In this note we present the results obtained in four consecutive Terrestrial Laser Scanner surveys of a landslide of 10 ha, without any stable areas within the detected scenario and the processing aimed at the evaluation of the changes in the morphology of the landslide area. For this purpose, have been adopted several methods which could be considered as complementary to one another: direct adaptation of point clouds, differentiation of DEMs (Digital Elevation Models), elevation profiles along the same sections at different epochs. Particular attention has been devoted to the estimation of the amount of mobilized material, calculated through the differentiation of DEMs; evaluation of mobilized masses is particularly significant if performed considering the different landslide bodies in which it is articulated the slope. As a matter of fact, landslide bodies may have different behaviors, depending on the generation to which they belong, on their slope and on their lithology. The delimitation of the various landslide bodies was performed on the basis of geomorphological maps (slope, aspect, curvature) extracted from the DEM. To obtain these results it is necessary to overcome various problems, in particular the stability of the reference frame adopted for the geo-referencing and the interpolation of an actually reliable DEM. Terrestrial Laser Scanner allows to obtain good results in landslide monitoring providing that a set of procedures has been carefully applied for the execution of the scans, their co-registration, georeferencing and for the interpolation of DEM.
Nella nota si presentano i risultati ottenuti in quattro rilievi successivi effettuati tramite Laser Scanner Terrestre di una frana di circa 10 ha priva di aree stabili all’interno dello scenario rilevato e le elaborazioni finalizzate alla valutazione della variazione di forma subita dalla superficie della frana. A questo scopo sono stati adottati vari metodi tra loro complementari, l’adattamento diretto delle nubi, la differenziazione di grid DEM (Digital Elevation Models), l’estrazione dei profili altimetrici lungo le stesse sezioni alle varie epoche di rilievo. Si è dedicata particolare attenzione alla stima della quantità di materiale mobilitato, calcolata per differenziazione di DEM; la valutazione delle masse mobilitate da un'epoca all'altra di rilievo all’altro è particolarmente significativa se riferita ai diversi corpi di frana nei quali si articola il versante, che possono presentare comportamenti differenti in funzione della generazione alla quale appartengono, della pendenza e della litologia. La delimitazione dei vari corpi di frana è stata eseguita sulla base di carte di caratteristiche geomorfologiche (pendenza, esposizione, curvatura) estratte dal DEM. Per ottenere questi risultati è necessario superare varie criticità, in particolare la stabilità del riferimento per la georeferenziazione e la interpolazione di un DEM realmente affidabile. Il Laser Scanner Terrestre può essere impiegato con buoni risultati anche per il monitoraggio di frane purché siano applicate attente procedure per l’esecuzione delle scansioni, la loro co-registrazione e georeferenziazione e la realizzazione del DEM.
Rilievi multi-temporali con laser scanner terrestre per il monitoraggio di una frana
Maurizio Barbarella;Margherita Fiani;
2015-01-01
Abstract
In this note we present the results obtained in four consecutive Terrestrial Laser Scanner surveys of a landslide of 10 ha, without any stable areas within the detected scenario and the processing aimed at the evaluation of the changes in the morphology of the landslide area. For this purpose, have been adopted several methods which could be considered as complementary to one another: direct adaptation of point clouds, differentiation of DEMs (Digital Elevation Models), elevation profiles along the same sections at different epochs. Particular attention has been devoted to the estimation of the amount of mobilized material, calculated through the differentiation of DEMs; evaluation of mobilized masses is particularly significant if performed considering the different landslide bodies in which it is articulated the slope. As a matter of fact, landslide bodies may have different behaviors, depending on the generation to which they belong, on their slope and on their lithology. The delimitation of the various landslide bodies was performed on the basis of geomorphological maps (slope, aspect, curvature) extracted from the DEM. To obtain these results it is necessary to overcome various problems, in particular the stability of the reference frame adopted for the geo-referencing and the interpolation of an actually reliable DEM. Terrestrial Laser Scanner allows to obtain good results in landslide monitoring providing that a set of procedures has been carefully applied for the execution of the scans, their co-registration, georeferencing and for the interpolation of DEM.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.