Quantifying the effect of improved school and residential building codes for tornadoes in community resilience

Tornadoes can destroy or severely damage physical infrastructure including buildings in a community.This can result in direct losses but also indirect losses such as the closure of key social institutions reverberating further through the community(e.g.,schools).Despite significant losses in past events,building codes and standards have not previously included tornado hazards because of the relatively low probability of a direct strike.The recent release of the ASCE 7-22 standard considers tornadoes for Risk Category 3 and 4 buildings,i.e.ranging from schools to critical facilities.This study proposes a series of design combinations of a reinforced masonry school building with different performance targets intended to enable schools to reopen sooner.Tornado fragilities were developed for a school building having improved designs using tornado loads determined based on the new tornado chapter in ASCE 7-22,and then integrated into a community level model with school attendance zones to examine the effect.The ultimate goal in this study is to investigate the effect of improving school building designs would have on maintaining school continuity(and more rapid return)for school children.

Multi-disciplinary seismic resilience modeling for developing mitigation policies and recovery planning

The multi-disciplinary data and information available at a community level comprise the foundation of natural hazard resilience modeling.These data enable and inform mitigation and recovery planning decisions prior to and following damaging events such as earthquakes.This paper presents a multi-disciplinary seismic resilience mod-eling methodology to assess the vulnerability of the built environment and economic systems.This methodology can assist decision-makers with developing effective mitigation policies to improve the seismic resilience of com-munities.Two complementary modeling strategies are designed to examine the impacts of scenario earthquakes from a combined engineering and economic perspective.The engineering model is developed using a probabilis-tic fragility-based modeling approach and is analyzed using Monte Carlo(MC)simulations subject to seismic multi-hazard,including simulated ground shaking and resulting liquefaction of the soil,to quantify the physical damage to buildings and electric power substations(EPS).The outcome of the analysis is subsequently used as input to repair and recovery models to quantify repair cost and recovery time metrics for buildings and as input to functionality models to estimate the functionality of individual buildings and substations by accounting for their interdependency.The economic model consists of a spatial computable general equilibrium(SCGE)model that aggregates commercial buildings into sectors for retail,manufacturing,services,etc.,and aggregates residential buildings into a wide range of household groups.The SCGE model employs building functionality estimates to quantify the economic losses.The outcomes of this integrated modeling consist of engineering and economic impact metrics,which are used to investigate mitigation actions to help inform a community on approaches to achieve its resilience goals.An illustrative case study of Salt Lake County(SLC),Utah,developed through an extensive collaborative partnership and engagement with SLC officials,is presented.The results demonstrate the effectiveness of the proposed methodology in quantifying the loss and functional recovery of infrastructure systems,the impacts on capital stock,employment,and household income and the effect of various mitigation strategies in reducing the losses and functional recovery time subject to earthquakes with varying intensities.

Editorial:Integrated modeling of cities to improve natural hazards resilience

Comprehensive resilience modeling of an entire city or commu-nity requires infrastructure models spanning from suites of building archetypes to water and electric power networks,further combined with models of population and the economy.To aid the develop-ment of system-level models and databases to support community re-silience decision-making,a multi-disciplinary team(e.g.,engineering,economics,and social sciences)is needed.

Multi-hazard socio-physical resilience assessment of hurricane-induced hazards on coastal communities

Hurricane-induced hazards can result in significant damage to the built environment cascading into major impacts to the households,social institutions,and local economy.Although quantifying physical impacts of hurricane-induced hazards is essential for risk analysis,it is necessary but not sufficient for community resilience planning.While there have been several studies on hurricane risk and recovery assessment at the building-and community-level,few studies have focused on the nexus of coupled physical and social disruptions,particularly when char-acterizing recovery in the face of coastal multi-hazards.Therefore,this study presents an integrated approach to quantify the socio-physical disruption following hurricane-induced multi-hazards(e.g.,wind,storm surge,wave)by considering the physical damage and functionality of the built environment along with the population dynamics over time.Specifically,high-resolution fragility models of buildings,and power and transportation infrastructures capture the combined impacts of hurricane loading on the built environment.Beyond simulat-ing recovery by tracking infrastructure network performance metrics,such as access to essential facilities,this coupled socio-physical approach affords projection of post-hazard population dislocation and temporal evolution of housing and household recovery constrained by the building and infrastructure recovery.The results reveal the relative importance of multi-hazard consideration in the damage and recovery assessment of communities,along with the role of interdependent socio-physical system modeling when evaluating metrics such as housing recovery or the need for emergency shelter.Furthermore,the methodology presented here provides a foundation for resilience-informed decisions for coastal communities.

Community-Level resilience analysis using earthquake-tsunami fragility surfaces

This study introduces an advanced community-level resilience analysis methodology integrating 3D fragility sur-faces for combined successive earthquake-tsunami hazard and analysis.The methodology facilitates comprehen-sive evaluations of spatial damage,economic loss,and risk under multi-hazard conditions.This study compares earthquake-only analysis results to the successive earthquake-tsunami analysis at the community level to reveal-and quantify-significant disparities in damage and loss estimations between the analyses,emphasizing the need to consider both hazards in community planning even at lower seismic intensities.Critical assessment of the FEMA combinational rule demonstrates its limitations in accurately predicting losses and damage patterns at higher hazard intensities,highlighting the necessity for refined models that accurately account for hazard inter-actions.This research advances multi-hazard community-level resilience analysis by offering a robust framework for earthquake and tsunami assessment,underscoring the need for integration of detailed multi-hazard analy-ses into resilience planning.Finally,it suggests future directions for enhancing framework applicability across diverse community settings and structural types,aiming to improve community resilience.