The microzonation of Fabriano – Dynamic geotechnical testing and seismic response analysis at Fabriano, Italy

 

The Umbria-Marche earthquake occurred in September-October 1997 caused serious structural damages in the town of Fabriano (Ancona, Italy), especially in two residential zones, Borgo and Serraloggia-La Spina, located respectively north-west and south-east of the alluvial valley along which the built-up area lies. In the two sites landslide deposits and eluvial-colluvial sediments of 10 to 15 mthickness are underlain by a bedrock consisting of bituminous marls of Gessoso-Solfifera formation.

 

The Umbria-Marche earthquake occurred in September-October 1997 caused serious structural damages in the town of Fabriano (Ancona, Italy), especially in two residential zones, Borgo and Serraloggia-La Spina, located respectively north-west and south-east of the alluvial valley along which the built-up area lies. In the two sites landslide deposits and eluvial-colluvial sediments of 10 to 15 mthickness are underlain by a bedrock consisting of bituminous marls of Gessoso-Solfifera formation.

To evidence the influence of local soil conditions on possible ground motion amplification, detailed geotechnical investigations and numerical one-dimensional ground response analyses were carried out in the two sites. In particular, boreholes with undisturbed sampling, in laboratory geotechnical tests for measuring static and dynamic soil properties, and field geophysical tests to evaluate low-strain soil stiffness, were performed. Two time history accelerations, with a peak ground acceleration of 0.2g, were assumed as reference motions on rock in the numerical modelling. They were obtained by a probabilistic-statistical seismic hazard analysis carried out in terms of response spectrum ordinates. Further ground response analyses were performed, assuming as input motions the two time history accelerations scaled to a peak value of 0.1 g, which was approximately the amplitude of the ground surface peak horizontal acceleration on stiff soil at Fabriano produced by the main shocks of the 1997 earthquake.

The results of the static and dynamic soil property measurements and of the ground response analyses carried out at the two sites with the four above mentioned time history accelerations are presented in this paper.


  The Umbr …


AUTORI: Crespellani T., Ciulli B., Madiai C., Vannucchi G.
RIG ANNO:2000 NUMERO:2
Numero di pagine: 146


Allegato: https://associazionegeotecnica.it/wp-content/uploads/2010/03/RIG_2001_2_146.pdf
Allegato:
Articolo completo: https://associazionegeotecnica.it/wp-content/uploads/2010/03/RIG_2001_2_146.pdf