The purpose of this paper is to identify the critical road sections and intersections in a road network which have great influence on the normal transport functions of the road network and to optimize the road network...The purpose of this paper is to identify the critical road sections and intersections in a road network which have great influence on the normal transport functions of the road network and to optimize the road network structure by reducing its vulnerability. In this paper, the framework of road network structural vulnerability measurement and improvement model is proposed. The network efficiency model is used to define road network structural vulnerability. Shanghai freeway network is analyzed based on this model. We find that using this model the critical components of the road network can be identified. Two methods which are increasing connections and rewiring are proposed to optimize the road network structural vulnerability and the results can be used to reduce the network vulnerability. The measurement method that we put forward for structure vulnerability is useful and important to optimize road network structure.展开更多
The damage of dwelling houses constitutes the primary cause of casualties and asset loss in seismic disasters that occurred in Chinese rural areas. The structure of houses is crucial for assessing the vulnerability of...The damage of dwelling houses constitutes the primary cause of casualties and asset loss in seismic disasters that occurred in Chinese rural areas. The structure of houses is crucial for assessing the vulnerability of rural houses. However, at present, available data on rural housing structure are incomplete and their spatial scales are inconsistent. This paper estimated the amount and ratio of rural houses in five structures, namely ＇wood＇, ＇brick＇, ＇mixed＇, ＇reinforced concrete＇, and ＇other＇, for 2380 counties across China. With the percent- age sampling census data in 2005, four accuracy levels were specified. Then, a set of down-scaling models were established, where the impact of climate, economic development level and ethnic minority cultural factors on rural housing structure, as well as the spatial autocorrelation of neighboring spatial units were considered. Based on the estimation results, a database of county-level rural housing structure was established, based on which the vul- nerability of rural houses in different areas was clarified.展开更多
The spatial distribution of the world population is uneven,with a density of about 40%living in coastal regions.The trend is expected to continue in both demographic indicators and urban development rate,being many co...The spatial distribution of the world population is uneven,with a density of about 40%living in coastal regions.The trend is expected to continue in both demographic indicators and urban development rate,being many coastal cities in seismic-and tsunami-prone regions and built through informal and unplanned settlements,exposing their population and assets to such hazards.Recent tectonic-triggered events raised awareness of the cascading earthquake and tsunami threat and highlighted the paucity of structural design criteria considering the cumulative effects of both.By being exposed to the ground-motion,the structures’resistance may decrease and become residual/non-existent to support the incoming tsunami,implying an underestimation of the risk.Risk management can benefit from reinforcing the ties between natural hazards and engineering practitioners,linking science and industry,and promoting dialogue between risk analysts and policy-makers.Motivated by the expansion plans of an internationally-sized deep-water port located in a tsunami-prone region,a reflection on the work needed to perform a multi-risk assessment and the challenges yet to overcome is introduced to emphasize the challenge of combining safety requirements with financial and ecologic concerns.A conceptual interdisciplinarybased methodology is proposed to support uncertainty-aware,systematic and informed decisions.展开更多
Large-scale floods induced by dam failures could cause significant structural damage to buildings and massive loss of life.The coupling effect of large-scale flood spread and building collapse has complex impacts on t...Large-scale floods induced by dam failures could cause significant structural damage to buildings and massive loss of life.The coupling effect of large-scale flood spread and building collapse has complex impacts on the entire flow field,affecting flood risk assessment and building vulnerability evaluation.In this paper,a dynamic elevation change model designed to seamlessly interface with a structural vulnerability assessment model to investigate the interaction effect between floods and buildings is presented.The efficiency of the framework was validated by reconstructing the Gleno Dam-Break flood in Italy.Subsequently,a hydrodynamic model of the Jinsha-Yalong River that considers dynamic building collapse was established.The proposed model was compared with two traditional building treatment approaches and one that ignored the buildings.The results show that the interaction between the flood and buildings decreases the low-velocity area(below 1 m/s)by 7.44%-9.56%while increasing the high velocity area(above 4 m/s)by 10.71%-11.96%.Traditional and neglecting building treatments provide preliminary insights into densely built areas,and the latter could be an alternative for simplification because it can represent the worst-case scenario.Building collapse in response to large-scale floods typically occurs in four stages:flood spread,rapid expansion,gradual expansion,and flood recession.This analysis offers novel perspectives on flood prediction and simulations where the floodplain may contain buildings.This method could be useful for assessing structural vulnerability associated with large building stocks and developing flood mitigation strategies in densely populated areas.展开更多
基金the National High Technology Research and Development Program (863) of China (No. 2006AA11Z209)
文摘The purpose of this paper is to identify the critical road sections and intersections in a road network which have great influence on the normal transport functions of the road network and to optimize the road network structure by reducing its vulnerability. In this paper, the framework of road network structural vulnerability measurement and improvement model is proposed. The network efficiency model is used to define road network structural vulnerability. Shanghai freeway network is analyzed based on this model. We find that using this model the critical components of the road network can be identified. Two methods which are increasing connections and rewiring are proposed to optimize the road network structural vulnerability and the results can be used to reduce the network vulnerability. The measurement method that we put forward for structure vulnerability is useful and important to optimize road network structure.
