There has been a large increase in the number of days per year with numerous EF1-EF5 tornadoes.Given the significant damage incurred by tornadoes upon communities,community resilience analyses for tornado-stricken com...There has been a large increase in the number of days per year with numerous EF1-EF5 tornadoes.Given the significant damage incurred by tornadoes upon communities,community resilience analyses for tornado-stricken communities have been gaining momentum.As the community resilience analysis aims to guide how to lay out effective hazard mitigation strategies to decrease damage and improve recovery,a comprehensive and accurate approach is necessary.Agent-based modeling,an analysis approach in which different types of agents are created with their properties and behavior clearly defined to simulate the processes of those agents in an external environ-ment,is the most comprehensive and accurate approach so far to conducting community resilience simulations and investigating the decision-making for mitigation and recovery under natural hazards.In this paper,agent-based models(ABMs)are created to simulate the recovery process of a virtual testbed based on the real-world community in Joplin City,MO.The tornado path associated with the real-world tornado event that occurred in May 2011 is adopted in the tornado hazard modeling for the Joplin testbed.In addition,agent-based models are created for another virtual community in the Midwest United States named Centerville using an assumed tornado scenario of the same EF-scale as that in Joplin.The effects of hazard mitigation strategies on the two communities are also explored.A comparison between the analysis results of these two testbeds can indicate the influence of the characteristics of a tornado-prone community on the resilience of the community as well as on the effects of hazard mitigation strategies.It is observed that a community’s level of development significantly impacts the tornado resilience.In addition,the effects of a specific type of hazard mitigation strategy on the recovery process are contingent upon testbed characteristics.展开更多
A large number of communities are impacted annually by the increasing frequency of tornado hazards resulting in damage to the infrastructure as well as disruption of community functions.The effect of the hazard geomet...A large number of communities are impacted annually by the increasing frequency of tornado hazards resulting in damage to the infrastructure as well as disruption of community functions.The effect of the hazard geometry(center and angle of tornado path as well as the tornado width)is studied herein on how it influences the recovery of physical and social systems within the community.Given that pre-disaster preparedness including mitigation strategies(e.g.,retrofits)and policies(e.g.,insurance)is crucial for increasing the resilience of the community and facilitating a faster recovery process,in this study,the impact of various mitigation strategies and policies on the recovery trajectory and resilience of a typical US community subjected to a tornado is investigated considering different sources of uncertainties.The virtual testbed of Centerville is selected in this paper and is modeled by adopting the Agent-based modeling(ABM)approach which is a powerful tool for conducting community resilience analysis that simulates the behavior of different types of agents and their interactions to capture their interdependencies.The results are presented in the form of recovery time series as well as calculated resilience indices for various community systems(lifeline networks,schools,healthcare,businesses,and households).The results of this study can help deepen our understanding of how to efficiently expedite the recovery process of a community.展开更多
The community’s resilience in the face of natural hazards relies heavily on the rapid and efficient restoration of electric power networks,which plays a critical role in emergency response,economic recovery,and the f...The community’s resilience in the face of natural hazards relies heavily on the rapid and efficient restoration of electric power networks,which plays a critical role in emergency response,economic recovery,and the func-tionality of essential lifeline and social infrastructure systems.Leveraging the recent data revolution,the digital twin(DT)concept emerges as a promising tool to enhance the effectiveness of post-disaster recovery efforts.This paper introduces a novel framework for post-hurricane electric power restoration using a hybrid DT approach that combines physics-based and data-driven models by utilizing a dynamic Bayesian network.By capturing the complexities of power system dynamics and incorporating the road network’s influence,the framework offers a comprehensive methodology to guide real-time power restoration efforts in post-disaster scenarios.A discrete event simulation is conducted to demonstrate the proposed framework’s efficacy.The study showcases how the electric power restoration DT can be monitored and updated in real-time,reflecting changing conditions and facilitating adaptive decision-making.Furthermore,it demonstrates the framework’s flexibility to allow decision-makers to prioritize essential,residential,and business facilities and compare different restoration plans and their potential effect on the community.展开更多
