斜拉桥塔锚固区光弹性应力分析与等倾线图像处理  

Photoelastic Stress Analysis and Image Processing of Isoclinicson the Tower Anchor-range of a Cable-stayed Bridge

作　　者：李鸿琦[1] 唐明[1] 佟景伟[1] 张东升[1] 

机构地区：[1]天津大学

出　　处：《实验力学》1996年第3期229-238,共10页Journal of Experimental Mechanics

基　　金：航空科学基金

摘　　要：本文采用光弹性冻结应力法，对独塔斜拉桥塔锚固区进行了应力分析，给出了有关截面的边界应力分布及主应力迹线，从而为优化工程设计提供了重要的参考依据。本文还提出了一种新的提取等倾线的方法──图像对数增强相减法，实现了等倾线与等差线条纹的分离，同时使条纹得到了细化，提高了处理等倾线的速度与准确度。编制了自动绘制主应力迹线的程序，利用它绘制了桥塔截面的次主应力迹线。In this paper,the experimental stress analysis on tower anchor-range of the Cablestayed Bridge has been completed with the three dimensional photoelastic frozen stress method. The boundary stress distribution and the secondary principal stress trajectories of relevant sections were obtained. The results provide the basis reference for optimizing the design of engineering.In addition,the image processing techniques of isoclinics patterns and the method of automaticallydrawing the principal stress trajectories have been studied. A new method for extracting the isoclinics,called image logarithm enhancement subtraction, was put forward and the isoclinics patterns wereseparated and narrowed by this method. The speed of the process was raised and the accuacy wasimproved. A method of drawing the principal stress trajectories using micro- computer was alsopresented. A series of programs of this process were worked out and the principal stress trajectories canbe drawn automatically.

关 键 词：斜拉桥 塔锚固区 三向光弹性 图像处理 

分 类 号：O348.1[理学—固体力学] U448.27[理学—力学]