In some countries with seismicity,an adequate detection network is essential to assess seismic hazards.The Instituto Geografico Nacional(National Geographic Institute/IGN)of Spain manages a strong motion network distr...In some countries with seismicity,an adequate detection network is essential to assess seismic hazards.The Instituto Geografico Nacional(National Geographic Institute/IGN)of Spain manages a strong motion network distributed throughout the whole country and an earthquake detection network composed of velocity stations.This paper aims at studying the development of the strong motion network of the Spanish National Seismic Network(focusing on mainland Spain and the Balearics)in the last three decades.A Geographic Information System(GIS)has been implemented to integrate the attributes from the IGN’s database concerning the earthquake catalogue,seismograph and accelerometer networks,which enabled to analyse the data and map the distribution of detection equipments in the region.The irregularly distributed Spanish strong motion network was greatly expanded from 1990 to 2010.In the past decade,it developed at a slower rate,but more modern technology was implemented.展开更多
In this article, the fragility of reinforced concrete and steel structures in Bucharest, a city of high seismic hazard, designed using the recent building codes in Romania, is assessed. A total of 24 reinforced concre...In this article, the fragility of reinforced concrete and steel structures in Bucharest, a city of high seismic hazard, designed using the recent building codes in Romania, is assessed. A total of 24 reinforced concrete and steel structures with heights varying from five stories to 13 stories were analyzed. Their seismic fragility was evaluated using two procedures from the literature. In the first procedure(SPO2 FRAG), the fragility was derived based on the pushover curves using the SPO2 IDA algorithm, while in the second procedure(FRACAS), the fragility was derived from nonlinear time-history analyses. The analyzed structures were designed for three levels of peak ground accelerations, corresponding to mean return periods of 100,225, and 475 years. Subsequently, the damage assessment of the analyzed structures was performed using ground motions generated from a Monte-Carlo simulated earthquake catalogue for the Vrancea intermediate-depth seismic source. The damage degrees that were estimated using the SPO2 FRAG approach are higher than those estimated using the FRACAS approach. The life-cycle analysis of the structures shows that a further increase of the design peak ground acceleration for Bucharest is feasible from an economic point of view using the SPO2 FRAG results.However, based on the FRACAS results, the opposite conclusion can be drawn. Finally, generic lognormal fragility functions are proposed as a function of building height and structural system.展开更多
文摘In some countries with seismicity,an adequate detection network is essential to assess seismic hazards.The Instituto Geografico Nacional(National Geographic Institute/IGN)of Spain manages a strong motion network distributed throughout the whole country and an earthquake detection network composed of velocity stations.This paper aims at studying the development of the strong motion network of the Spanish National Seismic Network(focusing on mainland Spain and the Balearics)in the last three decades.A Geographic Information System(GIS)has been implemented to integrate the attributes from the IGN’s database concerning the earthquake catalogue,seismograph and accelerometer networks,which enabled to analyse the data and map the distribution of detection equipments in the region.The irregularly distributed Spanish strong motion network was greatly expanded from 1990 to 2010.In the past decade,it developed at a slower rate,but more modern technology was implemented.
文摘In this article, the fragility of reinforced concrete and steel structures in Bucharest, a city of high seismic hazard, designed using the recent building codes in Romania, is assessed. A total of 24 reinforced concrete and steel structures with heights varying from five stories to 13 stories were analyzed. Their seismic fragility was evaluated using two procedures from the literature. In the first procedure(SPO2 FRAG), the fragility was derived based on the pushover curves using the SPO2 IDA algorithm, while in the second procedure(FRACAS), the fragility was derived from nonlinear time-history analyses. The analyzed structures were designed for three levels of peak ground accelerations, corresponding to mean return periods of 100,225, and 475 years. Subsequently, the damage assessment of the analyzed structures was performed using ground motions generated from a Monte-Carlo simulated earthquake catalogue for the Vrancea intermediate-depth seismic source. The damage degrees that were estimated using the SPO2 FRAG approach are higher than those estimated using the FRACAS approach. The life-cycle analysis of the structures shows that a further increase of the design peak ground acceleration for Bucharest is feasible from an economic point of view using the SPO2 FRAG results.However, based on the FRACAS results, the opposite conclusion can be drawn. Finally, generic lognormal fragility functions are proposed as a function of building height and structural system.
