The Basilica of Collemaggio contains within itself a mix of different styles, the result of long and different construction phases and important recovery and restoration interventions to which the structure has been subjected over the centuries, due to the earthquakes that have devastated the capital of Abruzzo.
The criteria that guided the restoration projects of the Basilica were based on respect for the historical-artistic value of the monument and on the need to reconstruct the collapsed parts and repair the damaged ones, with the aim of recreating a unitary and coherent image of the monument and, at the same time, also obtaining a seismic improvement of its structural complex.
Furthermore, following the earthquake of April 2009, the façade remained unexpectedly intact, while its interior was seriously damaged: collapse of the transept and the central dome, serious lesions to the apses, widespread damage to the walls and collapse of the columns of the naves.
The restoration project of the Basilica, launched by the Municipality of L’Aquila and Eni with a memorandum of understanding signed in August 2012, proposed a wide-ranging model of collaboration, involving central and local institutions, universities and businesses.
The recovery process entrusted the planning, the management of the works and the safety coordination to the Superintendence of Architectural and Landscape Heritage for Abruzzo, then to the Superintendence of Archaeology, Fine Arts and Landscape for L’Aquila and Cratere, which coordinated the technical-scientific support activity guaranteed by the Polytechnic of Milan, the University La Sapienza of Rome and the University of L’Aquila.
Eni’s contribution, in addition to the financial component of the project, consisted in the activation of its organizational skills in complex projects, in the use of advanced technologies borrowed from its research and extraction activities in the energy sector and from the management capacity gained in the international competitive context in highly complex scenarios.
The restoration works involved the consolidation of the façade, the bell tower, the apse, all the walls and pillars of the nave (also with controlled dismantling techniques), the reconstruction of the collapsed part of the transept, the polylobed pillars, the triumphal arch and the roofs. The restoration also involved the flooring of the transept area, the marble balustrades, the frescoes and many other precious details of the Basilica.
The conservation, safety and seismic improvement of the Basilica were the main objectives of the restoration project: the structures were consolidated and the collapsed parts rebuilt using modern techniques and technologies, but compatible and respectful of the principles of protection of the historical-artistic and cultural values of the monument.
The transept suffered the greatest damage, with the total collapse of the large polylobed pillars, the triumphal arch and the roof. Finally, the pillars were entirely rebuilt, with an internal structure in reinforced concrete and recomposed stone facing.
The University of L’Aquila has also contributed in terms of research and consultancy regarding the aspects of the restoration of some structural elements of the Basilica, such as the masonry of the nave walls, the connection between the main façade and the nave walls and the bell tower.
For the most part, the use of traditional materials was foreseen, such as stainless steel for the tie rods and NHL natural hydraulic lime mortar for the injections, compatible with the existing construction and durable over time, but the use of more performing innovative materials was not overlooked, such as carbon fibre tapes or high-resistance galvanised steel fabrics.
