Probabilistic Performance-Based Hurricane Engineering (PBHE) Framework

In modern times, hurricanes have caused enormous losses to the communities worldwide both in terms of property damage and loss of life. In light of these losses, a comprehensive methodology is required to improve the quantification of risk and the design of structures subject to hurricane hazard. This research develops a probabilistic Performance-Based Hurricane Engineering (PBHE) framework for hurricane risk assessment. The proposed PBHE is based on the total probability theorem, similar to the Performance-Based Earthquake Engineering (PBEE) framework developed by the Pacific Earthquake Engineering Research (PEER) Center, and to the Performance-Based Wind Engineering (PBWE) framework. The methodology presented in this research disaggregates the risk assessment analysis into independent elementary components, namely hazard analysis, structural characterization, interaction analysis, structural analysis, damage analysis, and loss analysis. It also accounts for the multi-hazard nature of hurricane events by including the separate effects of, as well as the interaction among, hurricane wind, flood, windborne debris, and rainfall hazards. This research uses the Performance-Based Hurricane Engineering (PBHE) framework with multi-layer Monte Carlo Simulation (MCS) for the loss analysis of structures subject to hurricane hazard. The interaction of different hazard sources is integrated into the framework and their effect on the risk assessment of non-engineered structures, such as low-rise residential buildings, is investigated. The performance of popular storm mitigation techniques and design alternatives for residential buildings are also compared from a cost-benefit perspective. Finally, the PBHE framework is used for risk assessment of engineered structures, such as tall buildings. The PBHE approach introduced in this study represents a first step toward a rational methodology for risk assessment and design of structures subjected to multi-hazard scenarios

Geodatabase-assisted storm surge modeling

Tropical cyclone-generated storm surge frequently causes catastrophic damage in communities along the Gulf of Mexico. The prediction of landfalling or hypothetical storm surge magnitudes in U.S. Gulf Coast regions remains problematic, in part, because of the dearth of historic event parameter data, including accurate records of storm surge magnitude (elevation) at locations along the coast from hurricanes. While detailed historical records exist that describe hurricane tracks, these data have rarely been correlated with the resulting storm surge, limiting our ability to make statistical inferences, which are needed to fully understand the vulnerability of the U.S. Gulf Coast to hurricane-induced storm surge hazards. This dissertation addresses the need for reliable statistical storm surge estimation by proposing a probabilistic geodatabase-assisted methodology to generate a storm surge surface based on hurricane location and intensity parameters on a single desktop computer. The proposed methodology draws from a statistically representative synthetic tropical cyclone dataset to estimate hurricane track patterns and storm surge elevations. The proposed methodology integrates four modules: tropical cyclone genesis, track propagation, storm surge estimation, and a geodatabase. Implementation of the developed methodology will provide a means to study and improve long-term tropical cyclone activity patterns and predictions. Specific contributions are made to the current state of the art through each of the four modules. In the genesis module, improved representative data from historical genesis populations are achieved through implementation of a stratified-Monte-Carlo sampling method to simulate genesis locations for the North Atlantic Basin, avoiding potential non-representative clustering of sampled genesis locations. In the track module, the improved synthetic genesis locations are used as the starting point for a track location and intensity methodology that incorporates storm strength parameters into the synthetic tracks and improves the positional quality of synthetic tracks. In the surge module, high-resolution, computationally intensive storm surge model results are probabilistically integrated in a computationally fast-running platform. In the geodatabase module, historic and synthetic tropical cyclone genesis, track, and surge elevation data are combined for efficient storage and retrieval of storm surge data

Integrated Sustainability and Resiliency Assessment Methodology for the Design of Single-Family Residential Structures Subject to Wind and Flood Hazards

