Nondestructive Evaluation of FRP-Confined Concrete Using Microwave

玻璃钢约束混凝土的微波无损评价

• 批准号: 0324607
• 负责人: Oral Buyukozturk
• 金额: --
• 依托单位: Massachusetts Institute of Technology
• 依托单位国家: 美国
• 项目类别: Continuing grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-11-15 至 2008-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0324607&HistoricalAwards=false
• 关键词: Nondestructive; Evaluation; FRP; Confined; Concrete

Nondestructive Evaluation of FRP-Confined Concrete Using Microwave, CMS project 0324607PI: Oral Buyukozturk, MITFiber-reinforced plastic (FRP) composite jacketing systems have emerged as an alternative to traditionalconstruction, strengthening, and repair of reinforced concrete columns and bridge piers. A large numberof projects, both public and private, have gone after such technology and escalating deployment has beenexpected, especially in seismically active regions. Yet, an efficient and effective structural evaluationtechnology that is capable of assessing the concrete conditions inside the FRP jacketing systems islacking. It is clear that a reliable concrete imaging technology needs to be soon developed to catch upwith the surging industrial applications.The objective of this research is to develop and apply effective nondestructive evaluation (NDE) imagingtechniques to visualize and quantify damages such as FRP delaminations and concrete cracking andcrumbling in FRP-confined reinforced concrete members using wideband radar. To achieve the objective,theoretical models and design of image reconstruction algorithms will be developed for automaticprocessing of measured data in parallel with experimental studies of physical models both in laboratoryand field settings. A database of electromagnetic (EM) properties of various FRP, concrete, and FRP-concrete hybrid media will also be established to facilitate these developments. The research plan consistsof four major tasks: (a) Numerical modeling of wave propagation and scattering, (b) Determination ofdielectric properties of FRP, concrete, and FRP-concrete hybrid media, (c) Physical radar measurement,and (d) Signal processing and image reconstruction. The four tasks are closely knitted in nature and willbe conducted in an iterative and evolutionary fashion.For this proposed work, a novel data focusing methodology using wideband radar is proposed for aneffective detection of various damage mechanisms associated with the FRP bonded and confinedreinforced concrete systems. Owing to the novelty of using wideband radar to detect damages of FRPconfined concrete, a one-year exploratory study has been underway since September 2002 under the NSF Small Grant Exploratory Research (SGER) program to initially demonstrate the potential capability of the herein proposed methodology. From this exploratory work thus far, promising results have been obtained. With this present proposal, funding is sought to fully develop the methodology and perform acomprehensive theoretical/experimental research toward achieving the objectives as stated above.Considering its non-traditional civil engineering nature, this project will synthesize the knowledge andunderstanding that has been developed in the areas of structural engineering, material science, electricalengineering and computer science. This multidisciplinary research project will be performed withcollaboration of Department of Civil and Environmental Engineering, Department of ElectricalEngineering and Computer Science, Research Laboratory of Electronics, and Lincoln Laboratory of theMassachusetts Institute of Technology.It is envisioned that the proposed work will significantly advance scientific knowledge in the areas of computer simulation, innovative imaging concepts, signal processing and image reconstruction, and laboratory methodologies dealing with radar measurements. Development of knowledge as a basis for manufacturing an effective equipment in this field will directly impact the profession, and benefit engineers, transportation infrastructure communities, and decision-making authorities worldwide. Application of the knowledge and technology developed will help ensure public safety against unanticipated failures of structural systems repaired or renewed using FRP composites. Developed knowledge and methodologies will be integrated into education via course curriculums and professional workshops. Every effort will be made to encourage female and minority student participation in the conduct of the proposed research.

非破坏性评估的FRP约束混凝土使用微波，CMS项目0324607 PI：口头Buyukozturk，麻省理工学院纤维增强塑料（FRP）复合护套系统已成为替代传统的建设，加强和修复钢筋混凝土柱和桥墩。大量的公共和私人项目都在追求这种技术，预计部署会不断升级，特别是在地震活跃地区。然而，一个高效和有效的结构评估技术，能够评估的具体条件内的玻璃钢护套系统是缺乏的。很明显，一个可靠的混凝土成像技术需要尽快开发赶上激增的工业应用，本研究的目的是开发和应用有效的无损评价（NDE）成像技术，可视化和量化的损伤，如FRP约束钢筋混凝土构件的FRP分层和混凝土开裂和破碎使用宽带雷达。为了实现这一目标，理论模型和图像重建算法的设计将被开发用于测量数据的自动处理，同时在实验室和现场环境中进行物理模型的实验研究。还将建立各种FRP、混凝土和FRP-混凝土混合介质的电磁（EM）特性数据库，以促进这些发展。研究计划包括四个主要任务：（a）波传播和散射的数值模拟，（B）FRP、混凝土和FRP-混凝土混合介质介电性能的测定，（c）物理雷达测量，和（d）信号处理和图像重建。这四个任务在本质上是紧密联系在一起的，并且将以迭代和渐进的方式进行。为此，提出了一种新的宽带雷达数据聚焦方法，用于有效地检测与FRP粘结和约束钢筋混凝土系统相关的各种损伤机制。由于使用宽带雷达检测FRP约束混凝土的损伤的新奇，一个为期一年的探索性研究已经进行了自2002年9月以来，在NSF的小补助金探索性研究（SGER）计划，初步证明本文提出的方法的潜在能力。从迄今为止的探索性工作中，已经取得了可喜的成果。通过本提案，寻求资金来充分开发方法并为实现上述目标进行全面的理论/实验研究。考虑到其非传统的土木工程性质，本项目将综合结构工程，材料科学，电气工程和计算机科学领域的知识和理解。这个多学科的研究项目将与麻省理工学院的土木与环境工程系、电子工程与计算机科学系、电子研究实验室和林肯实验室合作进行。预计拟议的工作将大大推进计算机模拟、创新成像概念、信号处理和图像重建等领域的科学知识。和处理雷达测量的实验室方法。知识的发展作为制造该领域有效设备的基础，将直接影响该行业，并使工程师，交通基础设施社区和全球决策机构受益。应用开发的知识和技术将有助于确保公共安全，防止使用FRP复合材料修复或更新的结构系统发生意外故障。将通过课程研讨会和专业讲习班，将已开发的知识和方法纳入教育。将尽一切努力鼓励女性和少数民族学生参与拟议的研究。