体外预应力技术在桥梁工程中的应用要点解析

Analysis on the Application of External Prestressing Technology in Bridge Engineering

探讨了在体外预应力桥梁设计中引入防火性能设计的必要性,提出了防火性能的影响因素及设计原则;介绍了体外预应力钢束应力增量及二次效应的概念,对不同规范中有关钢束应力增量的规定及关于定位块的构造规定进行了横向对比;通过梳理体外预应力的构造体系,重点分析了钢束锚固区的受力特点及其设计方法,以期为同类结构的设计工作提供参考。

The necessity of introducing fire performance design into the design of external prestressed bridges was discussed,and the influencing factors and design principles of fire performance were proposed.The concepts of stress increase and secondary effect of external prestressed tendons were introduced.The provisions about the stress increment of prestressing tendons and the structural provisions about the positioning block in different codes are compared laterally.By combing the structural system of external prestressing,the stress characteristics and design methods of the anchorage area of prestressing tendon are analyzed in detail,with a view to providing a reference for the design work of similar structures.