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The Latin Colony (303 BC) of Alba Fucens (L’Aquila, Italy) is the largest archaeological area of the whole Apennines. Due to its extension, location and environmental context, the conservation of the site is particularly complex.For these reasons, in the paper a multiscale and multidisciplinary geoarchaeological study (remote sensing and UAV photogrammetry) of the site, to extract and measure morphostructural information to be associated to the environmental context, risk assessment and conservation, is reported.The study area is located on a higher geostructure with a subangular shape, which suggests a tectonic origin, with respect to the surrounding plain and bounded to the East by a large fan that takes place towards the Piana del Fucino.First, the geo-structural analysis, using the Landsat-8 and GeoEye multispectral sensors, was performed. The GeoEye satellite image allowed carrying out the morphological analysis of the archaeological area, its physical characteristics, the drainage pattern and the land use. Subsequently, after image processing of satellite data, a UAV survey was carried out in some relevant zones. Considering the UAV photogrammetry accuracy information, it was possible to extract data as map producing with several advantages (economic and time saving, minimum field work). With a multiscale and metric approach, the geomatics techniques allowed to deeply investigate some areas, creating detailed 3D models for evaluate risks and the decay. Finally, a general discussion about risk mitigation and conservation is reported.

Monitoring infrastructures is becoming an important and challenging issue. In Italy, the heritage consists of more than 60,000 bridges, which need to be inspected and detected in order to guarantee their strength and durability function during nominal lifespan. In this paper, a non-destructive survey methodology for study concrete bridges surface deterioration and viaducts is presented. Terrestrial and unmanned aerial vehicle (UAV) photogrammetry has been used for visual inspection of a standard concrete overpass in L’Aquila (Italy). The obtained orthomosaic has been processed by means of Object-Based Image Analysis (OBIA) to identify and classify deteriorated areas and decay forms. The results show a satisfactory identification and survey of deteriorated areas. It has also been possible to quantify metric information, such as width and length of cracks and extension of weathered areas. This allows to perform easy and fast periodic inspections over time in order to evaluate the evolution of deterioration and plan urgency of preservation or maintenance measures.

“Is beach erosion a natural cycle or is it getting worse with rising sea levels [...]

Nowadays geomatic techniques can guarantee not only a precise and accurate survey for the documentation of our historical heritage but also a solution to monitor its behaviour over time after, for example, a catastrophic event (earthquakes, landslides, ecc). Europe is trying to move towards harmonized actions to store information on cultural heritage (MIBAC with the ICCS forms, English heritage with the MIDAS scheme, etc) but it would be important to provide standardized methods in order to perform measuring operations to collect certified metric data. The final result could be a database to support the entire management of the cultural heritage and also a checklist of “what to do” and “when to do it”. The wide range of geomatic techniques provides many solutions to acquire, to organize and to manage data at a multiscale level: high resolution satellite images can provide information in a short time during the “early emergency” while UAV photogrammetry and laser scanning can provide digital high resolution 3D models of buildings, ortophotos of roofs and facades and so on. This paper presents some multiscale survey case studies using UAV photogrammetry: from a minor historical village (Aielli) to the centre of L’Aquila (Santa Maria di Collemaggio Church) from the post-emergency to now. This choice has been taken not only to present how geomatics is an effective science for modelling but also to present a complete and reliable way to perform conservation and/or restoration through precise monitoring techniques, as shown in the third case study.

This paper represents the result of the IAEG C35 Commission “Monitoring methods and approaches in engineering geology applications” workgroup aimed to describe a general overview of unmanned aerial vehicles (UAVs) and their potentiality in several engineering geology applications. The use of UAV has progressively increased in the last decade and nowadays started to be considered a standard research instrument for the acquisition of images and other information on demand over an area of interest. UAV represents a cheap and fast solution for the on-demand acquisition of detailed images of an area of interest and the creation of detailed 3D models and orthophoto. The use of these systems required a good background of data processing and a good drone pilot ability for the management of the flight mission in particular in a complex environment.

