Collaborative Research: Damage Assessment of Coastal Structures Subject to Waterborne Debris Impact under Extreme Wind and Wave Conditions

随着海平面上升和与天气有关的极端事件更加频繁，沿海民用基础设施和社区正变得更容易发生洪水，因此受到损害和破坏的风险增加。在各种与洪水有关的风险中，洪水携带的碎片可能会对沿海基础设施(如建筑物、房屋和桥梁)造成破坏。这样的碎片(如树木、汽车和轮船)由洪水和海浪携带，通常伴随着极端的阵风。目前，在理解和模拟与洪灾碎片相关的关键物理过程方面存在很大差距。该项目将为了解和预测极端洪水和风力条件下洪水泥石流对建筑物的破坏提供一种科学的方法。这项研究还将得到包括讲习班、课程开发和培训演示在内的教育部分的补充。该奖项将为国家科学基金会(NSF)在国家减少风暴影响计划(NWIRP)中的作用做出贡献。这项研究的主要目标是了解和量化水-风-碎片-结构相互作用中涉及的关键力学过程，包括极端水流和风条件下的碎片漂移、碎片与结构的碰撞以及由此造成的损害。将使用计算流体力学、计算固体力学和实验室实验的多学科方法来实现这一目标。从长远来看，这项研究可以加强对易受洪水和泥石流影响的建筑物的设计和缓解战略，通过发展有弹性的海岸线和社区来增进公众的福祉。

With rising sea-levels and more frequent weather-related extreme events, coastal civil infrastructure and communities are becoming more flood-prone and consequently subject to an elevated risk of damage and destruction. Among the various flood-related risks, flood-borne debris can be destructive to coastal infrastructure (e.g., buildings, houses, and bridges). Such debris (e.g. trees, cars, and ships) are carried by floods and waves, often in combination with extreme wind gusts. Currently, there is a significant gap in understanding and modeling the key physical processes associated with flood-borne debris. This project will provide a science-based approach to understand and predict the flood-borne debris damages to structures under extreme flood flow and wind conditions. The research will also be complemented by an educational component that includes workshops, curriculum development, and training demonstrations. The educational program will be designed to have positive and measurable impact on a broad spectrum of students (ranging from high school to graduate students), foster an increased participation among minority and underrepresented groups, and inform students of the novel research and diverse cultures of the three participating institutions, i.e., Columbia University, SUNY at Stony Brook, and CUNY City College. This award will contribute to the National Science Foundation (NSF) role in the National Windstorm Impact Reduction Program (NWIRP). The overarching goal of this research is to understand and quantify the critical mechanics processes involved in water-wind-debris-structure interactions, including debris drifting by extreme flow and wind conditions, debris collision with the structure, and the resulting damages. A multidisciplinary approach employing computational fluid dynamics, computational solid mechanics, and laboratory experiments will be used to achieve this goal. Specific research tasks include: (1) innovative experiments deploying “smart debris” to investigate wind and transport effects of flood-borne debris and their impact/damage to structures, (2) new computational methods and software for an integrated simulation of debris drifting, impingement, and damage to structures, and (3) novel physics-based fragility curves, at the system level, for structural failure risk assessment due to debris impacts. In the long term, this research can lead to enhanced designs and mitigation strategies for structures susceptible to the impact of flood and debris, advancing the well-being of the public through development of resilient coastlines and communities. Project data will be archived and made publicly available in campus data repositories and in the NSF-supported Natural Hazards Engineering Research Infrastructure Data Depot (https://www.DesignSafe-ci.org).This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.