CAREER: Innovative Confinement Technology for Strong Main Shock-Aftershock Damage Mitigation

这项教师早期职业发展（Career）计划的目标是减轻损害，提高钢筋混凝土桥梁在中至强地震及其余震中的坚固性和功能。为了控制损伤，该项目将研究一种新的混凝土约束技术的应用，该技术利用形状记忆合金（sma）作为横向钢筋。这项新技术利用了主动约束的概念。本项目拟开展的研究活动包括：(1)对受新钢筋约束的混凝土单元进行多轴单调和循环试验。(2)建立具有增强损伤预测特征的SMA约束混凝土三维塑性通用模型。(3)通过伊利诺斯州真实桥梁的室内试验和现场试验，检验SMA加固的耐久性和长期性能。(4)建立包括中强主震和一系列余震的真实地震灾害情景模型。(5)进行地震损伤分析，绘制新技术加固桥梁的易损性曲线。(6)对采用新型约束技术加固的钢筋混凝土小比例尺桥墩进行验证性混合模拟试验。该项目将为地震工程界提供有关新约束技术的关键、深入的信息。它将解决建模、耐久性和设计问题，这些问题对于该技术发挥其全部潜力至关重要，可以立即解决地震后功能、停机时间和关键生命线桥梁的修复成本问题。该项目的成果将通过伊利诺伊大学厄巴纳-香槟分校的两门研究生混凝土设计课程直接传播给研究生和高级土木工程专业的学生。为了鼓励和促进来自土木工程领域代表性不足群体的K-12学生的参与，这笔奖金的一部分将用于为女高中生组织一年一度的夏令营。为了提高在职桥梁工程师对这项新技术的认识，PI将组织一个研讨会，向这群工程师传播项目成果。该项目还将向地震研究界推广该项目中使用的新型混合模拟测试技术。最后，本研究也将提高研究和实务团体对强地震余震对土木工程结构设计影响的认识。

The objective of this Faculty Early Career Development (CAREER) Program award is to mitigate damage and to enhance the robustness and functionality of reinforced concrete bridges subjected to moderate-to-strong earthquakes and their aftershocks. For damage-control, the project will investigate the application of a new concrete confinement technology utilizing the shape memory alloys (SMAs) as the transverse reinforcement. This new technology capitalizes on the concept of active confinement. The research activities planned for this project include: (1) Conducting multi-axial monotonic and cyclic tests on concrete elements confined with the new reinforcement. (2) Developing general 3-dimensional plasticity model for concrete confined with SMA reinforcement with enhanced damage prediction feature. (3) Examining the durability and long-term performance of SMA reinforcement through laboratory tests and field tests conducted on real bridges in Illinois. (4) Developing models for realistic seismic hazard scenarios comprising moderate-to-strong main shock followed by a series of aftershocks. (5) Conducting seismic damage analyses to develop fragility curves for bridges reinforced with the new technology. (6) Conducting confirmatory hybrid simulation tests on reduced-scale reinforced concrete bridge piers strengthened with the new confinement technology. This project will provide the earthquake engineering community with critical, in-depth, information about the new confinement technology. It will address the modeling, durability, and design issues that are crucial for this technology to reach its full potential in delivering immediate solutions to the problems of post-earthquake functionality, down time, and repair costs of critical lifeline bridges. The results of this project will be directly disseminated to the graduate and senior level civil engineering students through two graduate level concrete design courses taught at the University of Illinois, Urbana-Champaign. To encourage and promote the involvement of K-12 students from underrepresented groups in the field of Civil Engineering, a part of this award will be directed to organize an annual summer camp for female high school students. To increase the awareness of this new technology among the practicing bridge engineers, the PI will organize a workshop to disseminate the project results to this group of engineers. The project will also promote the new hybrid simulation testing technique used in this project to the seismic research community. Finally, this project will also increase the awareness among the research and practitioner communities about the impacts of strong earthquake aftershocks on the design of civil engineering structures.