The archaeological site of Alba Fucens (L’Aquila, Italy) (303 BC) is the largest archaeological area of the whole Apennines. Extension, location and environmental context of the site require new methods for risk mitigation and conservation. In this paper, a multiscale geomatic approach, based on remote sensing and UAV photogrammetry, is reported. The main purpose is the extraction of architectonic and weathering information, useful for a better fruition and conservation. For a multiscale approach, very high resolution satellite images (WorldView2) and UAV Photogrammetry technique have been used. The satellite image processing, performed by Normalized Difference Vegetation Index (NDVI), High-pass filter, Principal Component Analysis (PCA) and classification, allowed to detect buried or emerging structures and to estimate fire and erosion risks. On the other hand, UAV photogrammetry technique allowed to evaluate detailed architectural information of the buried (ima, media and summa caveae) and excavated amphitheatre structures (arena, podium and steps). Furthermore it was also possible to systematically acquire complete and reproducible data on stone materials (limestones) and their weathering (loss of stone material, natural or anthropogenic break out, deposits, efflorescences, dark or light crusts, biological colonization, granular and crumbly disintegration, flaking and fissures). With a multiscale and metric approach, the geomatic techniques allow to deeply investigate the monument-mapping and to create a detailed 3D models. In this way, the stone decay, the risks and their mechanisms can be evaluated, in order to plan and perform future actions and interventions for their mitigation.

This paper describes the application of some new mathematical algorithms, developed at Semeion Research Center and based on Artificial Adaptive System (AAS), to the redundant measurements of displacement of an extremely-slow landslide that may be affected by some systematic errors. The main aim is to understand if AAS may overcome their influence in the definition of the landslide kinematic behavior thus being able to use the measurements even though they differ by systematic errors. This would be a particularly good result for the monitoring of extremely-slow landslides that move at displacement rates less than 16 mm/year and can be recognized only with instrumentation, usually of geodetic type for the ground surface and inclinometers for the subsurface. In the short time, displacements are so small that they may include systematic errors of the same order of magnitude that can neither be identified nor reduced. For the monitoring of extremely-slow landslides it is therefore recommended to use redundant measurement systems and check the reliability of data by comparing the displacements. This paper shows how the use of the Artificial Adaptive System may get the information on the landslide kinematic even when there is no agreement between displacements measured with the different techniques. The validation of these results was made by comparing them with the well-known data field and a good agreement was found.

In the last decades the photogrammetry has undergone interesting innovation, both in terms of data processing and acquisition mode, to allow obtaining detailed 3D models useful for complete survey and important support for the management and recovery of cultural heritage and buildings. However, despite recent developments, the main photogrammetry outputs are raster data (ortophoto and DEM) and point clouds characterized by high informative content, but they are not typically extracted automatically. Automated feature detection is yet manual, time-consuming procedure and an active area of research. The raster to vector conversion is not direct, but transformations must be performed on the input data to convert the pixel values into features. Always, segmentations are preceded by filter technique to remove noise and to improve the conversion phase. However, remote sensing data and especially UAV photogrammetry output are the most complex to treat because of their heterogeneity (presence of different objects and shapes), the nature of sensor used and the different scale. In this work we experiment new enhancement filter to improve the automatic extraction of vector information for a UAV photogrammetry results of the facing walls of eminent church, symbol of the city of L’Aquila, the” Basilica of Santa Maria di Collemaggio”.

This paper illustrates an innovative methodology for post-earthquake collapsed building recognition, based on satellite-image classification methodologies and height variation information. Together, the techniques create a robust classification that seems to yield good results in this application field. In the first part of this study, two different feature extraction methodologies were compared, based respectively on pixel-based and object-oriented approaches. Then the classification results of the most accurate classification methodology. obtained on an eight band WorldView-2 monoscopic image, were completed with height variation information before and after the event. The height difference is calculated, comparing a photogrammetric DSM, obtained using a photogrammetric rigorous orbital model on some EROS-B 0.7 metre across-track stereopairs with a ‘roof model’ before the earthquake.

