In this proceedings are shown the results of a research project about the mapping of asbestos cement roof sheets in the municipalities of Biassono, Lissone, Monza, Muggio? and Seregno (MB) above an area of about 65 km2. The study was performed using hyperspectral images collected on the 5th July 2013 with the aerial MIVIS (Multispectral Infrared and Visible Imaging Spectrometer) sensor that acquires data in 102 channels in the spectral interval between the visible and the thermal infrared regions. Furthermore, field measurements were performed with a portable spectroradiometer Fieldspec FR (ASD, USA) on roofing with different deterioration status, with the aim of investigating their spectral characteristics. The geometrical and the atmospheric corrections were followed by an automatic classification with the SAM (Spectral Angle Mapper) algorithm using a training set selected on the basis of orthophotos and of information about asbestos cement roof provided by the municipalities. Field measurements allowed to define a spectral index related to the albedo of asbestos cement sheets and to the presence on their surface of mosses and lichens that was used to distinguish deteriorated and preserved roofs through the aerial images. This approach allowed to suggest different priorities in removal to the municipalities, that is imposed in the PRAL (Lombardy Region Asbestos Plan) since 2005, which also set among the strategic objectives the removal of asbestos from the regional territory by ten years after the plan approval. Data on asbestos roofing sheets were handled in a GIS (Geographic Information System) to supply the municipalities with the cadastral references of each property that has to be restored.
In questo contributo sono presentati i risultati di un progetto di ricerca che ha avuto come obiettivo la mappatura delle coperture in cemento-amianto nei Comuni di Biassono, Lissone, Monza, Muggio? e Seregno (MB) su un'area di circa 65 km2. Lo studio ha previsto l'acquisizione di immagini iperspettrali in data 5 luglio 2013 tramite il sensore aviotrasportato MIVIS (Multispectral Infrared and Visible Imaging Spectrometer) operante in 102 canali nell'intervallo spettrale compreso tra il visibile e l'infrarosso termico. Sono inoltre state effettuate misure in campo con uno spettroradiometro portatile Fieldspec FR (ASD, USA) su coperture a diverso stato di deterioramento, allo scopo di caratterizzare il loro comportamento spettrale. Le immagini sono state corrette geometricamente ed atmosfericamente e successivamente classificate in modo automatico con l'algoritmo SAM (Spectral Angle Mapper) utilizzando un training set individuato con l'aiuto di ortofoto e sulla base di informazioni sulla presenza di coperture in cemento-amianto fornite dai Comuni. Le misure a terra hanno permesso di definire un indice spettrale relazionato all'albedo delle lastre in cemento-amianto e alla presenza di muschi e licheni sulle stesse che e? stato successivamente utilizzato per discriminare, a partire dalle immagini aeree, tetti piu? deteriorati da tetti meglio conservati. Tale approccio ha permesso di suggerire ai Comuni una diversa priorita? di intervento nella loro rimozione prevista dal PRAL (Piano Regionale Amianto Lombardia) redatto nel 2005, che pone tra gli obiettivi strategici l'eliminazione dell'amianto dal territorio lombardo entro dieci anni dalla sua entrata in vigore. I dati relativi alle coperture individuate sono stati gestiti in ambiente GIS (Geographic Information System) al fine di fornire ai Comuni il riferimento catastale di ogni singola proprieta? da sottoporre a bonifica.
Individuazione di coperture in cemento-amianto e del loro deterioramento da immagini iperspettrali
Monica Pepe;Gabriele Candiani;
2014
Abstract
In this proceedings are shown the results of a research project about the mapping of asbestos cement roof sheets in the municipalities of Biassono, Lissone, Monza, Muggio? and Seregno (MB) above an area of about 65 km2. The study was performed using hyperspectral images collected on the 5th July 2013 with the aerial MIVIS (Multispectral Infrared and Visible Imaging Spectrometer) sensor that acquires data in 102 channels in the spectral interval between the visible and the thermal infrared regions. Furthermore, field measurements were performed with a portable spectroradiometer Fieldspec FR (ASD, USA) on roofing with different deterioration status, with the aim of investigating their spectral characteristics. The geometrical and the atmospheric corrections were followed by an automatic classification with the SAM (Spectral Angle Mapper) algorithm using a training set selected on the basis of orthophotos and of information about asbestos cement roof provided by the municipalities. Field measurements allowed to define a spectral index related to the albedo of asbestos cement sheets and to the presence on their surface of mosses and lichens that was used to distinguish deteriorated and preserved roofs through the aerial images. This approach allowed to suggest different priorities in removal to the municipalities, that is imposed in the PRAL (Lombardy Region Asbestos Plan) since 2005, which also set among the strategic objectives the removal of asbestos from the regional territory by ten years after the plan approval. Data on asbestos roofing sheets were handled in a GIS (Geographic Information System) to supply the municipalities with the cadastral references of each property that has to be restored.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