Sustainability and resiliency have become important in shaping the criteria in performance-based design objectives in the recent past and will continue to shape future design as climate change impacts and disasters become more prevalent. While much work has been carried out in developing tools to aid in sustainable and resilient performance-based design there is still much work to be done. It is evident that while sustainability and resiliency have mutual advantages there are also inherent conflicts between the two design approaches. Some of the conflict relates to the robustness required of resilient design, which may have higher environmental impacts than traditional construction. Other conflicts have resulted from addressing these two design goals using separate tools and approaches rather than addressing them simultaneously through an integrated design process. This means there is the potential today for sustainable buildings to be constructed that are either vulnerable to hazards, which are avoidable, or resilient buildings that could be designed to be more sustainable. Weighing cost and structural performance has been an integral part of engineering design, and in similar ways intersections between environmental impact and structural performance can be addressed. However, sustainable and resilient development principals need to be better integrated together within design process so that intersections between the two can be identified and tradeoffs can be weighed. The models proposed in this dissertation are potential tools where sustainable and resilient design can be optimized within the context of the design and construction of coastal, single-family residential (SFR) structures subject to wind and flood hazards. Optimization is accomplished through the consideration of the environmental impacts of SFR buildings and by comparing alternate designs with varying levels of resilience. The comparison is based on multiple environmental impact metrics which are measured for key phases of the building’s life-cycle. Identifying the optimal design aides the designer in making objective, performance-based design decisions

Typhoon fragility analysis and climate change impact assessment of Filipino cultural heritage asset roofs

Cultural Heritage (CH) assets are especially vulnerable to natural hazards (e.g., earthquake-induced ground shaking, typhoon-induced strong wind, and flooding) due to the lack of hazard-resistant features and to aging-induced extensive structural degradation. These considerations, together with their high historical/cultural value, justify the prioritization/implementation of disaster risk reduction (DRR) and resilience-enhancing strategies for the preservation of such assets. This paper proposes a probabilistic, simulation-based framework for the derivation of wind fragility relationships for CH roofs. Roof-panel pullout and pullover failure modes are used to model the progressive failure of the roof system, thus enabling the integration of fastener corrosion effects and load redistribution into the proposed fragility model. Monte-Carlo sampling is used to propagate the uncertainties related to wind-induced demands and roof component (i.e., fasteners and panels) capacities. Climate projections are used to assess the impact of climate change on wind hazard variations, and ultimately on the asset wind risk profile over time. An illustrative application of the proposed procedure is presented with reference to 25 heritage buildings in Iloilo City, Philippines

Technology and Management for Sustainable Buildings and Infrastructures

A total of 30 articles have been published in this special issue, and it consists of 27 research papers, 2 technical notes, and 1 review paper. A total of 104 authors from 9 countries including Korea, Spain, Taiwan, USA, Finland, China, Slovenia, the Netherlands, and Germany participated in writing and submitting very excellent papers that were finally published after the review process had been conducted according to very strict standards. Among the published papers, 13 papers directly addressed words such as sustainable, life cycle assessment (LCA) and CO2, and 17 papers indirectly dealt with energy and CO2 reduction effects. Among the published papers, there are 6 papers dealing with construction technology, but a majority, 24 papers deal with management techniques. The authors of the published papers used various analysis techniques to obtain the suggested solutions for each topic. Listed by key techniques, various techniques such as Analytic Hierarchy Process (AHP), the Taguchi method, machine learning including Artificial Neural Networks (ANNs), Life Cycle Assessment (LCA), regression analysis, Strength–Weakness–Opportunity–Threat (SWOT), system dynamics, simulation and modeling, Building Information Model (BIM) with schedule, and graph and data analysis after experiments and observations are identified

Atmospheric Hazards

Natural and environmental hazards research comprises a diverse set of subjects and methodologies and this book is no exception - offering the reader only a small glimpse into the physical and social processes that threaten human interests. Atmospheric Hazards-Case Studies in Modeling, Communication, and Societal Impacts explores atmospheric-based hazards through focused investigations ranging from a local to global perspective. Within this short compendium, the major scales of atmospheric motion are well represented with topics on microscale turbulent transport of pollutants, mesoscale events stemming from thunderstorm complexes, and synoptic scale extreme precipitation episodes. Chapters include discussions on modeling aspects for investigating hazards (pollution, regional climate models) and the forecasting and structure of high wind events (derechos), whereas others delve into hazard communication, preparedness, and social vulnerability issues (tornadoes, hurricanes, and lightning). Although the chapters are quite disparate upon first inspection, the topics are united through their interweaving of both the physical and societal mechanisms that create the atmospheric hazard and eventual disaster

Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation: Special Report of the Intergovernmental Panel on Climate Change

