All in-text references underlined in blue are linked to publications on ResearchGate, letting you... more All in-text references underlined in blue are linked to publications on ResearchGate, letting you access and read them immediately.
L'intervento condotto a San Salvatore di Cabras nel 2000 aveva lo scopo di verificare le cond... more L'intervento condotto a San Salvatore di Cabras nel 2000 aveva lo scopo di verificare le condizioni di conservazione dell'ipogeo di San Salvatore e di superare le criticita relative sia agli impianti di ventilazione che al controllo delle acque piovane. E' stato possibile nella stessa occasione effettuare le indagini geofisiche dell'area e condurre una seppur limitata indagine archeologica. In order to solve the problems related to both the arrangement of the ventilation systems and the control of rain water and ground water into the hypogeum of San Salvatore di Sinis, (Cabras, Sardinia, Italy), preparatory work was carried out in the external part of the church. On the same occasion a characterization of both the whole building and the subsoil of the surrounding area was also conducted by means of geophysical methods and an even limited archaeological campaign. Geophysical prospection has shown the pathways of waters and the probable existence of other buried rooms ...
Vertical differential settlement of buildings is produced by both natural and/or anthropogenic di... more Vertical differential settlement of buildings is produced by both natural and/or anthropogenic disturbances of the foundation soil, such as, for example, differential consolidation, circulation of water due to rupture of water pipes, seepage, suction, vibrations induced by vehicle traffic, excavations, construction defects and an incorrect design/execution of the work. Techniques of soil consolidation and stabilization by means of expanding resin injections are being advantageously employed to mitigate or even solve this issue. The resin used is a two-component polyurethane compound that, once its chemical reaction is completed, reaches an inert and lightweight solid state so that it is environment-safe and perfectly compatible with the injected soil. The resin is injected directly into the critical volumes by means of small diameter pipes. After the injection, the resin expands rapidly in the soil through an irreversible exothermic chemical reaction, so that it actively counteracts the settlement and its causes. Indeed, the observed effects are threefold: i) filling voids; ii) compacting soil; iii) reducing/removing interstitial water. Among the possible procedures to monitor soil consolidation and stabilization by injections of expanding resins, a procedure is hereafter described which involves the use of electrical resistivity tomography (ERT). The rationale for the use of this non-invasive imaging technique is that electrical resistivity is a physical property sensitive to grain size, porosity and water content of sediments and to voids. Therefore, it can both acquire information about the subsurface structure, also from volumes of difficult access (e.g.,, below the foundations and the floor of the building), which is necessary for the consolidation project, and it can monitor the injection work in progress, in addition to traditional geotechnical testing. Specifically, the process is divided into several steps. A 3D-ERT is acquired first, covering both the volumes affected by the settlement and nearby stable volumes of soil underlying the footprint of the building, to accurately map the different resistivity that characterizes the anomalous volumes. The 3D resistivity model is integrated, wherever necessary, by geotechnical investigations, mainly penetration tests and sample identification, so as to optimally design the injection points, in terms of position, depth and number. During injections, the 3D-ERT and some geotechnical tests are repeated to check progressively the effects obtained by the treatment, so as to allow, if necessary, to modify the injection scheme until reaching the predetermined target, i.e., obtaining the greatest uniformity of chemical and physical characteristics between the stabilized volumes and the nearby stable ones, which are used as a reference. In some sites, where the settlement was stabilized by the above procedure, it was also possible to repeat a 3D-ERT after several years: results confirmed that the situation of the subsurface just after the injections had remained almost unaltered and the effectiveness of the procedure over time was demonstrated. The above approach is described hereafter and is accompanied by the description of the results from a specifically planned test site and from two work sites, selected as examples
The Differential Synthetic Aperture Radar Interferometry (DInSAR) is a remote sensing technique t... more The Differential Synthetic Aperture Radar Interferometry (DInSAR) is a remote sensing technique that allows us to produce spatially dense deformation maps with centimetre to millimetre accuracy and to detect and follow the temporal evolution of deformations via the generation of time – series. To do this, the information available from each interferometric data pair must be properly related to those included in the other acquisitions, via the generation of an appropriate sequence of DInSAR Interferograms. In this work we process a large set of data acquired by the European Remote Sensing (ERS) satellites on the Palau y Solitari de Plegamans area located near Barcelona (Spain) and on the Cagliari area (Italy). In the second work we apply an algorithm referred to as Small Baseline Subset (SBAS) proposed by I.R.E.A. - C.N.R. The results demonstrate that the DInSAR technique is a fast and precise method to detect and follow the temporal evolution of deformations, so it is a powerful tec...
