Subsoil seismic characterization through Vs30 for future structural assessment of buildings (Ciudad del Carmen, Mexico)

Abstract

<jats:p>Abstract. Although the seismic information from the subsoil is very important, in some areas of the world this is not available due to various factors, the main one being a seismically low area. It is important to say that the planet has been changing and many intraplate earthquakes have occurred in places never expected, spreading seismic waves to places where they were considered low seismicity. For example, on September 8, 2017 in Ciudad del Carmen, 500 km from the epicenter, the earthquake was felt causing damage to the facades of the buildings. Therefore, it is important to have the subsoil shear-waves velocities to subsequently generate a good analysis and structural seismic design. For this reason, in this study under the seismic approach an assessment of Ciudad del Carmen Campeche subsoil is presented. Active and passive Multichannel Analysis of Surface Waves and Refraction Microtremor technique to investigate seismically subsoil characteristics have been employed. Shear wave velocities were obtained up to a depth of 30 m with magnitudes of 172.45 m/s to 353.90 m/s. Based on the Vs30 values, the subsoil is seismically classified into D and E according to the criterion of the National Earthquake Hazards Reduction Program and International Building Code, turning out to be very vulnerable to high damage during the earthquake shaking. Furthermore, Ciudad del Carmen was regionalized into three types, where type I being a dense soil or averagely soft rock with Vs30 greater than 360 m/s, type II when the soil has an intermediate dynamic amplifications with Vs30 between 180 to 360 m/s, and type III correspond to a soil with large dynamic amplifications and Vs30 less than 180 m/s. </jats:p>