Variabilidad de resultados de la exploración geofísica de sitios usando métodos de ondas superficiales
DOI:
https://doi.org/10.21703/0718-2813.2024.35.2796Palabras clave:
Métodos de Ondas Superficiales, Variabilidad, Dinámica de suelosResumen
Tras el terremoto del Maule 2010 (Mw 8.8), grandes cambios se produjeron en la normativa sísmica a nivel nacional. Uno de los aspectos interesantes fue el cambio en la metodología para la clasificación de suelos en la norma NCh433. En pocas palabras, se pasó del uso de parámetros de resistencia al uso de parámetros dinámicos del suelo, como el promedio armónico de la velocidad de propagación de ondas de corte en los 30 m superiores del terreno (Vs30) y el periodo predominante (Tg), que se evalúa incorporarlo. En este estudio, se comparan resultados obtenidos por 4 equipos de trabajo que exploran seis sitios utilizando diversos sensores, geometrías y procedimientos, todos ellos usando Métodos de Ondas Superficiales (MOS). Se observa que, en general, la estimación de Vs30 y Tg son bastante robustas, pero se encuentran importantes variaciones en los perfiles de velocidad obtenidos; es por ello que es necesario contrarestar el resultado con la estratigrafia del sondaje. Estos resultados reflejan las limitaciones y potencialidades de los MOS para estimar las propiedades dinámicas de sitios.
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