A Case History: Seismic Analysis of the Retaining Wall of the Sacro Convento in Assisi (Italy)

The aim of the present work is to analyse the seismic behaviour of the retaining wall of the square in front of the Basilica di San Francesco at Assisi that during a long seismic crisis occurred in September 1997 suffered some damage. Static, pseudo-static and dynamic analyses have been carried out on four significant sections of the wall. The data for the analysis derive from the geometric survey of the structures, the survey of the state of the damage, the measurement of the rotation movements of the wall, the collection of stratigraphic and geotechnical data, as well as the accelerometric recordings of the seismic events using instruments that had been in operation on the structures of the “Sacro Convento” since 1995. Built during the first half of the 16th century, the wall is made of stone masonry, is about 93 m long, 4 m thick, and supports an embankment, the height of which varies between 9.0 m and 12.5 m. The wall is approximately 18 m high, and is under the ground also in the front part; it has a rectangular transversal section in the lower part and a T-shaped section in the upper part. It is built on calcareous rock, and supports a covered portico that is about 3 5 m high. In practice, the recorded accelerometric history coincides with the one at the base of the wall. Numerous seismic events were recorded from 4/9/1997 to 6/10/1997, three of which had a PGA exceeding 0.15g. The most evident movement suffered by the wall was a rigid rotation that caused a movement at the top of the wall greater than 20 cm

Seismic microzonation: an essential tool for urban planning in seismic areas

Dramatic images of heaps of rubble produced in Italy by destructive earthquakes show the extreme vulnerability of urban systems and territory and the need for urgent measures to protect citizens, buildings, artistic heritage and landscape. According to this study, the reduction of vulnerability must go through ordinary city planning tools, prepared in time of seismic silence. They must be a strong reference point also for reconstruction. Therefore, a correct planning in seismic areas must be based on a deep knowledge of the territory, of its physical, historical and cultural characters. In this context, the studies of seismic microzonation have a central role in providing information about amplification phenomena linked to the interactions between seismic waves and soils and they are indispensable to manage an extraordinary event with ordinary urban planning instruments, as might be wished in an advanced nation

Seismic microzonation: an essential tool for urban planning in seismic areas

Dramatic images of heaps of rubble produced in Italy by destructive earthquakes show the extreme vulnerability of urban systems and territory and the need for urgent measures to protect citizens, buildings, artistic heritage and landscape. According to this study, the reduction of vulnerability must go through ordinary city planning tools, prepared in time of seismic silence. They must be a strong reference point also for reconstruction. Therefore, a correct planning in seismic areas must be based on a deep knowledge of the territory, of its physical, historical and cultural characters. In this context, the studies of seismic microzonation have a central role in providing information about amplification phenomena linked to the interactions between seismic waves and soils and they are indispensable to manage an extraordinary event with ordinary urban planning instruments, as might be wished in an advanced nation

Seismic microzonation: an essential tool for urban planning in seismic areas

Dramatic images of heaps of rubble produced in Italy by destructive earthquakes show the extreme vulnerability of urban systems and territory and the need for urgent measures to protect citizens, buildings, artistic heritage and landscape.According to this study, the reduction of vulnerability must go through ordinary city planning tools, prepared in time of seismic silence. They must be a strong reference point also for reconstruction.Therefore, a correct planning in seismic areas must be based on a deep knowledge of the territory, of its physical, historical and cultural characters.In this context, the studies of seismic microzonation have a central role in providing information about amplification phenomena linked to the interactions between seismic waves and soils and they are indispensable to manage an extraordinary event with ordinary urban planning instruments, as might be wished in an advanced nation

Earthquake Geotechnical Engineering Aspects of the 2012 Emilia-Romagna Earthquake (Italy)

On May 20, 2012 an earthquake of magnitude ML=5.9 struck the Emilia Romagna Region of Italy and a little portion of Lombardia Region. Successive earthquakes occurred on May 29, 2012 with ML=5.8 and ML=5.3. The earthquakes caused 27 deaths, of which 13 on industrial buildings. The damage was considerable. 12,000 buildings were severely damaged; big damages occurred also to monuments and cultural heritage of Italy, causing the collapse of 147 campaniles. The damage is estimated in about 5-6 billions of euro. To the damage caused to people and buildings, must be summed the indirect damage due to loss of industrial production and to the impossibility to operate for several months. The indirect damage could be bigger than the direct damage caused by the earthquake. The resilience of the damaged cities to the damage to the industrial buildings and the lifelines was good enough, because some industries built a smart campus to start again to operate in less of one month and structural and geotechnical guidelines were edited to start with the recovering the damage industrial buildings. In the paper a damage survey is presented and linked with the ground effects. Among these, soil amplification and liquefaction phenomena are analyzed, basing on the soil properties evaluation by field and laboratory tests. Particular emphasis is devoted to the damaged suffered by the industrial buildings and to the aspects of the remedial work linked with the shallow foundation inadequacy and to the liquefaction mitigation effects

Earthquake Geotechnical Engineering aspects: the 2012 Emilia-Romagna earthquake (Italy)

On May 20, 2012 an earthquake of magnitude ML=5.9 struck the Emilia Romagna Region of Italy and a little portion of Lombardia Region. Successive earthquakes occurred on May 29, 2012 with ML=5.8 and ML=5.3. The earthquakes caused 27 deaths, of which 13 on industrial buildings. The damage was considerable. 12,000 buildings were severely damaged; big damages occurred also to monuments and cultural heritage of Italy, causing the collapse of 147 campaniles. The damage is estimated in about 5-6 billions of euro. To the damage caused to people and buildings, must be summed the indirect damage due to loss of industrial production and to the impossibility to operate for several months. The indirect damage could be bigger than the direct damage caused by the earthquake. The resilience of the damaged cities to the damage to the industrial buildings and the lifelines was good enough, because some industries built a smart campus to start again to operate in less of one month and structural and geotechnical guidelines were edited to start with the recovering the damage industrial buildings. In the paper a damage survey is presented and linked with the ground effects. Among these, soil amplification and liquefaction phenomena are analyzed, basing on the soil properties evaluation by field and laboratory tests. Particular emphasis is devoted to the damaged suffered by the industrial buildings and to the aspects of the remedial work linked with the shallow foundation inadequacy and to the liquefaction mitigation effects