Introduction With rapid development and advancement of economy and society, lots of city groups or city belts with ex-tra-large cities as their centers have been formed in China. The regions these city groups lie i...Introduction With rapid development and advancement of economy and society, lots of city groups or city belts with ex-tra-large cities as their centers have been formed in China. The regions these city groups lie in usually havewell-developed economy, dense population, and are regional politics and culture centers. Some groups lie in theregions with high level of earthquake activity, such as the Surrounding Capital City Group with the centers of Bei-jing and Tianjin. Once a large earthquake occurs, its influence will spread to very extensive region and its disasterwill be tremendous too. So earthquake resistance and disaster mitigation of city group will be very significant issue.The cities in a group have close distance with each other; they can carry out unified preparation for disaster as onewhole and reduce the heavy load of single city before an earthquake, and have an advantage of prompt mutual-aidafter an earthquake because of close distance. It is especially significant to mitigate the lose of lives. One importantprecondition is that all the cities in one group cannot be exposed to the same level of destroy during one earth-quake. So the division of city group in the region with dense cities distribution shall be very significant to theemergent mutual-aid in early time after a large earthquake. For this goal, the characteristics and correlativity ofearthquake′s impact on cities in one group need to clearly be considered. The cities with similar features and strongcorrelativity of historical earthquake influence have large chance to suffer same level destroy during the futurestrong earthquake and are disadvantage to provide mutual-aid and shall not be divided into one group. ……展开更多
The tunnel industry has considered that tunnels,especially tunnels in rock,are naturally resistant to earthquake action,including faulting,shaking,deflection and ground failure.As the number of case histories of tunne...The tunnel industry has considered that tunnels,especially tunnels in rock,are naturally resistant to earthquake action,including faulting,shaking,deflection and ground failure.As the number of case histories of tunnels subject to earthquake action has increased,the industry has started to recognize that,although tunnels in rock have good resistance against earthquakes generating peak ground accelerations(PGA)lower than 0.5 g,it is important to include the dynamic forces and displacements generated by seismic ground motions in the design process to obtain a more reliable design.These additional earthquake forces impact the final design,potentially requiring changes to the ground support and additional reinforcement of the concrete lining,as illustrated by case histories presented in this paper.展开更多
The 16 April 2016 earthquake in Ecuador exposed the significant weaknesses concerning the methodological designs to compute—from an economic standpoint—the consequences of a natural hazard-related disaster for produ...The 16 April 2016 earthquake in Ecuador exposed the significant weaknesses concerning the methodological designs to compute—from an economic standpoint—the consequences of a natural hazard-related disaster for productive exchanges and the accumulation of capital in Ecuador.This study addressed one of these challenges with an innovative ex ante model to measure the partial and net short-term effects of a natural hazard-related catastrophe from an interregional perspective,with the 16 April 2016 earthquake serving as a case study.In general,the specified and estimated model follows the approach of the extended Miyazawa model,which endogenizes consumption demand in a standard input–output model with the subnational interrelations and resulting multipliers.Due to the country’s limitations in its regional account records the input–output matrices for each province of Ecuador had to be estimated,which then allowed transactions carried out between any two sectors within or outside a given province to be identified by means of the RAS method.The estimations provide evidence that the net short-term impact on the national accounts was not significant,and under some of the simulated scenarios,based on the official information with respect to earthquake management,the impact may even have had a positive effect on the growth of the national product during 2016.展开更多
文摘Introduction With rapid development and advancement of economy and society, lots of city groups or city belts with ex-tra-large cities as their centers have been formed in China. The regions these city groups lie in usually havewell-developed economy, dense population, and are regional politics and culture centers. Some groups lie in theregions with high level of earthquake activity, such as the Surrounding Capital City Group with the centers of Bei-jing and Tianjin. Once a large earthquake occurs, its influence will spread to very extensive region and its disasterwill be tremendous too. So earthquake resistance and disaster mitigation of city group will be very significant issue.The cities in a group have close distance with each other; they can carry out unified preparation for disaster as onewhole and reduce the heavy load of single city before an earthquake, and have an advantage of prompt mutual-aidafter an earthquake because of close distance. It is especially significant to mitigate the lose of lives. One importantprecondition is that all the cities in one group cannot be exposed to the same level of destroy during one earth-quake. So the division of city group in the region with dense cities distribution shall be very significant to theemergent mutual-aid in early time after a large earthquake. For this goal, the characteristics and correlativity ofearthquake′s impact on cities in one group need to clearly be considered. The cities with similar features and strongcorrelativity of historical earthquake influence have large chance to suffer same level destroy during the futurestrong earthquake and are disadvantage to provide mutual-aid and shall not be divided into one group. ……
文摘The tunnel industry has considered that tunnels,especially tunnels in rock,are naturally resistant to earthquake action,including faulting,shaking,deflection and ground failure.As the number of case histories of tunnels subject to earthquake action has increased,the industry has started to recognize that,although tunnels in rock have good resistance against earthquakes generating peak ground accelerations(PGA)lower than 0.5 g,it is important to include the dynamic forces and displacements generated by seismic ground motions in the design process to obtain a more reliable design.These additional earthquake forces impact the final design,potentially requiring changes to the ground support and additional reinforcement of the concrete lining,as illustrated by case histories presented in this paper.
文摘The 16 April 2016 earthquake in Ecuador exposed the significant weaknesses concerning the methodological designs to compute—from an economic standpoint—the consequences of a natural hazard-related disaster for productive exchanges and the accumulation of capital in Ecuador.This study addressed one of these challenges with an innovative ex ante model to measure the partial and net short-term effects of a natural hazard-related catastrophe from an interregional perspective,with the 16 April 2016 earthquake serving as a case study.In general,the specified and estimated model follows the approach of the extended Miyazawa model,which endogenizes consumption demand in a standard input–output model with the subnational interrelations and resulting multipliers.Due to the country’s limitations in its regional account records the input–output matrices for each province of Ecuador had to be estimated,which then allowed transactions carried out between any two sectors within or outside a given province to be identified by means of the RAS method.The estimations provide evidence that the net short-term impact on the national accounts was not significant,and under some of the simulated scenarios,based on the official information with respect to earthquake management,the impact may even have had a positive effect on the growth of the national product during 2016.