Nel mese di febbraio 2002 e stato siglato tra l’Institut National des Sciences de l’Archeologie e... more Nel mese di febbraio 2002 e stato siglato tra l’Institut National des Sciences de l’Archeologie et du Patrimoine, la Universite Hassan II, Faculte des Lettres et Sciences Humaines, Mohammedia (Maroc) e l’Universita di Sassari un protocollo d’accordo relativo alla lettura urbanologica del centro di Lixus per la definizione del forum e degli edifici caratteristici dell’area forense. La ricerca e, dunque, inerente la localizzazione del forum di Lixus attraverso differenti metodi di indagine comprendenti l’analisi delle foto aeree e della cartografia, rilievi geofisici, scavi, rilievi, per giungere alla valorizzazione e all’edizione dell’area indagata.
Archaeological sites in rural areas are often characterized by structural remains that are made o... more Archaeological sites in rural areas are often characterized by structural remains that are made of mud or raw brick, and that produce a very small contrast in physical characteristics, as the surrounding materials of both anthropogenic and natural origins have similar lithological and mineralogical properties. The main measurable differences are due to changes in compaction and porosity and, as a consequence, in permeability, which influence the hydrological behaviour of the subsurface materials. In this paper, we present some applications based on Electrical Resistivity Tomography (ERT) surveys that are routinely applied in archaeological prospection, carried out over two different weather conditions. Measurement of the changing resistivity, corresponding to different moisture conditions in the subsoil, allowed us to identify archaeological strata and structures surrounded by natural, undisturbed soil. A number of tests carried out on a physical model permitted a further definition...
All in-text references underlined in blue are linked to publications on ResearchGate, letting you... more All in-text references underlined in blue are linked to publications on ResearchGate, letting you access and read them immediately.
L'intervento condotto a San Salvatore di Cabras nel 2000 aveva lo scopo di verificare le cond... more L'intervento condotto a San Salvatore di Cabras nel 2000 aveva lo scopo di verificare le condizioni di conservazione dell'ipogeo di San Salvatore e di superare le criticita relative sia agli impianti di ventilazione che al controllo delle acque piovane. E' stato possibile nella stessa occasione effettuare le indagini geofisiche dell'area e condurre una seppur limitata indagine archeologica. In order to solve the problems related to both the arrangement of the ventilation systems and the control of rain water and ground water into the hypogeum of San Salvatore di Sinis, (Cabras, Sardinia, Italy), preparatory work was carried out in the external part of the church. On the same occasion a characterization of both the whole building and the subsoil of the surrounding area was also conducted by means of geophysical methods and an even limited archaeological campaign. Geophysical prospection has shown the pathways of waters and the probable existence of other buried rooms ...
