The parameters of the bridge's resistance to dynamic loads, such as natural frequency and damping ratio, were determined by theoretical experimental modal analysis. Microtremor measurements performed on two types bridges: steel truss bridges reinforced concrete bridges. goal is establish value characteristics well feasibility based SNI 2833-2008's vibration period limit. test used compare frequ...

Abstract The 7.5 M w tectonic earthquake that hit Palu City on 28 September 2018 was followed by tsunami and liquefaction, triggered massive mudflows in Balaroa, Petobo, Jono Oge areas. This study focuses the generating factors of liquefaction such as condition soil lithology, depth water table, distance to focal mechanism, thickness soft sediment. Microtremor data, including Horizontal Vertica...

Recently, the use of microtremor techniques for subsoil investigation has increased significantly. The HVSR (Horizontal to Vertical Spectral Ratio) technique allows, in many cases, obtain a seismo-stratigraphic reconstruction and identify areas with similar seismic behavior. However, stratigraphic interpretation peaks still remains subjective choice linked priori information. A non-hierarchical...

Abstract Microtremor is recorded with a device that very sensitive to subsurface soil vibrations, unwanted noise frequency waves are often also included. For this reason, processing needs be done using filters can attenuate the noise. In previous research, signal decomposition was performed Interpolated Finite Impulse Response (IFIR) filter and resulted attenuation at desired value. Using MATLA...

A set of horizontal to vertical spectral ratio (HVSR) and multichannel analysis of surface waves (MASW) measurements, carried out in the Altavilla Milicia (Sicily) area, is analyzed to test a geological model of the area. Statistical techniques have been used in different stages of the data analysis, to optimize the reliability of the information extracted from geophysical measurements. In part...

The use of horizontal to vertical spectral ratios (HVSR) earthquake ground motions has become a standard technique characterize sites, especially those lacking subsurface measurements. Several studies have developed relationships between HVSR results and time-averaged shear-wave velocity in the upper 30 m (VS30). Other utilized calculated from motion Fourier amplitude spectra estimate VS30. Anc...

Geophysical techniques were employed to analyze one of the landslides that affected main access road Pujilí (Ecuador). A passive seismic technique was utilized test a total 70 horizontal vertical spectral ratio (HVSR) points, complemented by an active seismic-refraction profile and multichannel analysis surface waves (MASW) survey. The results from geophysical surveys facilitated determination ...