的问题。对于独塔斜拉桥的研究资料并不多，所见大多集中在对传统双塔的研究上。设计理论的内涵十分丰富，包括体系、参数、特征构件、概念设计以及设计参数优化等。 (2) 从体系的概念出发，首先提出了体系的概念，然后对独塔斜拉桥体系进行系统的分类，以体系为主线，系统的研究了各种荷载作用下独塔斜拉桥各种体系的力学特性。 针对目前体系研究的现状，以实桥为研究背景，通过结构受力模型，分别研究独塔体系在活载、温度等荷载作用下的位移和内力，得到了独塔体系力学特性的系统研究结果。研究对象包括独塔普通体系、独塔协作体系和斜塔体系三个方面，普通的独塔斜拉桥又包括对称与非对称体系；协作体系的研究以独塔与连续梁、独塔与T型刚构的协作为重点；斜塔斜拉桥的研究以一座建成的无背索斜拉桥为研究对象，概括了无背索体系的受力特性。 (3) 讨论了对称、非对称形式的独塔斜拉桥主梁无索区长度变化对结构受力和刚度的影响，分析了独塔斜拉桥的梁塔刚度比变化引起结构受力变化的规律。 研究了主梁无索区长度与以下因素的关系： ①主梁与桥塔的弯曲刚度比S； ②主梁边主跨比Ls/Lm； ③拉索的刚度C，尤其是主梁主跨外边索和边跨的锚索。 (4) 研究独塔斜拉桥的特征构件端锚索。从锚索的弦向刚度、应力比影响因素、疲劳等几个方面讨论了锚索的特性，得出了一些有益的结论。 (5) 研究了独塔斜拉桥经济性能的若干指标和设计参数的优化。通过对已建独塔斜拉桥的分析，得到了包括：主边跨比、主梁高跨比、宽跨比、高宽比、索塔高跨比与主梁、桥塔、拉索经济指标的关系。在设计参数的优化中，利用优化方法中的正交试验原理对一座非对称的独塔斜拉桥方案进行了优化研究。通过16个试验模型的分析，得到了独塔斜拉桥主要参数对选定目标函数的影响曲线，从而得到最优方案。更多还原

【Abstract】 Mainlined by the design theories of single pylon cable-stayed bridges, several interrelated problems are amply studied in this dissertation as follows:(1) The existing research results and practices of single pylon cable-stayed bridges were summarized at first, and the problems, which should be studied further, are then brought forward. There are a little research on single pylon cable-stayed bridges. The traditionary research is mostly on double pylon cable-stayed bridges.The connotations of design theories is very rich, it contains research of the system of bridges, parameters, characteristic components, conceptual design and the optimization of the design parameters.(2) The conception the "system" is proposed, then basically, the system of single pylon cable-stayed bridges is classified systemically. The special mechanical behaviors of all kinds of single pylon cable-stayed systems under various loads, are systemically studied.Based on the existing research results and practices, some structure models of existing bridges, which are single pylon cable-stayed bridges, are considered, and their displacement, internal force are studied under live loads, temperature loads.etc, consequently, the systemic research results on mechanical behaviors of single pylon cable-stayed bridge systems are fined. The research objects include the bridges with common system, combined system and the system of oblique tower. The common system is studied in two sorts: symmetrical and asymmetrical; The study of the combined system emphasize on the combination between single pylon cable stayed bridge and continuous beams, and the combination between single pylon cable stayed bridge and T rigid frame; with the example of a existing single oblique pylon cable-stayed, the mechanical behaviors of such single pylon cable-stayed bridges as without backstays are summarized in the study on the system of oblique pylon.(3) In single pylon cable -stayed bridges, the length of" unsupported" deck adjacent to the end supports are the important parameters that affect the internal forces and stiffness of the structure. The influences of the above-mentioned parameters are studied both in the symmetrical system and the asymmetrical system. Besides, the stiffness ratio between girder and tower and its influences on the internal forces are described in the dissertation.更多还原