Abstract

In this work, the fundamental period of the soil (Tf) was identified in 185 sites located in the Central Canton of San José (CCSJ), by using the H/V spectral ratio. The fundamental periods were obtained from measurements at each site. About 85 % of the sites where the H/V method was applied allowed a clear identification of the fundamental period, which corresponds to the peak of the highest amplitude in the H/V graph. When presenting the results of Tf in maps, 3 zones are clearly observed, where the periods are on average 0.5 s with extreme values of 0.1 to 0.9 s for zone 1, less than 0.3 s for zone 2 and variable between 0.1 and 0.4 s for zone 3. The highest measured fundamental period is located as an isolated point in the southwestern sector of the Mata Redonda district and has a value greater than 0.8 s. Both the soil classification and the Vs30 parameter were estimated from correlations established by Pinzón et al. (2021).

Keywords: soil fundamental period; Vs30; site classification; San Jose