On April 6, 2009, an earthquake of 6.3 magnitude struck central Italy with its epicentre near L'Aquila, at 42.3502° N, 13.3762° E. The earthquake damaged 3000 to 11 000 buildings in the medieval city of L'Aquila. Several buildings totally collapsed, 308 people were killed. The post emergency phase till now is just at its beginning step. Conventional surveying techniques using high precision total stations, GNSS receivers and laser scanners for investigations on damaged buildings are always becoming more automated, accurate and operative and even much more fast. Even if these techniques represent instruments of extreme operability there are still many evident limits on their use, especially regarding the survey of both the roofs and the facades of tall buildings or dangerous places, typical on post earthquake situations. So using micro UAVs for surveying in such particular cases, many of these problems can be easily bypassed. In fact, the present work aims on experimenting using multi-rotor micro UAVs, that will allow high quality image capturing on roofs and facades of structures in the old city center of L'Aquila. To obtain actual stereoscopic acquisitions of buildings some conditions on the geometry of acquisition have to be observed, for this reason, taking as a guideline classic flight photogrammetric, a flight planning software was developed. Accurate planning for UAVs acquisitions is very important also considering the reduced autonomy of such vehicles. This can be a strategic point if we want to use UAVs for early damage assessment and also for post event reconstruction planning.

Started in 2009, the COSMOCoast project aims to the investigation of the potential of Remote Sensing in support to the management of coastal areas. Particular attention is paid to the contribution ...

During 2002, as part of a collaboration between the National Civil Protection Department and the University of L'Aquila, a methodology for assessing the vulnerability of an urban center was developed. The methodology considered the urban territory as well as the complex of physical and functional relationships of the urbanized territory and not a simple summation of elements, in order to analyze simultaneously the multiple factors necessary to determine the vulnerability of the whole center. This methodology was applied to the city of L'Aquila and two other smaller towns, and in previous studies, some maps representing the possible vulnerability of buildings were prepared for the centre of the city of l’Aquila. These maps graduate the possible vulnerability in four different classes and have a maximum resolution of 25 m. After the earthquake in April 2009, it is possible to assess the accuracy of the model comparing predicted vulnerability with the map of fitness for human habitation realized after the earthquake. The vulnerability map considered the buildings situated on the emergency routes, therefore, the comparison was carried out only for these areas. After the seismic event, the map of fitness for human habitation and the actual post-earthquake damage were available: these results were archived in an Access database and also mapped on a 1:2,000 city map. To assure the consistency of these data, Access databases were geocoded and so cross checked with the results reported in the map files. The maps so obtained and verified were compared with the maps of the predicted vulnerability, rasterizing the information reported on the two maps at the same resolution. Thus, it has obtained a raster file containing differences between the vulnerability predicted and observed damages, evidencing that the biggest differences are limited to some small areas. Observing the localization of these areas, it seems that there may exist a correlation between biggest mismatch and some geophysical characteristics of the terrain that can cause local attenuation or amplification of the seismic waves. However, further investigations have to be carried on to confirm these initial results. The main elaborations were performed in open-source packages: GRASS, Q-GIS, and gvSIG.

This paper describes the monitoring system planned to measure the displacements of an extremely slow landslide in an alpine glacial valley in Northern Italy. Because of the smallness of the displacements, normally less than 1 cm/year, great attention has been paid to evaluate the reliability of the measurements by evaluating their precision and accuracy. For this purpose it was essential to make the system redundant by measuring the displacements with at least two different techniques: the inclinometers to monitor the subsurface displacements and the Total Station for measuring the surface displacements. With the increase of redundancy of the measures, there are more information to describe the landslide in terms of displacements, directions and rate, both superficial and deep. In this way, movements are better investigated and it is possible to highlight eventual disagree between the different techniques of measurement and improve the result’s accuracy. The paper focuses mainly on the characteristics of the network used with the Total Station, in order to define how they affect the precision and accuracy of the measurements. Thus, the aim of this research has been to derive some conclusions about the optimal monitoring surveying network in terms of reliability and precision, compatible with the type of slope movements and the morphology of the site. The strategies of elaboration and results obtained are presented in this paper.

An Unmanned Aerial Vehicle (UAV) is an aircraft without a human pilot on board. UAVs allow close-range photogrammetric acquisitions potentially useful for building large-scale cartography and acquisitions of building geometry. This is particularly useful in emergency situations where major accessibility problems limit the possibility of using conventional surveys. Presently, however, flights of this class of UAV are planned based only on the pilot's experience and they often acquire three or more times the number of images needed. This is clearly a time-consuming and autonomy-reducing procedure, which is certainly detrimental when extensive surveys are needed. For this reason new software, to plan the UAV's survey will be illustrated.

