Nisida, the memory of a myth

The island of Nisida is made up of a cluster of yellow tuff of volcanic origin, covered by a layer of inconsistent gray tuff mixed with pozzolan. This stratification originates underground cavities that, as for the city of Naples, cause the well-known heterogeneity of the subsurface. The presence of factories on the surface, often positioned in correspondence or in the vicinity of such irregularities, causes microcracks in the tuff, which tend to deteriorate over time, both for reasons related to flegreo bradyseism, both for propagation of cracking strengths phenomena. The island of Nisida is home to the juvenile Criminal Institute, housed in a building from the thirties of the last century, below which old Bourbon volumes are preserved, recently under excavation conducted by the current prison administration. To date, the morphology of these areas is not yet defined in terms of space, nor there is a clear functional relationship with the ancient Bourbon Laundry located along the ridge overlooking Porto Paone. The research in place includes two integrated phases. The first consists in an architectural and environmental relief operation, of the buildings interested by the recent excavation, and of the possible paths that marked the old infrastructural network of the island. The second consists in an assessment of the mechanical characteristics of the material constituent the isle and the artefacts, with the aim to determinate the staticity and integrity of the same, and of the load-bearing capacity as foundation rocks. The general objective of the research is the architectural and environmental safeguard of the island, and the assessment of the stability about the slope and the foundations of the buildings, including the Penitentiary Institute and the factories of the Bourbon period.