Experience from past earthquakes has demonstrated the need to account for design goals beyond safety,known as functional recovery objectives,in the interest of community resilience.Frameworks have been proposed in the...Experience from past earthquakes has demonstrated the need to account for design goals beyond safety,known as functional recovery objectives,in the interest of community resilience.Frameworks have been proposed in the literature to assess the post-earthquake functional recovery of a building,but without accounting for utility systems’disruption,which may be a key contributor to determining when a building is functional.This paper integrates a previously proposed probabilistic method for estimating the post-earthquake restoration of critical utility services with an individual building’s functional recovery assessment framework.The integration was performed by incorporating utilities into the building system fault trees embedded into a functional recovery framework for various building occupancies(residential and commercial office buildings).Once incorporated,the results are used to interrogate the functional recovery of a reinforced concrete building,and the recovery time results were presented for seven cases investigating contributing factors in the functional recovery results including the number of crews available for lifeline restoration,the effect of low-quality service on meeting tenant requirements for elevators,heating ventilation and air conditioning(HVAC),plumbing and electrical systems,consideration of fire watch,the effect of building seismic retrofit,as well as different cases of fragility functions for the lifeline systems.Results showed that utility systems’disruption does not have a significant impact on the recoccupancy of a building because only one utility-dependent building system(fire suppression)is needed for the building’s safety.Unlike reoccupancy,utility systems are significant for functional recovery,mainly at moderate hazard levels because,at these levels,lifeline networks could be damaged without significant building damage,such that the lifeline systems restoration governs.Buildings with more restrictive tenant requirements are more sensitive to tenant disruptions.展开更多
An increased number of hurricanes and tornadoes have been recorded worldwide in the last decade,while research efforts to reduce wind-related damage to structures become essential.Freeform architecture,which focuses o...An increased number of hurricanes and tornadoes have been recorded worldwide in the last decade,while research efforts to reduce wind-related damage to structures become essential.Freeform architecture,which focuses on generating complex curved shapes including streamlined shapes,has recently gained interest.This study focuses on investigating the potential of kerf panels,which have unique flexibility depending on the cut patterns and densities,to generate complex shapes for facades and their performance under wind loads.To investigate the kerf panel's potential capacity against wind loads,static and dynamic analyses were conducted for two kerf panel types with different cut densities and pre-deformed shapes.It was observed that although solid panels result in smaller displacement amplitudes,stresses,and strains in some cases,the kerf panels allow for global and local cell deformations resulting in stress reduction in various locations with the potential to reduce damage due to overstress in structures.For the predeformed kerf panels,it was observed that both the overall stress and strain responses in kerf cut arrangements were lower than those of the flat-shaped panels.This study shows the promise of the use of kerf panels in achieving both design flexibility and performance demands when exposed to service loadings.Considering that this newly proposed architectural configuration(design paradigm)for facades could revolutionize structural engineering by pushing complex freeform shapes to a standard practice that intertwines aesthetic arguments,building performance requirements,and material design considerations has the potential for significant practical applications.展开更多
基金Financial support for this work was provided by the US Department of Commerce,the National Institute of Standards and Technology(NIST)under the Financial Assistance Award Number#70NANB20H008the US National Science Foundation(NSF)under Award Number 2052930.
文摘There has been a large increase in the number of days per year with numerous EF1-EF5 tornadoes.Given the significant damage incurred by tornadoes upon communities,community resilience analyses for tornado-stricken communities have been gaining momentum.As the community resilience analysis aims to guide how to lay out effective hazard mitigation strategies to decrease damage and improve recovery,a comprehensive and accurate approach is necessary.Agent-based modeling,an analysis approach in which different types of agents are created with their properties and behavior clearly defined to simulate the processes of those agents in an external environ-ment,is the most comprehensive and accurate approach so far to conducting community resilience simulations and investigating the decision-making for mitigation and recovery under natural hazards.In this paper,agent-based models(ABMs)are created to simulate the recovery process of a virtual testbed based on the real-world community in Joplin City,MO.The tornado path associated with the real-world tornado event that occurred in May 2011 is adopted in the tornado hazard modeling for the Joplin testbed.In addition,agent-based models are created for another virtual community in the Midwest United States named Centerville using an assumed tornado scenario of the same EF-scale as that in Joplin.The effects of hazard mitigation strategies on the two communities are also explored.A comparison between the analysis results of these two testbeds can indicate the influence of the characteristics of a tornado-prone community on the resilience of the community as well as on the effects of hazard mitigation strategies.It is observed that a community’s level of development significantly impacts the tornado resilience.In addition,the effects of a specific type of hazard mitigation strategy on the recovery process are contingent upon testbed characteristics.
基金Financial support for this work was provided by the US Department of Commerce,National Institute of Standards and Technology(NIST)under the Financial Assistance Award Number(FAIN)#70NANB20H008.
