NEESR-II: Highly Damage Tolerant and Intelligent Slab-Column Frame Systems Through Combination of Advanced Materials and Embedded Wireless Sensing

联合收割机钢筋混凝土（RC）板柱框架与抗弯框架或剪力墙相结合的结构体系在中、高地震活动区得到广泛应用。在地震作用下，板柱节点在自重荷载和侧向位移的共同作用下，容易发生冲切破坏。传统上，板柱连接所需的抗剪强度是通过使用垂板或剪力钉轨道来实现的。本文的主要工作是利用高性能纤维增强水泥基复合材料（HPFRCCs）和无线传感技术，开发一种高损伤容限的智能板柱框架体系.新材料（HPFRCC）和智能结构技术（计算丰富的无线传感器）的发展以前发生在孤立的研究社区-这项建议是第一次探索他们的组合，使智能HPFRCC结构能够承受大漂移的需求和自我性能监测可以派生。NEES基础设施的革命性特征提供了令人兴奋的探索路径，这将导致对智能HPFRCC板柱系统的更深入的研究。为了开发所提出的框架系统，一系列HPFRCC平板试件将首先在密歇根大学进行单调试验，以优化HPFRCC材料的应用。然后将在模拟地震荷载下对组合件进行测试。其中四个子组件将使用明尼苏达大学的NEES-MAST设施进行双向加载。MAST设备非常适合这种应用，因为它可以用于以现实的方式加载板柱组件，以充分评估HPFRCC连接的抗剪能力。这些测试的结果将被用来开发模型，以预测建筑系统的抗震性能，采用这些先进的材料和设计规定的建议板柱连接。为了进一步加强建筑物的安全，无线传感器的新技术将被应用到该项目中，以开发能够自我检测和报告地震事件引起的结构损坏的仪器。NEES-MAST设施提供的高分辨率摄像机将使无线测量与累积损伤密切相关，有助于开发适合这种连接的adamage指数。一个算法的开发损伤指数将嵌入到智能无线传感器跟踪的性能的结构系统，包括自我识别的损伤。施工作业设计研究，通过使用离散eventsimulation，也将进行，以确保拟议system.Intellectual优点的可施工性：拟议工作的结果将是一个高度损伤容限和智能slabcolumnframe系统用于抗震建设。这一创新系统集成了纤维水泥基材料和无线传感技术的最新发展，提供了下一代板柱框架，能够1）抵抗极端动态载荷，具有出色的损伤容限，2）自我识别结构损伤。滞后，损坏和设计模型，校准结果从大型多轴子装配测试，将开发的安全和最佳使用的拟议系统。实验和相关的模型可能最终导致重大的变化，在设计和施工的板柱框架在地区的中等和高地震活动。此外，将开发具有自我检测结构损坏能力的智能无线传感器。更广泛的影响：社会将受益于结构损坏的即时自我识别，因为建筑官员将能够在地震事件发生后立即获得建筑物的累积损坏，并能够对建筑物的剩余生命安全做出更明智的决定。使用NEESgrid功能将允许从建筑和设计专业人员到高中生的一系列访问这项研究。为了鼓励女性和少数民族学生追求工程研究生院的职业生涯，计划与密歇根大学少数民族工程项目办公室和科学与工程项目中的女性一起开展特别活动，例如为感兴趣的女性或少数民族本科生开展夏季研究活动。NEES网格的高科技特征是跨学科研究力量的绝佳例子，并将激励学生考虑结构工程职业。

Structural systems that combine reinforced concrete (RC) slab-column frames with moment resistingframes or shear walls find wide applications in zones of moderate and high seismicity. Due tocombination of lateral displacements imposed during earthquakes with gravity loads, slab-columnconnections are prone to exhibit punching shear failures. Traditionally, the required shear strength of slabcolumn connections is achieved by the use of drop panels or shear stud rails. The work outlined in thisproposal is to develop a highly damage tolerant and smart slab-column frame system through the use ofhigh-performance fiber reinforced cement composites (HPFRCCs) and wireless sensing technology. Thedevelopment of new materials (HPFRCC) and smart structure technologies (computationally rich wirelesssensors) have previously occurred in isolated research communities - this proposal is a first of its kind toexplore their combination so that an intelligent HPFRCC structure capable of sustaining large driftdemands and self-performance monitoring can be derived. The revolutionary features of the NEESinfrastructure offer exciting paths of exploration that will lead to a more profound investigation ofintelligent HPFRCC slab-column systems.In order to develop the proposed frame system, a series of HPFRCC flat slab specimens will be firsttested monotonically at the University of Michigan to optimize the HPFRCC material for this application.A total of six large-scale slab-column sub-assemblages will then be tested under simulated earthquakeloading. Four of these sub-assemblages will be bi-directionally loaded using the NEES-MAST facility atthe University of Minnesota. The MAST facility is ideally suited to this application as it can be used toload slab-column assemblages in a realistic manner to fully assess the shear capacity of HPFRCCconnections. The results of these tests will be used to develop models to predict the seismic behavior ofbuilding systems employing these advanced materials and design provisions for the proposed slab-columnconnections. To further enhance building safety, new technology in wireless sensors will be incorporatedinto the project to develop instruments that can self-detect and report structural damage due to seismicevents. The high resolution cameras available at the NEES-MAST facility will enable the closecorrelation of the wireless measurements with the accumulated damage, aiding in the development of adamage index appropriate for this type of connection. An algorithm for the developed damage index willbe embedded into smart wireless sensors to track the performance of the structural system, including selfidentification of damage. Construction operations design studies, through the use of discrete eventsimulation, will also be conducted to ensure the constructability of the proposed system.Intellectual Merit: The outcome of the proposed work will be a highly damage tolerant and smart slabcolumnframe system for use in seismic-resistant construction. This innovative system integrates the latestdevelopments in fiber cement-based materials and wireless sensing technology to deliver next-generationslab-column frames capable of 1) resisting extreme dynamic loads with outstanding damage tolerance,and 2) self-identifying structural damage. Hysteretic, damage, and design models, calibrated with resultsfrom large-scale multi-axial sub-assemblage tests, will be developed for the safe and optimum use of theproposed system. The experiments and associated models may ultimately lead to significant changes inthe design and construction of slab column frames in areas of moderate and high seismicity. Additionally,smart wireless sensors, with the capability of self-detecting structural damage, will be developed.Broader Impacts: Society will benefit from the immediate self-identification of damage of structures, asbuilding officials will be able to have access to the accumulated damage in a building immediately after aseismic event and will be able to make better informed decisions on the remaining life safety of thebuilding. The use of the NEESgrid capabilities will allow an array of access to this research, fromconstruction and design professionals to high school students. To encourage female and minority students to pursue graduate school careers in engineering, special activities are planned with the University of Michigan's Minorities in Engineering Program Office and the Women in Science and Engineering program such as including summer research activities for interested female or minority undergraduate students. The high-technology features of the NEES grid is a superb example of the power of interdisciplinary research and would motivate students to consider careers in Structural Engineering.