DefinePK

Abstract

Ambient vibrations from microtremor measurement were carried out in the University Tun Hussein Onn Malaysia (UTHM) using Lennartz 1Hz tri-axial seismometer sensor. Microtremor measurements have been conducted on 5 boreholes at UTHM, to study the correlation between the natural frequency (Fo) and depth of borehole. All of ambient vibration has been analyzed using Horizontal to vertical spectral ratio (HVSR) method introduced by Nakamura (1989), where the natural frequencies of the site were estimated from the single peak of HVSR in the North-South (NS) and East-West (EW) directions. The reliability of natural frequency (Fo) values are distributed between 1.18 to 1.78 Hz in the both of the directions. Meanwhile, the soil thickness was calculated in the range between 34.13 to 37.90 m using by Eq. 1.