Abstract: The optimal thickness selection of reinforcement layer for section enlargement method in stone arch bridge was discussed by using optimization method. Considering the coordination deformation characteristics of reinforcement layer and the main structure , the optimal thickness of reinforcement layer was determined by optimization method. According to the method , the optimal thicknesses of reinforcement layer for different bridge span were also provided. And the function of reinforcement layer thickness and arch bridge span was estab!ished by statistical principle. This method can determine the optimal reinforcement layer thickness quickly and accurately. It is helpful for the trial and checking of section enlargement method in stone arch bridge reinforcement.

Key words: bridge strengthening, optimization method, section enlargement method

摘要： 采用优选法对增大截面加固石拱桥最优加固层厚度取值问题进行探讨。利用优选法的相关理论，考虑增大截 面加固石拱桥加固层与结构的协调变形的特点，综合评选得到一个加固层厚度最优值，并以此类推得到不同跨径的 加固层最优值，最后利用统计学原理建立加固层厚度与拱桥跨径的函数关系O 此方法能快速、准确的确定最优加固 层厚度，大大减少了采用增大截面技术加固石拱桥时所需的试算和验算的工作量。

关键词: 桥梁加固, 优选法, 增大截面法