SCIENZA E BENI CULTURALI XXXII.2016
Carlo Blasi1, Giovanna Cacudi2, Antonella Di Marzo3, Mauro Matteini4 1 Consulente Specialista settore statico, Firenze, blasi.unipr@gmail.com 2 Sbeap province di Lecce, Brindisi e Taranto, Lecce, giovanna.cacudi@beniculturali.it 3 Sbeap province di Bari, BAT e Foggia, Bari, antonia.dimarzo@beniculturali.it 4 Consulente Specialista settore lapideo, Firenze, mmatteini@inwind.it
The recent restoration of the pediment in its structural and stone components was an opportunity for a critical reflection on the previous restoration of the 1980s. The perforations to insert armed bars, carried out in those years, for the structural consolidation and the use of ethyl silicate for the consolidation of the stone, widely diffused techniques at the time, have proven to be, in fact, the main cause of new phenomena of cracking and deterioration that have occurred after the restoration and, in particular, in May of 2011, with some fragments falling into the church parvis. The problems to be addressed, closely interconnected, were of two different natures: those related to the static reinforcement of the structure, affected by cracking phenomena consisting in lesions, cracks of the stone elements and joints, and the preservation of decorative elements, in turn affected by phenomena of surface disintegration (sugaring) of the stone. The contribution will explain in detail the action taken to resolve the critical issues induced by the previous restoration and to achieve a structural and stone consolidation congruent with the features of the monument. Only a critical reading and a methodological approach, both rigorous and multidisciplinary, can direct one to the correct solution of the complex problem of the restoration, also with the revival of substantially similar techniques to those of the past but with the use of appropriate materials and precautions. Experience has shown that solutions regarded as correct and adequate in literature and in common practice at the time of the first restoration, but still used in recent interventions of consolidation, have proven to be, over time, the primary source of new major damage.
Parole chiave/Key-words: Extraction of the armed bars, Lecce limestone consolidation, church of Santa Croce