Abstract :
This contribution expounds the operational plan structured to acquire digitally the data relative to the integrated survey activity in the municipalities of Brittoli, Bussi sul Tirino, Civitella Casanova, Cugnoli, Montebello di Bertona, Popoli and Ofena, that are set in the seismic crater of Abruzzo. The strong earthquake that on 6 April 2009 devastated the city of L\´Aquila radiating in an area of about three thousand square kilometres and affecting, to various degrees, more than 57 municipalities in Abruzzo, provides an immediate idea on the extent of the damage, the analytical and planning difficulties related to various organizational stages of the reconstruction. This is where the dutiful commitment of the University of Abruzzo derives from, the research conducted in these years by the working group of Pescara at the places hit by the earthquake. Firstly, it m ust be specified that the so-called "seismic crater" has been divided into n ine homogeneous areas. Our research unit occupies of the N 05 homogeneous area, extending between the valley of the river Pescara and the foothills of the eastern side, adjacent to the two National Parks of the Gran Sasso and Monti della Laga, and Velino Sirente. With the support network and topographic survey, the definition of the absolute reference system was realized, which was obtained through the identification of 4 reference points, defined with topographic nails and appropriately positioned in respect to the perimeter of the study areas individuated in the single historic centres. The calculation made with GPS helped us to o btain the vertices of densification, attributed to the IGM95 network of Abruzzo region. These were the preparatory procedures for the geo-referencing o f the settlement and for a subsequent scanning carried out with Laser instruments. On the basis of the principal topographic polygonal lines the secondary ones were defined, inside the settlements, and arranged in a way to be crossed longit- dinally and transversely. The internal reference grids were realized according to the scheme of the closed polygon rings, so we tried to create a single, large ring that surrounds the confined zone to b e pointed out, criss-crossed by linking the opposite extremes. At the same time the targets, the points of connection were fixed and at this early stage they were detected with topographic instruments and then got relinked with a 3D laser scanner in order to geo-reference the point clouds. The detection of the areas included within the delimitations, at this stage, required the acquisition of photographic documentation, organized in two phases. The first is referable to the indicated image shooting, carried out with the aim to document the damage immediately after the earthquake and to monitor the initial state and the following interventions. The second and more detailed one, with the aim to control the metric data and to provide a preliminary feedback between the photographic and measured information. The surveying, carried out with total station, covered the detailed survey of the facades and individual building elements for the definition and placement of the joint to the ground and, off the ground, of the previously affixed topographic targets. The sketches and the reference monographs correspond to the detection of the single points, which are numbered and shown in charts. For motives of optimization of the measurement system, it was decided to proceed in blocks, giving priority to main roads and areas identified by the " Pilot Projects". The materials collected during the enterprise of photographic documentation, were partly used to make image rectifications of facades. It has to be said that in many cases for the small road sections, typical of the historical centres, it was not always possible to realize the appropriate photo rectifications, balanced, in these situations with the aid of ortho-photos, obtained by the restitution of point clouds, acquired wit