文摘A large number of communities are impacted annually by the increasing frequency of tornado hazards resulting in damage to the infrastructure as well as disruption of community functions.The effect of the hazard geometry(center and angle of tornado path as well as the tornado width)is studied herein on how it influences the recovery of physical and social systems within the community.Given that pre-disaster preparedness including mitigation strategies(e.g.,retrofits)and policies(e.g.,insurance)is crucial for increasing the resilience of the community and facilitating a faster recovery process,in this study,the impact of various mitigation strategies and policies on the recovery trajectory and resilience of a typical US community subjected to a tornado is investigated considering different sources of uncertainties.The virtual testbed of Centerville is selected in this paper and is modeled by adopting the Agent-based modeling(ABM)approach which is a powerful tool for conducting community resilience analysis that simulates the behavior of different types of agents and their interactions to capture their interdependencies.The results are presented in the form of recovery time series as well as calculated resilience indices for various community systems(lifeline networks,schools,healthcare,businesses,and households).The results of this study can help deepen our understanding of how to efficiently expedite the recovery process of a community.
基金Financial support for this work was provided by the US National Science Foundation(NSF)under Award Number 2052930.
文摘The community’s resilience in the face of natural hazards relies heavily on the rapid and efficient restoration of electric power networks,which plays a critical role in emergency response,economic recovery,and the func-tionality of essential lifeline and social infrastructure systems.Leveraging the recent data revolution,the digital twin(DT)concept emerges as a promising tool to enhance the effectiveness of post-disaster recovery efforts.This paper introduces a novel framework for post-hurricane electric power restoration using a hybrid DT approach that combines physics-based and data-driven models by utilizing a dynamic Bayesian network.By capturing the complexities of power system dynamics and incorporating the road network’s influence,the framework offers a comprehensive methodology to guide real-time power restoration efforts in post-disaster scenarios.A discrete event simulation is conducted to demonstrate the proposed framework’s efficacy.The study showcases how the electric power restoration DT can be monitored and updated in real-time,reflecting changing conditions and facilitating adaptive decision-making.Furthermore,it demonstrates the framework’s flexibility to allow decision-makers to prioritize essential,residential,and business facilities and compare different restoration plans and their potential effect on the community.
基金Financial support for this work was provided by the US Depart-ment of Commerce,National Institute of Standards and Technology un-der the Financial Assistance Award Number#70NANB19H058.
文摘Experience from past earthquakes has demonstrated the need to account for design goals beyond safety,known as functional recovery objectives,in the interest of community resilience.Frameworks have been proposed in the literature to assess the post-earthquake functional recovery of a building,but without accounting for utility systems’disruption,which may be a key contributor to determining when a building is functional.This paper integrates a previously proposed probabilistic method for estimating the post-earthquake restoration of critical utility services with an individual building’s functional recovery assessment framework.The integration was performed by incorporating utilities into the building system fault trees embedded into a functional recovery framework for various building occupancies(residential and commercial office buildings).Once incorporated,the results are used to interrogate the functional recovery of a reinforced concrete building,and the recovery time results were presented for seven cases investigating contributing factors in the functional recovery results including the number of crews available for lifeline restoration,the effect of low-quality service on meeting tenant requirements for elevators,heating ventilation and air conditioning(HVAC),plumbing and electrical systems,consideration of fire watch,the effect of building seismic retrofit,as well as different cases of fragility functions for the lifeline systems.Results showed that utility systems’disruption does not have a significant impact on the recoccupancy of a building because only one utility-dependent building system(fire suppression)is needed for the building’s safety.Unlike reoccupancy,utility systems are significant for functional recovery,mainly at moderate hazard levels because,at these levels,lifeline networks could be damaged without significant building damage,such that the lifeline systems restoration governs.Buildings with more restrictive tenant requirements are more sensitive to tenant disruptions.
基金This study is funded by the US National Science Foundation(NSF)under Award Nos.CMMI 1912823 and 1913688.
文摘An increased number of hurricanes and tornadoes have been recorded worldwide in the last decade,while research efforts to reduce wind-related damage to structures become essential.Freeform architecture,which focuses on generating complex curved shapes including streamlined shapes,has recently gained interest.This study focuses on investigating the potential of kerf panels,which have unique flexibility depending on the cut patterns and densities,to generate complex shapes for facades and their performance under wind loads.To investigate the kerf panel's potential capacity against wind loads,static and dynamic analyses were conducted for two kerf panel types with different cut densities and pre-deformed shapes.It was observed that although solid panels result in smaller displacement amplitudes,stresses,and strains in some cases,the kerf panels allow for global and local cell deformations resulting in stress reduction in various locations with the potential to reduce damage due to overstress in structures.For the predeformed kerf panels,it was observed that both the overall stress and strain responses in kerf cut arrangements were lower than those of the flat-shaped panels.This study shows the promise of the use of kerf panels in achieving both design flexibility and performance demands when exposed to service loadings.Considering that this newly proposed architectural configuration(design paradigm)for facades could revolutionize structural engineering by pushing complex freeform shapes to a standard practice that intertwines aesthetic arguments,building performance requirements,and material design considerations has the potential for significant practical applications.
