【作者】 张艳；

【导师】 钱永久；

【作者基本信息】 西南交通大学 ， 桥梁与隧道工程， 2008， 硕士

【摘要】 体外预应力技术作为后张预应力体系的重要分支之一,可应用于各类新建、重建、改造、加固工程,是一种积极的主动加固方式。采用体外预应力技术对结构进行加固和改造,能够有效提高构件的抗弯和抗剪能力。目前,体外预应力加固技术在国内外的应用十分广泛。因此,对该技术的研究具有重要的理论价值及实用价值。本文对体外预应力加固技术进行了比较系统的研究。在充分掌握国内外相关试验资料、研究文献、设计规范的基础上,深入学习了体外预应力加固法的基本理论及设计方法。在此基础上,结合工程实例探讨了大跨预应力混凝土连续刚构桥的病害分析方法,并对相应的体外预应力加固设计方法和步骤进行了阐述。本论文主要完成了以下方面工作:(1)论述了体外预应力技术的国内外发展与研究现状,阐明了进行桥梁加固新方法研究工作的必要性。(2)本文对体外预应力加固机理进行了详细探讨,并对体外预应力结构的关键问题:应力增量计算、动力问题和预应力损失计算等进行了研究。(3)介绍了体外预应力加固体系的构造、防腐、防护以及减振等问题,总结了目前常用的体外预应力布筋方式。(4)结合工程实例,对体外预应力技术在连续刚构桥加固中的应用进行研究,具体介绍了体外预应力加固设计方法。其研究成果可为同类工程的实施提供参考。更多还原

【Abstract】 As an important branch of post-tensioned prestressing system, external prestressing technique can be employed for building, rebuilding, rehabilitation and strengthening project. External prestressing technique which is a kind of active strengthening method, can improve the component’s capacity of bending resistance and shear resistance.Strengthening techniques of external prestressing are studied systematically in this thesis. On the basis of analyzing domestic and abroad related literatures and design specification, the fundamental theory and design method of external prestressing strengthening system are taken as main subjects invesitgated. Combining engineering case study, the reason of damaged concrete continuous beam and the corresponding design method and process of strengthening with external prestressing are disscussed. The following aspects are included in the thesis:(1) The current state and the development trend of the external prestressing technique are expounded, and the necessary and urgency of bridges strengthening illuminated.(2) The theory of bridge strengthening with external prestressing is demonstrated in detail, the key problems of external prestressing structure such as the stress increment, dynamical problem and stress loss etc are studied.(3) The formation, preservation, antivibration of external prestressing system are introduced, and commonly bar arranging way of external prestressing are summarized.(4) Combining theory with engineering practice, the design and calculation of the continuous rigid-framed bridge strengthening by external prestressing bridge are studied. The research findings can offer a reference for similar engineering.更多还原