Bell tower – Avellino

General project description

The bell tower, owned by the Archconfraternity, had a number of structural issues prior to the works, typical of historic masonry buildings:

• vulnerability to seismic activity,
• inconsistencies in the materials,
• amplification of vibrations at the first modal frequency, which is particularly critical for tall, slender structures.

The project involved seismic retrofitting, with the stated aim of increasing the IS-V safety index by at least 10 per cent, without altering the character of the building or resorting to invasive solutions incompatible with its historic value.
ISAAC was approached directly by the lead designers on the project, Engineers Loffa and Amura. From the outset, a close and open relationship was established, based on the shared objective of combining safety, respect for the historic building and sustainability of the renovation.

Why ISAAC

The decision to use ISAAC technology proved to be crucial: in a listed historic building, where any intervention must be reversible, clearly identifiable and in compatible with its architectural integrity, the ISAAC system makes it possible to control vibrations and reduce seismic response without altering the building’s historic fabric or detracting from its appearance.

Working with the system designers was crucial: together we tackled both practical challenges – linked to the limited space – and theoretical challenges, developing FEM models capable of estimating the structure’s response following the intervention. The expected result is an overall seismic improvement of around 40 per cent – well above the 10 per cent required by the client – achieved without any invasive work on the historic structure, as the installation involved only the internal core built in the 1990s,” commented the engineers Amura and Loffa, who oversaw the project on behalf of the client.