Development and Implementation of Monitoring and Damage Detection Methods for Large Civil Structures

大型土木结构监测和损伤检测方法的开发和实施，CMS提案0245402 PI：戴克，华盛顿大学本提案的重点是研究开发、验证和实施结构健康监测（SHM）策略，以检测、定位和量化大型土木结构中的结构损伤。其目标是制定适当的方法，以处理地震、风、爆炸以及老化/环境恶化等重大自然事件造成的损害。适用于大型结构（大跨度桥梁、高层建筑等）的策略由于这些结构具有紧密间隔的振动模式，因此需要特别考虑。这些结构的其他特征包括：它们是连续结构，不能用集中质量很好地表示;横向和扭转运动可以高度耦合;使用有限数量的传感器是可行的;它们具有紧密间隔的模式。传统上用于模态参数识别的方法不一定适用于具有密集模态的结构，特别是在需要算法自动化的SHM情况下。重点是SHM方法的发展，该方法使用特征值、特征向量和静态参数（斜拉桥的变形形状）的变化率来定位和量化损伤（即，敏感性）。此外，使用敏感性为基础的分析技术，SHM技术的能力和局限性，以检测各种类型的损害将检查现实的损害情况。数值和实验验证的方法计划使用现有的模型和数据从斜拉桥和悬索桥（艾默生桥跨越密西西比，在日本的白草桥）。此外，还将在Pereira-Dos Quebradas桥（1995年建造的斜拉桥）上进行全尺寸试验，该桥有一个全面运行的约300个传感器响应采集系统（传感器和数据采集）。这座桥自建造以来经历了几次地震（包括1999年的亚美尼亚地震），并有反应记录。使用这种特殊桥梁的优点包括：已经有一个完整的响应采集系统;桥梁位于地震活跃区，可以获得响应记录;世界上这个地区的温度也相当稳定（全年波动仅为20 F），表明模态参数随温度的变化预计很小（每天的变化可能主导温度效应）;大跨度桥梁的质量相对恒定;已经开发了桥梁的数字模型;该项目具有广泛的国际视角，为考虑几个国家的减灾需求提供了机会。拟议的研究与东京大学（日本，Masato Abe教授）和瓦莱大学（哥伦比亚，Peter Thomson教授）目前的研究有关，促进了三个机构之间的战略合作，并加强了个人的研究活动。已作出重大努力，鼓励这些研究人员之间的学生和教师交流，这些活动正在扩大。阿部教授拥有日本桥梁的数据，并正在进行研究，以检查现实的损害情况。他将分享以前从日本大跨度桥梁获得的数据，合作开发这些技术，并提供他在大跨度桥梁领域的专业知识。Thomson有一个合作协议和资金，以在哥伦比亚桥上实施SHM系统。他致力于用他在这一领域的经验研究温度效应，使用其他桥梁，验证现有的有限元模型，并主持一个多语种网页，供全球访问/教育（与镜像网站在华盛顿大学和东京大学）。拟议的活动将导致更好地了解大型民用结构的静态和动态特性的损害的影响，以及培训一批具有广泛国际视野的研究人员。

Development and Implementation of Monitoring and Damage DetectionMethods for Large Civil Structures, CMS proposal 0245402PI: Dyke, Washington UniversityThis proposal focuses on a research effort to develop, verify, and implement structural health monitoring (SHM) strategies to detect, locate, and quantify structural damage in large civil structures. The objective is on the development of methodologies appropriate for damage resulting from significant natural events, such as earthquakes, wind, blasts, as well as age/environmental deterioration. Strategies that are appropriate for large structures (long-span bridges, tall buildings, etc.) require special consideration due to the fact that these structures have closely-spaced vibration modes. Other characteristics of these structures include: they are continuous structures that are not well-represented with lumped masses; lateral and torsional motions can be highly coupled; using a limited number of sensors is feasible; and they have closely-spaced modes. Methods traditionally used for identification of the modal parameters are not necessarily appropriate for structures with closely-spaced modes, especially in a SHM situation where automation of the algorithms is needed. The focus is on the development of SHM methodologies that use rates of change of the eigenvalues, eigenvectors and static parameters (deformed shape, for a cable-stayed bridge) to locate and quantify damage (i.e., sensitivity-based). Additionally, using sensitivity-based analysis techniques, the capabilities and limitations of SHM techniques to detect various classes of damage will be examined for realistic damage scenarios. Numerical and experimental verification of the methodology is planned using existing models of and data obtained from cable stayed and suspension bridges (Emerson bridge spanning the Mississippi, and the Hakucho bridge in Japan). Furthermore, full-scale testing will be performed on the Pereira-Dos Quebradas bridge (a cable-stayed bridge constructed in 1995) which has a fully operational, ~300-sensor response acquisition system (sensors and data acquisition). This bridge has experienced several earthquakes since construction (including the Armenia earthquake in 1999) and response records are available. The advantages of using this particular bridge include: a full response acquisition system is already in place; the bridge is located in a seismically active area and response records are available; the temperature is also quite constant in this region of the world (fluctuating only 20F year-round) indicating variations in the modal parameters with temperature are expected to be small (daily changes will probably dominate temperature effects); the mass of long-span bridges is relatively constant; numerical models of the bridge have been already developed; and, the project has a broadly international perspective, providing an opportunity to consider hazard mitigation needs in several countries. The proposed research is linked to current research at Tokyo University (Japan, Prof. Masato Abe) and the Universidad del Valle (Colombia, Prof. Peter Thomson), facilitating a strategic collaboration between the three institutions and enhancing the research activities of the individuals. Significant efforts have been made to encourage prior student and faculty exchanges between these investigators, and these activities are being expanded. Prof. Abe has data from bridges in Japan, and is conducting research to examine realistic damage scenarios. He will share previously obtained data obtained from long-span bridges in Japan, collaborate on the development of these techniques, and offer his expertise in the area of long-span bridges. Prof. Thomson has a cooperative agreement and funding to implement a SHM system on the Colombian bridge. He has committed to examining temperature effects with his experience in this area using other bridges, verifying the existing finite element model, and hosting a multilingual web page for worldwide access/education (with mirror sites at Washington University and Tokyo University). The activities proposed will result in a better understanding of the effect of damage in the static and dynamic properties of large scale civil structures, as well as the training of a group of researchers that have a broad international perspective.