CAREER: A Comprehensive Approach for Investigating the Effects of Near-Fault Dynamic Ground Deformations on Engineering Structures

本学院早期职业发展（Career）计划奖的研究目标是研究近断层动态地面变形对工程结构响应的影响。提出的研究是基于跨学科的方法，范围从震源的描述，地面运动建模，以及动态结构反应。具体研究活动包括：(1)利用数值方法模拟动态地面变形，并评估其在预测近断层区域地面运动的应变、摇晃和扭转分量方面的准确性；(2)利用运动学建模方法研究断层破裂特征对近断层动态地面变形的影响；(3)推导出动态地面变形场某些分量的简化数学模型；(4)研究大跨度桥梁塔架等结构对近断层平移和旋转运动的动力响应；(5)推导近断层区域倾斜和平动耦合地震动响应谱，用于工程分析和设计。通过提供先进的工具和技术来评估工程结构对强震近场动态地面变形的抗震性能，这项研究的见解将对地震工程界产生直接影响。研究结果最终将导致设计规范的改进。这个项目的教育和推广计划包括让大学一级的少数民族和代表性不足的群体参与，并通过K-12的推广活动，扩大他们在数学、科学和工程领域的参与。具体的K-12外展活动包括参加为高中生设计的暑期研究和指导计划，以及为华盛顿特区市区公立高中的学生提供讲座、示范、计算机项目和动手实验室实验。研究成果将发表在学术期刊和会议论文集上，通过项目网站传播，并纳入本科和研究生课程。该项目还将加强地震工程与工程地震学学科之间的互动。综合方法将使科学界能够更好地理解地震问题的本质，更有效地面对研究挑战，以严格的方式将进展纳入工程规范，并最终降低地震风险。

The research objective of this Faculty Early Career Development (CAREER) Program award is to investigate the effects of near-fault dynamic ground deformations on the response of engineering structures. The proposed research is based on an interdisciplinary approach that ranges from the description of the earthquake source, to ground motion modeling, and to dynamic structural response. Specific research activities include: (1) simulating dynamic ground deformations using numerical approaches, and evaluating their accuracy in predicting strain, rocking and torsional components of ground motion in the near-fault region, (2) investigating the effect of fault rupture characteristics on near-fault dynamic ground deformations using a kinematic modeling approach, (3) deriving simplified mathematical models for the representation of certain components of the dynamic ground deformation field, (4) investigating the dynamic response of structures such as towers of long-span bridges to near-fault translational and rotational motions, and (5) deriving coupled tilt and translational ground motion response spectra for engineering analysis and design in the near-fault region.Insights from this research will have a direct impact on the earthquake engineering community, by providing advanced tools and techniques for assessing the seismic performance of engineering structures to dynamic ground deformations in the near field of strong earthquakes. Research results will ultimately lead to improvements in design codes. The education and outreach plan of this project includes the involvement of minorities and underrepresented groups at the university level and through K-12 outreach activities with the objective of broadening their participation in the fields of mathematics, science and engineering. Specific K-12 outreach activities include participation in summer research and mentoring programs designed for high school students, as well as lectures, demonstrations, computer projects and hands-on laboratory experiments to students at public high schools in the Washington, DC metropolitan area. Research results will be published in scholarly journals and conference proceedings, disseminated through a project website, and integrated into undergraduate and graduate courses. The project will also strengthen interactions between the earthquake engineering and engineering seismology disciplines. An integrated approach will enable the scientific community to better understand the nature of the earthquake problem, face the research challenges more effectively, incorporate the progress into engineering codes in a rigorous way, and ultimately reduce the seismic risk.