【作者】 金涛；

【导师】 王丹生；

【作者基本信息】 华中科技大学 ， 防灾减灾工程及防护工程， 2013， 硕士

【摘要】 土木工程结构在使用期间难免受到各种自然因素甚至是人为因素的影响而出现损伤，使用性能和安全可靠度受到影响，随着时间的推移，损伤逐渐积累，可能引起重大的安全事故。现实生活中发生了很多重大的安全事故，给人们带来了巨大的损失，因此需要对建筑结构进行实时的健康检测，对出现损伤的结构及时进行加固修复处理，而损伤识别是重要的一环。本文采用一种基于谱单元法和应变统计矩的损伤识别方法，具有很重要的现实意义。本文介绍了谱单元法的基本原理，采用谱单元法分别对简支梁和连续梁进行结构动力响应分析，并考虑了阻尼的影响，与ANSYS的计算结果进行对比，验证了谱单元法的精确性；文中介绍了统计矩的概念，给出了应变统计矩的推导过程，使之作为损伤识别指标，利用遗传算法，采用实数编码、随机遍历抽样、单点交叉、离散变异等措施，对简支梁和连续梁不同损伤工况进行了损伤识别，较好的识别出了损伤位置和损伤程度。从本文的研究中，可以得出如下结论：谱单元法求解结构动力响应，相比传统有限元法，具有划分单元少，求解精度高，计算时间短等优点；采用应变统计矩识别指标，对简支梁和连续梁的不同损伤工况很好的识别出了损伤位置和损伤程度，在无噪声情况下，识别精度很好，考虑15%的噪声影响下，识别结果误差均在工程允许误差范围内。更多还原

【Abstract】 Civil engineering structures are inevitably damaged by natural and even the influenceof human factors during the period of using. The service performance and reliability areaffected. The damage which gradually accumulated over time may lead to significantsecurity incidents. They have caused enormous personal and property losses. So it isimportant to implement the real-time detection of health for building structure. Then wecould repair and strengthen them timely. Therefore damage identification is an importantpart of reconstruction. In this paper the author presents damage identification methodbased on the spectral element method and the strain of the statistical moments, this methodmeets to need because of the important practical significance.This paper introduced the basic principles of the spectral element method. Thestructural dynamic response of simply supported beams and continuous beams wereanalyzed by this method, considering the impact of damping. The spectral element methodcould be verified by comparing with conventional finite element method. This paperintroduces the concept of statistical moments and gives strain derivation of the statisticalmoments as damage identification. Genetic algorithms, real-coded, randomly traversesampling, single-point crossover, discrete variation and other measures were used. Thedamage identification for beams at different conditions have been studied combined withthe genetic algorithm.The following conclusions can be drawn from this study: compared to theconventional finite element method, spectral element method for solving structuraldynamic response has fewer elements, high accuracy and less consuming time. The authorutilized strain identification of statistical moments as damage indicator. Combined withstatistical moments and genetic algorithm, the method could identify the locations andextent of the injury on the structures at different conditions. The recognition accuracy is also works within the error range against measurement noise and verified the effectivenessof this method.更多还原