Damage and Vulnerability Assessment of Churches after the 2002 Molise, Italy, Earthquake

Abstract

The 2002 Molise, Italy, earthquake sequence shocked the Italian public because it killed school children, but it also highlighted the fact that seismic vulnerability of historic masonry buildings has increased because of reinforcement work that has been done in the last 50 years. Replacing the original wooden roof structure with new reinforced concrete or steel elements, inserting reinforced concrete tie-beams in the masonry and new reinforced concrete floors, and using reinforced concrete jacketing on the shear walls are all widely used interventions. However, they lead to increased seismic force (because of greater weight) and to deformations incompatible with the masonry walls. The authors present results of an extensive survey of damage resulting from recent Italian seismic events (with particular reference to the Molise earthquake). We evaluate the effectiveness and applicability of some retrofitting methods in the hope that these findings will be taken into account in technical codes.

Damage assessment of churches after L’Aquila earthquake (2009)

“…Studies done on churches, starting from the observation of damage after the Friuli earthquake in 1976 (Doglioni et al 1994) and more systematically after the earthquakes in Umbria and the Marches in 1997 (Lagomarsino and Podestà 2004a) and Molise in 2002 (Lagomarsino and Podestà 2004c), have demonstrated that damage mechanisms in churches have certain recurring characteristics, notwithstanding the uniqueness of each site. In particular, the interpretation using macro elements has proven very useful, i.e.…”

“…In particular, the church form considers 28 damage and collapse mechanisms that can frequently occur in the different architectonic elements (named macroelements) which compose churches (Lagomarsino and Podestà 2004c). Table 1 shows the mechanisms considered and the related macroelement.…”

Statistical Assessment of Damage to Churches Affected by the 2010–2011 Canterbury (New Zealand) Earthquake Sequence

“…By filling in all the other sections Downloaded by [George Washington University] at 04:26 08 February 2015 of the form, it is possible to register information about the church itself, general damage, and seismic vulnerability, and to assist decisions about the viability and detailing of temporary propping and other safety measures [Costa, 2009;Grimaz, 2011]. It is also possible to estimate the cost of the required structural interventions using an economic loss model, based on the damage level in each macroelement [Lagomarsino and Podestà, 2004b].…”

“…According to Civil Protection Department [2006], inspectors are expected to identify possible collapse mechanisms from a list on the form and then grade the activated mechanisms within a scale [Grunthal et al, 1998]: 1-Negligible to slight damage; 2-Moderate damage; 3-Substantial to heavy damage; 4-Very heavy damage; 5-Destruction. The first version of the form had 18 possible collapse mechanisms [Angeletti et al, 1997] and was used to assess almost 3,000 churches in Umbria-Marché, Italy, after the earthquake of September 26, 1997 [Lagomarsino and Podestà, 2004a] and in Molise, Italy, after the earthquake on October 31, 2002 [Lagomarsino and Podestà, 2004b]. The form was also applied in the Azores, Portugal, after the earthquake on July 9, 1998 [Guerreiro et al, 2000].…”

Diagnostic strategies for the repair intervention on churches damaged by earthquakes: the Toscolano Maderno Monumental Complex

“…The experience in seismic areas showed that this type of buildings is subjected to typical and repetitive damage mechanisms (Doglioni [5], Lagomarsino [6]), as: the façade overturning, the in plane damage of the lateral walls, the damage of the apse and of the bell tower, etc.…”