During the recent earthquakes, the vertical component of the ground motion found to be exceeding the horizontal component, which directly contradicts the current codal provision that assumes the value of the vertical ground motion to be 1/2 to 2/3 of the horizontal component. Almost after every destructive earthquake engineers postulates that the structural damage such as elephant foot buckling...

Performance of structures during recent earthquakes shows that the effect of vertical component of earthquake (VCE) could be considered as one of the main causes of bridges collapse. In most of bridge design codes, for seismic analysis of bridges, VCE is not taken into account or a distinguished method isn’t presented for assessment of VCE. In the present work, the effect of VCE on two existing...

We investigated the validity of seismic site response characteristics estimated from microtremors by comparing them with those of earthquake motions. For this purpose we observed microtremors as well as earthquake motions using large (5-km diameter) and small (0.5-km diameter) arrays deployed on soft sediments. Specifically, we examined four estimates from microtremors: relative site amplificat...

ULF emission data at Lunping (epicentral distance, 120 km) have been analysed for the Chi-chi earthquake (with magnitude 7.6 and depth of 11 km) in Taiwan which occurred on 21 September 1999. Simple intensity analyses have not yielded any significant results but we have found, based on the analysis of polarization (the ratio of vertical magnetic field component Z to the horizontal component G),...

during the past decades, attempts have been made to develop an early warning system for coming destructive earthquakes a few seconds before the ongoing ground motion. in this paper, a practical method for the early warning of earthquakes in south iran is presented. this region is selected for study because it has high potential for generating earthquakes and has a more complete strong ground mo...

Field investigations and analyses of satellite images and aerial photographs reveal that the 2016 Mw 7.1 (Mj 7.3) Kumamoto earthquake produced a ∼40-km surface rupture zone striking NE-SW on central Kyushu Island, Japan. Coseismic surface ruptures were characterized by shear faults, extensional cracks, and mole tracks, which mostly occurred along the pre-existing NE-SW-striking Hinagu-Futagawa ...