Collaborative Research: Damage Compliant Inelastic Design Parameters for Performance-Based-Seismic-Design of Slender RC Columns

该奖项的研究目标是开发和校准非弹性建模参数，以更好地将损伤与细长钢筋混凝土（RC）桥梁柱的性能相关联。要研究的具体建模参数是所谓的塑性铰长度，它有助于与非弹性行为相关的设计和分析任务。该方法将采用基于力学的方法，并从简单的计算工具，以高保真度建模的RC柱的非弹性响应的进展。将这些计算工具与具有精确局部测量的严格实验程序联系起来，将为验证和校准新的基于力学的模型提供必要的数据。这项研究将导致新的校准/验证的塑性铰长度模型与改进的相关性和/或符合当地的损坏，在地震荷载作用下，在钢筋混凝土桥梁柱的发展。可扩展性包括用于定义塑性铰长度的新模型，该模型平衡了设计便利性和力学分析的严格性，同时提供了与损坏相关的能力的准确性。抗震设计的当前技术水平正朝着规定与明确定义的损伤水平相关的局部应变水平的方向发展。如果成功的话，研究将提供有价值的数值工具，从业者和研究人员使用的评估/设计RC柱在这个新兴的设计理念。该研究将为基于性能的设计中的非弹性建模创建一个统一的框架，该框架将适用于桥梁和建筑结构中的一系列柱尺寸。研究结果将存入开放存取的资料库，供他人使用。将为本科生和研究生创建虚拟结构测试实验室等教育资源，以促进他们的学习。计划为K-12学生和大一工程专业学生开展外联活动。PI将利用REU补充资金的项目，专门针对代表性不足的学生提供夏季研究奖学金。

The research objective of this award is to develop and calibrate inelastic modeling parameters that better correlate damage to performance of slender reinforced concrete (RC) bridge columns. The specific modeling parameter to be investigated is the so-called plastic hinge length, which facilitates design and analysis tasks related to inelastic behavior. The approach will employ a mechanics-based methodology and progress from simple computational tools to high-fidelity modeling of the inelastic response of RC columns. Linking of these computational tools to a rigorous experimental program with accurate localized measurements will provide the necessary data to validate and calibrate the new mechanics-based models. The research will result in newly calibrated/validated plastic hinge length models with improved correlation and/or compliance with local damage that develop in RC bridge columns during seismic loads. Deliverables include new models for defining plastic hinge length that balance the design convenience and the analytical rigor of mechanics, while providing accuracy in their ability to relate to damage. Current state of the art in seismic design is moving towards prescribing localized strain levels that correlate to a well-defined damage level. If successful, the research will provide valuable numerical tools for practitioners and researchers to use in the assessment/design of RC columns within this emerging design philosophy. The research will create a unifying framework for inelastic modeling in performance based design, which will be applicable to a range of column sizes in bridge and building structures. Research results will be archived in open-access repositories for utilization by others. Educational resources for undergraduate and graduate students such as a virtual structural testing laboratory will be created to facilitate their learning. Outreach activities are planned for K-12 students and freshmen engineering students. The PIs will leverage the project with REU supplementary funding for summer research fellowships exclusively targeted at underrepresented students.