This Special Report on Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation (SREX) has been jointly coordinated by Working Groups I (WGI) and II (WGII) of the Intergovernmental Panel on Climate Change (IPCC). The report focuses on the relationship between climate change and extreme weather and climate events, the impacts of such events, and the strategies to manage the associated risks. The IPCC was jointly established in 1988 by the World Meteorological Organization (WMO) and the United Nations Environment Programme (UNEP), in particular to assess in a comprehensive, objective, and transparent manner all the relevant scientific, technical, and socioeconomic information to contribute in understanding the scientific basis of risk of human-induced climate change, the potential impacts, and the adaptation and mitigation options. Beginning in 1990, the IPCC has produced a series of Assessment Reports, Special Reports, Technical Papers, methodologies, and other key documents which have since become the standard references for policymakers and scientists.This Special Report, in particular, contributes to frame the challenge of dealing with extreme weather and climate events as an issue in decisionmaking under uncertainty, analyzing response in the context of risk management. The report consists of nine chapters, covering risk management; observed and projected changes in extreme weather and climate events; exposure and vulnerability to as well as losses resulting from such events; adaptation options from the local to the international scale; the role of sustainable development in modulating risks; and insights from specific case studies

WUDAPT: an urban weather, climate and environmental modeling infrastructure for the Anthropocene

WUDAPT is an international community-based initiative to acquire and disseminate climate relevant data on the physical geographies of cities for modeling and analyses purposes. The current lacuna of globally consistent information on cities is a major impediment to urban climate science towards informing and developing climate mitigation and adaptation strategies at urban scales. WUDAPT consists of a database and a portal system; its database is structured into a hierarchy representing different levels of detail and the data are acquired using innovative protocols that utilize crowdsourcing approaches, Geowiki tools, freely accessible data, and building typology archetypes. The base level of information (L0) consists of Local Climate Zones (LCZ) maps of cities; each LCZ category is associated with range of values for model relevant surface descriptors (e.g. roughness, impervious surface cover, roof area, building heights, etc.). Levels 1 (L1) and 2 (L2) will provide specific intraurban values for other relevant descriptors at greater precision, such as data morphological forms, material composition data and energy usage. This article describes the status of the WUDAPT project and demonstrates its potential value using observations and models. As a community-based project, other researchers are encouraged to participate to help create a global urban database of value to urban climate scientists

Probabilistic-based hurricane risk assessment and mitigation considering the potential impacts of climate change

Studies are suggesting that hurricane hazard patterns (e.g. intensity and frequency) may change as a consequence of the changing global climate. As hurricane patterns change, it can be expected that hurricane damage risks and costs may change as a result. This indicates the necessity to develop hurricane risk assessment models that are capable of accounting for changing hurricane hazard patterns, and develop hurricane mitigation and climatic adaptation strategies. This thesis proposes a comprehensive hurricane risk assessment and mitigation strategies that account for a changing global climate and that has the ability of being adapted to various types of infrastructure including residential buildings and power distribution poles. The framework includes hurricane wind field models, hurricane surge height models and hurricane vulnerability models to estimate damage risks due to hurricane wind speed, hurricane frequency, and hurricane-induced storm surge and accounts for the timedependant properties of these parameters as a result of climate change. The research then implements median insured house values, discount rates, housing inventory, etc. to estimate hurricane damage costs to residential construction. The framework was also adapted to timber distribution poles to assess the impacts climate change may have on timber distribution pole failure. This research finds that climate change may have a significant impact on the hurricane damage risks and damage costs of residential construction and timber distribution poles. In an effort to reduce damage costs, this research develops mitigation/adaptation strategies for residential construction and timber distribution poles. The costeffectiveness of these adaptation/mitigation strategies are evaluated through the use of a Life-Cycle Cost (LCC) analysis. In addition, a scenario-based analysis of mitigation strategies for timber distribution poles is included. For both residential construction and timber distribution poles, adaptation/mitigation measures were found to reduce damage costs. Finally, the research develops the Coastal Community Social Vulnerability Index (CCSVI) to include the social vulnerability of a region to hurricane hazards within this hurricane risk assessment. This index quantifies the social vulnerability of a region, by combining various social characteristics of a region with time-dependant parameters of hurricanes (i.e. hurricane wind and hurricane-induced storm surge). Climate change was found to have an impact on the CCSVI (i.e. climate change may have an impact on the social vulnerability of hurricane-prone regions)