Paesaggio Urbano 02.2013 | Page 48

TEssutO URBANo · URBAN Fabric Edifici in aggregato nella zona rossa di Concordia sulla Secchia, Modena Buildings in stock in the red zone of Concordia on the Secchia, Modena The current layout of urban centres is a dense web of buildings one on top of the other and mutually dependent. The result is an extremely heterogeneous fabric, about which not much is known in terms of size, geometry, construction, energy and occupational characteristics, etc. The land registry services keep detailed surveys on the property units: totally unconnected data, which do not allow immediate projections to be 46 paesaggio urbano 2.2013 obtained on the composition of a historic centre. Satellite images and virtual navigation services offer support in the understanding of grouped building fabric which remains, however, superficial. The earthquakes have highlighted the fragility of historic centres, not only from a structural point of view, but also from a knowledge and management point of view. Whereas on the one hand the study of geological phenomena, like the understanding of the behaviour of masonry structures, has achieved remarkable results, the application of any kind of calculation model or intervention programme must deal with the unknown of the grouped fabric. When the assessment of the damage is followed by the need for the administrations to coordinate the redevelopment works (and relative funding), a thorough knowledge of the structural units that constitute the groups of buildings is essential. Before being drawn up, the Reconstruction Plans require the recognition of the U.M.I. (Minimum Intervention Units): independent buildings and structural units in building groupings […] that are made up of more than one building whose repair, restoration with seismic improvement or reconstruction must be designed individually, to be implemented through a single building intervention, or through a programme of interventions split into different stages or lots. The recognition of the U.M.I.s must consider the typological, architectural and landscape characteristics of the building fabric, whereas the planning requirements impose the choice of recalculating the envisaged sections of work, on the one hand fulfilling the need to effectively organise the reconstruction operations, but at the same time cancelling out the advantages of a legitimate enquiry operation into the urban event.