To highlight the importance of small earthquakes in seismic hazard, a study of the 11 May 2016, Mw 4.9, Tesistan, Mexico earthquake is presented. Due to the close proximity of the event to the city, accelerations were...To highlight the importance of small earthquakes in seismic hazard, a study of the 11 May 2016, Mw 4.9, Tesistan, Mexico earthquake is presented. Due to the close proximity of the event to the city, accelerations were considerably higher than those caused by historical severe earthquakes (6.0 < Mw < 8.2). This paper addresses two objectives related to the Tesistan event: the fi rst is to estimate the focal mechanism solution in order to place the event in the context of the tectonic environment of this area. The second is focused on a vulnerability evaluation of buildings that suff ered resonance. Several building′s typologies with variations in construction system and height are assessed in terms of resonance with the structural and soil periods. The results show that around the Zapopan station, strong damage is expected in intermediate to high-rise buildings (12-30 m) with moment resistant frame systems and in reinforced concrete shear walls. Masonry structures around this station may not present resonance. In contrast, in the surroundings of the Guadalajara station, all intermediate height buildings from 9 to 21 m may present resonance.展开更多
The horizontal to vertical spectral ratio(HVSR)methodology is used here to characterize pumice soils and to image the three-dimensional surface geometry of Guadalajara,Mexico.Similar to other Latin American cities,Gua...The horizontal to vertical spectral ratio(HVSR)methodology is used here to characterize pumice soils and to image the three-dimensional surface geometry of Guadalajara,Mexico.Similar to other Latin American cities,Guadalajara is exposed to high seismic risk,with the particularity of being the largest urban settlement in Latin America built on pumice soils.Methodology has not yet been tested to characterize subsoil depths in pumice sands.Due to the questionable use of traditional geotechnical tests for the analysis of pumice soils,HVSR provides an alternative for its characterization without altering its fragile and porous structure.In this work,resonance frequency(F0)and peak amplitude(A0)are used to constrain the depth of the major impedance contrast that represents the interface between bedrock and pumice soil.Results were compared with borehole depths and other available geotechnical and geophysical data and show good agreement.One of the profiles estimated on the riverbanks that cross the city,reveals different subsoil thickness that could have an impact on different site responses on riverine areas to an eventual earthquake.Government and academic efforts are combined in this work to characterize depth sediments,an important parameter that impacts the regulations for construction in the city.展开更多
文摘To highlight the importance of small earthquakes in seismic hazard, a study of the 11 May 2016, Mw 4.9, Tesistan, Mexico earthquake is presented. Due to the close proximity of the event to the city, accelerations were considerably higher than those caused by historical severe earthquakes (6.0 < Mw < 8.2). This paper addresses two objectives related to the Tesistan event: the fi rst is to estimate the focal mechanism solution in order to place the event in the context of the tectonic environment of this area. The second is focused on a vulnerability evaluation of buildings that suff ered resonance. Several building′s typologies with variations in construction system and height are assessed in terms of resonance with the structural and soil periods. The results show that around the Zapopan station, strong damage is expected in intermediate to high-rise buildings (12-30 m) with moment resistant frame systems and in reinforced concrete shear walls. Masonry structures around this station may not present resonance. In contrast, in the surroundings of the Guadalajara station, all intermediate height buildings from 9 to 21 m may present resonance.
基金Consejo Nacional de Ciencia y Tecnología of Mexico(CONACyT)under Grant No.1000473。
文摘The horizontal to vertical spectral ratio(HVSR)methodology is used here to characterize pumice soils and to image the three-dimensional surface geometry of Guadalajara,Mexico.Similar to other Latin American cities,Guadalajara is exposed to high seismic risk,with the particularity of being the largest urban settlement in Latin America built on pumice soils.Methodology has not yet been tested to characterize subsoil depths in pumice sands.Due to the questionable use of traditional geotechnical tests for the analysis of pumice soils,HVSR provides an alternative for its characterization without altering its fragile and porous structure.In this work,resonance frequency(F0)and peak amplitude(A0)are used to constrain the depth of the major impedance contrast that represents the interface between bedrock and pumice soil.Results were compared with borehole depths and other available geotechnical and geophysical data and show good agreement.One of the profiles estimated on the riverbanks that cross the city,reveals different subsoil thickness that could have an impact on different site responses on riverine areas to an eventual earthquake.Government and academic efforts are combined in this work to characterize depth sediments,an important parameter that impacts the regulations for construction in the city.
