【作者】 曹水东；

【导师】 李传习； 徐飞鸿；

【作者基本信息】 长沙理工大学 ， 桥梁与隧道工程， 2006， 硕士

【摘要】 本文利用模态分析的方法，通过模态参数构造损伤识别指标，进行了桥梁结构的损伤识别研究。首先利用基于结构柔度矩阵的柔度曲率比识别结构的损伤位置。然后使用双向自适应变步长变异遗传算法进一步识别出损伤的程度。全文共分四章，主要完成了以下一些工作： 1) 阐述了桥梁结构损伤识别的意义、内容和方法，介绍了现阶段国内外在损伤识别领域的研究现状和所取得的研究成果。 2) 提出了基于结构柔度矩阵的柔度曲率比识别结构的损伤位置的方法，推导了柔度曲率比的求解公式，并利用该方法进行了简支梁、连续梁和悬臂梁的损伤位置的数值仿真识别。 3) 系统介绍了遗传算法的基本理论，改进了自适应遗传算法，提出了双向自适应变步长变异遗传算法。 4) 使用Matlab语言编写了基于双向自适应变步长变异遗传算法进行桥梁结构损伤大小识别的应用程序，并在简支梁的损伤大小识别的仿真计算实例中取得了很好的识别效果。 5) 结合拱肋工程实例，利用本文的研究成果和自编应用程序进行了拱肋结构的初始损伤状态的损伤识别，取得了与静载试验比较吻合的识别结果。 6) 数值仿真分析和现场测试结果证明，本文研究取得的损伤识别的理论与方法用于桥梁结构的损伤识别是合理、可行的。更多还原

【Abstract】 In the article a new identification index based on mode parameters is used to detect bridge structures’ damage, first of all the damage positions are identificated by the method named by flexibility curvature rate method based on structure flexibility matrix. Whereafter, damage degree is calculated out by the method named bidirectional variable step adaptive genetic-algorithms, the article is made up of four chapters. The main contents and contributions of the research are summarized her.1) It claborates the significance,contents and technique of the damage identification in the field of bridge construres. Some research status quo and acquired achievements in the field home and overseas are introduced.2) In the article, a new method named by flexibility curvature rate method based on structure flexibility matrix is presented. Some correlative foemulas are deducted. The methold is used to identificate the damage positions of simple- supporting beam, continuum beam and cantilever beam by numerical simulations .3) The genetic-algorithms theory is introduced systemically. The adaptive genetic-algorithms is improved and a methold named bidirectional variable step adaptive genetic-algorithms is brought forward.4) An damage identification program based on bidirectional variable step adaptive genetic-algorithms is programmed with Matlab computer larguage and is used to identificate a simple- supporting beam’s damage degree by numerical simulations. A perfect result is acquired.5) Based on the project example of arch, the research achievements and damage identification program are used to identify arch’s initial damages. An result accord with the one from static load experimentation is gotten.6) the numerical simulation results and locale test result indicate that the theory and method offered in the article are reasonable and feasible to be used to identificate bridges structures’ damages.更多还原