The old city center of L’Aquila is rich in historical buildings of considerable merit. On April 6

On April 6, 2009, an earthquake hit the old city of L’Aquila resulting in hundreds of victims and thousands of collapsed structures. The post emergency and very crucial phase regarding surveys, structure controls and investigations till now is fully underway. Conventional surveying techniques using high precision total stations, GNSS and laser scanners, are instruments of extreme operability but there are still many limits on their use, especially regarding the survey of both the roofs and the facades of tall buildings or dangerous places, typical in post earthquake situations. Another very important disadvantage of the traditional surveying, especially during the post seismic periods, is the overall safety of the instruments, operators and workers. In particular, the seismic sequence that may last for months after the main shock, causing collapse and damage that in most cases can also damage the transport and communication infrastructure. This creates important problems for all instruments located in that area and definitely poses further serious risk for all operators. Moreover, some surveys have to be repeated periodically in order to achieve a final result. On the other hand, by using micro UAVs (Unmanned Aerial Vehicles) for surveying in such particular scenarios, many of these problems can easily bypassed. For example, there are no accessibility problems for an UAV mainly because of its extreme flying capabilities that can really permit the access of virtually any place. Regarding the security, these instruments are fully remotely controlled, so they do not involve any risk for the operators simply because they are in the dangerous area. For these reasons, in this work, the authors explain the advantages of multirotor UAVs

On April 6, 2009, an earthquake hit the historic center of L’Aquila city, hundreds of victims, thousands of collapses. During the post-emergency a continuous monitoring of all building is crucial in order to guarantee that each structure at least will not worsen its stability until the final reconstruction is completed. So detailed surveying of all building is performed using different geomatic techniques as total stations, land photogrammetry, and laser scanners. Even if all these techniques can perfectly respond to many crucial post hazard needs, there are still many monitoring that cannot be completely carried on with traditional techniques. For these reasons, in this work, the advantages of using multirotor UAVs will be illustrated; UAVs can be fully remote controlled and so the geometry of photogrammetric image acquisition can be imposed.

Recent events reveal that the use of very high resolution satellite images for “early damage assessment” after seismic events can be very useful and call for deeper investigation by the scientific community. In the present study five monoscopic panchromatic images covering the historical citycenter of L’Aquila, GCPs and DEMs from medium scale cartography were used because they are frequently utilized in emergency applications. The interest was to make a deeper investigation on geometric characteristics of those images, that were not fully investigated by the scientific community and to study the detection capabilities for the specific post seismic application, so several orientation and detection tests were executed.

SUMMARY Here we report the preliminary results of GPS data inversions for coseismic and initial afterslip distributions of the Mw 6.3 2009 April 6 L’Aquila earthquake. Coseismic displacements of continuous and survey-style GPS sites, show that the earthquake ruptured a planar SW-dipping normal fault with ∼0.6 m average slip and an estimated moment of 3.9 × 1018 Nm. Geodetic data agree with the seismological and geological information pointing out the Paganica fault, as the causative structure of the main shock. The position of the hypocentre relative to the coseismic slip distribution supports the seismological evidence of southeastward rupture directivity. These results also point out that the main coseismic asperity probably ended downdip of the Paganica village at a depth of few kilometres in agreement with the small (1–10 cm) observed surface breaks. Time-dependent post-seismic displacements have been modelled with an exponential function. The average value of the estimated characteristic times for near-field sites in the hanging-wall of the fault is 23.9 ± 5.4 d. The comparison between coseismic slip and post-seismic displacements for the first 60 d after the main shock, shows that afterslip occurred at the edges of the main coseismic asperity with a maximum estimated slip of ∼25 cm and an equivalent seismic moment of 6.5 × 1017 Nm. The activation of the Paganica fault, spatially intermediate between the previously recognized main active fault systems, suggests that strain accumulation in the central Apennines may be simultaneously active on distinct parallel fault systems.

In the references erroneously books where cited instead of single papers therein. This applies to: Guarascio M et al (2007) Safety and security engineering II. WIT Press, South Hampton It should read: Guarascio, M, Lombardi M, Rossi G, Sciarra G (2007) “Risk analysis and acceptability criteria” In: Guarascio,M. et alWIT Transactions on the Built Environment 94, pp. 131-138 and to Guarascio et al (2009) It should read: Guarascio, M. et al. (2009)Geostatistics/Reliability based Risk analysis of the Vajont landslide WIT Transactions on the Built Environment 108, pp. 607-615