PSI - Issue 11

Giorgio Frunzio et al. / Procedia Structural Integrity 11 (2018) 153–160

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Prof. Ing. Giorgio Frunzio, Ing. Luciana Di Gennaro 00 (2018) 000–000

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1. Introduction: "il Palazzo Ducale di Parete"

The Palazzo Ducale di Parete is located in the historical centre of the homonymous District in the province of Caserta, next to the ancient parish church of San Pietro Apostolo. It borders on M. Basile street to the east, S. Africano street to the west, a private area to the south and Umberto I avenue. Palazzo Ducale is composed of a central nucleus (defensive tower), built probably between XI and XII century, and other blocks added in the following centuries. In particular, the palace, in its actual appearance, has a star shaped structure with four angular units shorter than the central tower and four other connecting units (of the same height) which represent the four principal fronts (Fig. 1b). Moreover, the building is made up of three levels on the ground beside a mezzanine and except for the central tower protrusion. Furthermore in the historical map of the feud of Parete (Fig 1a),dated back to the XVII cent. and shown at the offices of the District, the palace is clearly of a level shorter than the one now existing.

a

b

Fig. 1 – (a) Pianta del Feudo di Parete (XVII sec); (b) Groung Floor Plan

The whole structure is composed of grey tuff masonry of great quality made of squared blocks of average dimensions. The vertical load bearing masonries are of variable dimensions between 200 and 70 cm for the central defensive tower, and 100 and 60 cm for the structures of the palace. Over the years, they have undergone operations such as bed joint reinforcement, abolition of functional empty spaces and repayment injuries. The horizontal structures on the first level have been built with masonry crossvaults and barrel vaults, whereas the ones on the other levels have been made with wooden deckings. The original timber floors, consisted of a chestnut wood decking presumably made before 1700 made with a "primary frame" composed of wooden beams of an average diameter of 250 mm, placed at a wheelbase of about 1.00 m, and a "secondary frame" consisting of chestnut elements with semi-circular section, named panconcelle. These ones, placed orthogonally to the beams, are loosely connected to the main structure. Above the wood decking, was a lime-based concrete screed. Although the building was in a state of neglect at the time of restoration work, the beams was in good condition. the same cannot be said for the panconcelle that presented many rotting and degraded areas. For this reason, in order to know the real conditions of the wood, numerous control tests have been carried out as better described below. Being a historic monument of particular value, the restoration works have been carried out respecting the circular 26 of 2010 "Guidelines for the assessment and reduction of seismic risk of cultural heritage aligned with the new