桥梁预应力体外索加固设计方法

A Design Method of Strenthening Reinforced Concrete Beam Bridge by External Prestressed Tendons

本文给出了体外预应力加固桥梁的体外索配筋设计新方法,引入了预应力度概念,同时考虑了体外索中拉力增量和预应力损失的影响。对 T 形和 I 形截面的钢筋混凝土简支梁标准图按本文方法进行了分析计算,并给出了不同荷载等级下的预应力度设计建议值。按本文方法,一旦选择了预应力度即可求出最经济的体外索配用面积,无需进行任何验算工作。

In this paper,a new design method of strengthening reinforced concrete beam bridges by external prestressed tendon is presented,taking the pres- tress degree and tension increment in the external tendon as well as the prestress loss into account.Based on the analyses of simply supported Tor I-shaped reinforced concrete beam bridge in standard drawings,the design values of the prestress degree are recommended for different loading grades on the bridges.With the method,so long as the loading grade and the prestress degree are given,the most economic sectional area of external prestressing tendons can be determined and no further check works are needed.