基金National Key Technology R＆D Program, No.2011BAK07B02, No.2008BAK50-05 National Natural Science Foundation of China, No,4117113 B
文摘The damage of dwelling houses constitutes the primary cause of casualties and asset loss in seismic disasters that occurred in Chinese rural areas. The structure of houses is crucial for assessing the vulnerability of rural houses. However, at present, available data on rural housing structure are incomplete and their spatial scales are inconsistent. This paper estimated the amount and ratio of rural houses in five structures, namely ＇wood＇, ＇brick＇, ＇mixed＇, ＇reinforced concrete＇, and ＇other＇, for 2380 counties across China. With the percent- age sampling census data in 2005, four accuracy levels were specified. Then, a set of down-scaling models were established, where the impact of climate, economic development level and ethnic minority cultural factors on rural housing structure, as well as the spatial autocorrelation of neighboring spatial units were considered. Based on the estimation results, a database of county-level rural housing structure was established, based on which the vul- nerability of rural houses in different areas was clarified.
基金supported by Fundacao para a Ciencia e Tecnologia,PhD grant no.SFRH/BD/137531/2018,ongoing at Lisbon University,Instituto Superior Tecnico,Civil Engineering Research and Innovation for Sustainability(CERIS)Lopes and Reis are grateful for the Foundation for Science and Technology’s support through funding UIDB/04625/2020 from the research unit CERIS+1 种基金finantial support by FEDER-Fundo Europeu de Desenvolvimento Regional,through COMPETE 2020-Programa Operacional Fatores de Competitividadethe National Funds through FCT-Fundacao para a Ciencia e Tecnologia,projects no.UID/FIS/04650/2019 and no.POCI-01-0145-FEDER-028118.
文摘The spatial distribution of the world population is uneven,with a density of about 40%living in coastal regions.The trend is expected to continue in both demographic indicators and urban development rate,being many coastal cities in seismic-and tsunami-prone regions and built through informal and unplanned settlements,exposing their population and assets to such hazards.Recent tectonic-triggered events raised awareness of the cascading earthquake and tsunami threat and highlighted the paucity of structural design criteria considering the cumulative effects of both.By being exposed to the ground-motion,the structures’resistance may decrease and become residual/non-existent to support the incoming tsunami,implying an underestimation of the risk.Risk management can benefit from reinforcing the ties between natural hazards and engineering practitioners,linking science and industry,and promoting dialogue between risk analysts and policy-makers.Motivated by the expansion plans of an internationally-sized deep-water port located in a tsunami-prone region,a reflection on the work needed to perform a multi-risk assessment and the challenges yet to overcome is introduced to emphasize the challenge of combining safety requirements with financial and ecologic concerns.A conceptual interdisciplinarybased methodology is proposed to support uncertainty-aware,systematic and informed decisions.
基金supported by the National Natural Science Foundation of China(Grant No.52192671)the National Key Research and Development Program of China(Grant No.2022YFC3090600)+1 种基金the Research Fund of the State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin(Grant No.SKL2022TS11)the Open Research Fund of Key Laboratory of River Basin Digital Twinning of Ministry of Water Resources(Grant No.Z0202042022)。
文摘Large-scale floods induced by dam failures could cause significant structural damage to buildings and massive loss of life.The coupling effect of large-scale flood spread and building collapse has complex impacts on the entire flow field,affecting flood risk assessment and building vulnerability evaluation.In this paper,a dynamic elevation change model designed to seamlessly interface with a structural vulnerability assessment model to investigate the interaction effect between floods and buildings is presented.The efficiency of the framework was validated by reconstructing the Gleno Dam-Break flood in Italy.Subsequently,a hydrodynamic model of the Jinsha-Yalong River that considers dynamic building collapse was established.The proposed model was compared with two traditional building treatment approaches and one that ignored the buildings.The results show that the interaction between the flood and buildings decreases the low-velocity area(below 1 m/s)by 7.44%-9.56%while increasing the high velocity area(above 4 m/s)by 10.71%-11.96%.Traditional and neglecting building treatments provide preliminary insights into densely built areas,and the latter could be an alternative for simplification because it can represent the worst-case scenario.Building collapse in response to large-scale floods typically occurs in four stages:flood spread,rapid expansion,gradual expansion,and flood recession.This analysis offers novel perspectives on flood prediction and simulations where the floodplain may contain buildings.This method could be useful for assessing structural vulnerability associated with large building stocks and developing flood mitigation strategies in densely populated areas.
