Magneto-Elastic Sensors for Postearthquake Damage Detection in Steel Structures

用于钢结构震后损伤检测的磁弹性传感器

• 批准号: 9724948
• 负责人: ming wang
• 金额: $ 25.89万
• 依托单位: University of Illinois at Chicago
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-04-15 至 2001-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9724948&HistoricalAwards=false
• 关键词: Magneto; Elastic; Sensors; Postearthquake; Damage

9724948 Wang In this project, research is conducted toward development of a method of direct stress measurement based on the measurement of magnetization characteristics of ferro-magnetic structural materials. It has been shown that the magnetization characteristics of ferro-magnetic materials are related to the stress level, and a number of successful magneto-elastic sensors have been designed by researchers around the world. Most of these sensors are cylindrical in design and are primarily designed for measuring force and stress in cylindrical specimens. This is sometimes seen as a severe deficiency, since the bast majority of structural elements in a typical structure are planar (girders and beams, plates and decks) and the specimen under investigation cannot be enclosed within the sensor. A novel planar sensor design will be achieved using the concept of magnetic reluctance measurement for stress analysis. The sensor design philosophy emphasizes the ability to make stress measurements in the post yield region of the structure. The research consists of the following tasks: 1) design of sensors that can operate in the postyeild zone, 2) development of a residual stress sensor capable of detecting yielding, 3) development of a surface mountable planar sensor design in contrast to a cylindrical design, and 4) development of a suitable constitutive model for determination of permeability-stress relationships for sensor design and calibration. The proposed sensor is flexible and can be utilized for a variety of structural monitoring schemes, force measurement of inplanar and circular cross-sections, monitoring of prestress loss in bridge girders, and postearthquake evaluation of structural members. ***

9724948 Wang在该项目中，研究基于铁磁结构材料的磁化特性测量的直接应力测量方法的开发。 研究表明，铁磁材料的磁化特性与应力水平有关，世界各地的研究人员已经设计出许多成功的磁弹性传感器。 这些传感器中的大多数是圆柱形设计，主要用于测量圆柱形试样中的力和应力。 这有时被视为一个严重的缺陷，因为在一个典型的结构中的绝大多数结构元件是平面的（大梁和横梁，板和甲板）和被调查的样本不能被封闭在传感器内。 一种新型的平面传感器设计将实现使用磁阻测量应力分析的概念。 传感器的设计理念强调的能力，使应力测量后屈服区的结构。 该研究包括以下任务： 1)可在屈服后工作的传感器设计 区域，2）开发能够 检测屈服，3）开发表面可贴装 平面传感器设计与圆柱形设计相反， 以及4）开发合适的本构模型， 渗透率-应力关系的测定 传感器设计和校准。 所提出的传感器是灵活的，可用于各种结构监测方案，力测量inplanar和圆形横截面，监测桥梁预应力损失，和震后评估的结构构件。 ***