Vertical differential settlement of buildings is produced by both natural and/or anthropogenic di... more Vertical differential settlement of buildings is produced by both natural and/or anthropogenic disturbances of the foundation soil, such as, for example, differential consolidation, circulation of water due to rupture of water pipes, seepage, suction, vibrations induced by vehicle traffic, excavations, construction defects and an incorrect design/execution of the work. Techniques of soil consolidation and stabilization by means of expanding resin injections are being advantageously employed to mitigate or even solve this issue. The resin used is a two-component polyurethane compound that, once its chemical reaction is completed, reaches an inert and lightweight solid state so that it is environment-safe and perfectly compatible with the injected soil. The resin is injected directly into the critical volumes by means of small diameter pipes. After the injection, the resin expands rapidly in the soil through an irreversible exothermic chemical reaction, so that it actively counteracts the settlement and its causes. Indeed, the observed effects are threefold: i) filling voids; ii) compacting soil; iii) reducing/removing interstitial water. Among the possible procedures to monitor soil consolidation and stabilization by injections of expanding resins, a procedure is hereafter described which involves the use of electrical resistivity tomography (ERT). The rationale for the use of this non-invasive imaging technique is that electrical resistivity is a physical property sensitive to grain size, porosity and water content of sediments and to voids. Therefore, it can both acquire information about the subsurface structure, also from volumes of difficult access (e.g.,, below the foundations and the floor of the building), which is necessary for the consolidation project, and it can monitor the injection work in progress, in addition to traditional geotechnical testing. Specifically, the process is divided into several steps. A 3D-ERT is acquired first, covering both the volumes affected by the settlement and nearby stable volumes of soil underlying the footprint of the building, to accurately map the different resistivity that characterizes the anomalous volumes. The 3D resistivity model is integrated, wherever necessary, by geotechnical investigations, mainly penetration tests and sample identification, so as to optimally design the injection points, in terms of position, depth and number. During injections, the 3D-ERT and some geotechnical tests are repeated to check progressively the effects obtained by the treatment, so as to allow, if necessary, to modify the injection scheme until reaching the predetermined target, i.e., obtaining the greatest uniformity of chemical and physical characteristics between the stabilized volumes and the nearby stable ones, which are used as a reference. In some sites, where the settlement was stabilized by the above procedure, it was also possible to repeat a 3D-ERT after several years: results confirmed that the situation of the subsurface just after the injections had remained almost unaltered and the effectiveness of the procedure over time was demonstrated. The above approach is described hereafter and is accompanied by the description of the results from a specifically planned test site and from two work sites, selected as examples
The Differential Synthetic Aperture Radar Interferometry (DInSAR) is a remote sensing technique t... more The Differential Synthetic Aperture Radar Interferometry (DInSAR) is a remote sensing technique that allows us to produce spatially dense deformation maps with centimetre to millimetre accuracy and to detect and follow the temporal evolution of deformations via the generation of time – series. To do this, the information available from each interferometric data pair must be properly related to those included in the other acquisitions, via the generation of an appropriate sequence of DInSAR Interferograms. In this work we process a large set of data acquired by the European Remote Sensing (ERS) satellites on the Palau y Solitari de Plegamans area located near Barcelona (Spain) and on the Cagliari area (Italy). In the second work we apply an algorithm referred to as Small Baseline Subset (SBAS) proposed by I.R.E.A. - C.N.R. The results demonstrate that the DInSAR technique is a fast and precise method to detect and follow the temporal evolution of deformations, so it is a powerful tec...
Nel mese di febbraio 2002 e stato siglato tra l’Institut National des Sciences de l’Archeologie e... more Nel mese di febbraio 2002 e stato siglato tra l’Institut National des Sciences de l’Archeologie et du Patrimoine, la Universite Hassan II, Faculte des Lettres et Sciences Humaines, Mohammedia (Maroc) e l’Universita di Sassari un protocollo d’accordo relativo alla lettura urbanologica del centro di Lixus per la definizione del forum e degli edifici caratteristici dell’area forense. La ricerca e, dunque, inerente la localizzazione del forum di Lixus attraverso differenti metodi di indagine comprendenti l’analisi delle foto aeree e della cartografia, rilievi geofisici, scavi, rilievi, per giungere alla valorizzazione e all’edizione dell’area indagata.
Archaeological sites in rural areas are often characterized by structural remains that are made o... more Archaeological sites in rural areas are often characterized by structural remains that are made of mud or raw brick, and that produce a very small contrast in physical characteristics, as the surrounding materials of both anthropogenic and natural origins have similar lithological and mineralogical properties. The main measurable differences are due to changes in compaction and porosity and, as a consequence, in permeability, which influence the hydrological behaviour of the subsurface materials. In this paper, we present some applications based on Electrical Resistivity Tomography (ERT) surveys that are routinely applied in archaeological prospection, carried out over two different weather conditions. Measurement of the changing resistivity, corresponding to different moisture conditions in the subsoil, allowed us to identify archaeological strata and structures surrounded by natural, undisturbed soil. A number of tests carried out on a physical model permitted a further definition...
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