hrvatski

BUILDING DAMAGE CAUSED BY THE ML5.5 ZAGREB EARTHQUAKE OF MARCH 22, 2020

This paper presents observed damage to buildings, caused by the earthquake that occurred in March, 2020 in Zagreb, Croatia, and gives an overview of the main causes of damage and typical failure mechanisms. The epicenter was within the city, less than 7 km from the historic center and at shallow depth of 8 km. The mainshock was of the magnitude ML5.5, while the strongest aftershock was ML4.9 and occurred 40 minutes after the mainshock, followed by a long-term seismic activity. These events caused a loss of one life, 26 injured and extensive damage to many buildings, including important infrastructural buildings, such as hospitals and schools. Many cultural heritage buildings of great interestwere also severely damaged. Damage occurred mainly due to a fact that about two third of all residential units in Zagreb were built before 1964, when the first seismic code was introduced in the region. The residential building stock in the center of the city comprising unreinforced masonry buildings, dating back to the 19th century and the beginning of the 20th century, sustained significant damage. Many chimneys and other unrestrained elements collapsed, many gable walls overturned, and load-bearing walls of some buildings were severely damaged. On the other hand, most of the newer buildings were not damaged, except for some single-family houses in the epicentral region and those buildings that had significant construction errors. In this paper, typical damage of unreinforced masonry buildings is presented. Finally, conclusions on the masonry building vulnerability and main causes of damage that have been identified are drawn, in order to mitigate the earthquake risk in the future.

masonry buildings ; damage ; historic center ; ductility ; failure mechanisms

nije evidentirano

njemački

BUILDING DAMAGE CAUSED BY THE ML5.5 ZAGREB EARTHQUAKE OF MARCH 22, 2020

This paper presents observed damage to buildings, caused by the earthquake that occurred in March, 2020 in Zagreb, Croatia, and gives an overview of the main causes of damage and typical failure mechanisms. The epicenter was within the city, less than 7 km from the historic center and at shallow depth of 8 km. The mainshock was of the magnitude ML5.5, while the strongest aftershock was ML4.9 and occurred 40 minutes after the mainshock, followed by a long-term seismic activity. These events caused a loss of one life, 26 injured and extensive damage to many buildings, including important infrastructural buildings, such as hospitals and schools. Many cultural heritage buildings of great interestwere also severely damaged. Damage occurred mainly due to a fact that about two third of all residential units in Zagreb were built before 1964, when the first seismic code was introduced in the region. The residential building stock in the center of the city comprising unreinforced masonry buildings, dating back to the 19th century and the beginning of the 20th century, sustained significant damage. Many chimneys and other unrestrained elements collapsed, many gable walls overturned, and load-bearing walls of some buildings were severely damaged. On the other hand, most of the newer buildings were not damaged, except for some single-family houses in the epicentral region and those buildings that had significant construction errors. In this paper, typical damage of unreinforced masonry buildings is presented. Finally, conclusions on the masonry building vulnerability and main causes of damage that have been identified are drawn, in order to mitigate the earthquake risk in the future.

masonry buildings ; damage ; historic center ; ductility ; failure mechanisms

nije evidentirano