Enrique Valdelamar Martínez David, Saba Manuel, Torres Gil Leydy Karina
Civil Engineering Program, Universidad de Cartagena, Calle 30 # 48-152, Cartagena, Colombia.
Heliyon. 2024 Feb 6;10(3):e25612. doi: 10.1016/j.heliyon.2024.e25612. eCollection 2024 Feb 15.
The discernment of asbestos-cement (AC) roofs within urban areas stands as a pivotal concern pertinent to communal well-being and ecological oversight, particularly in emerging nations where asbestos continues to be extensively employed. Conventional methodologies entailing the recognition of asbestos-cement roofs and the characterization of their degradation status, such as tangible examinations and laboratory assays, prove to be temporally protracted, financially demanding, and arduous to extrapolate comprehensively across expansive urban domains. In this paper, it is presented a novel approach for identifying asbestos-cement roofs in urban areas using hyperspectral airborne acquisition and carry out a diagnosis that allows to identify the state of asbestos-cement roofs and thus provide a tool for the competent authorities to develop and prioritize intervention strategies to mitigate the problem. Four different methodologies were implemented and compared, three of which are new in the literature, to identify the deterioration of asbestos-cement (AC) roof state in large urban areas. This, in turn, furnishes a tool for competent authorities to identify the state of AC roofs, develop and prioritize intervention strategies to mitigate the problem. The control points in field allowed validating the classification and the proposed methodology for the prioritization of intervention in AC roofs. Some neighborhoods in the city showed peaks in the area of asbestos-cement roofs of 47% of the total area of the neighborhood, representing practically all of the roofs present in the neighborhood. On average around 20% of the total area of a neighborhood in Cartagena is covered by AC. Furthermore, it was found a total area of AC roofs throughout the city of more than 9 km (9 million square meters). On the other hand, two of the 4 methods used showed encouraging results that demonstrate their ability to identify covers in poor and good condition at a large scale from hyperspectral images. This academic novelty suggests that there is a possibility of practical application of these methods in other urban contexts with high concentrations of AC roofs, helping in the planning and optimization of intervention strategies to mitigate the risk in public and environmental health due to the presence of asbestos.
在城市地区识别石棉水泥（AC）屋顶是关乎公共福祉和生态监管的关键问题，尤其是在石棉仍被广泛使用的新兴国家。诸如实地检查和实验室检测等识别石棉水泥屋顶及其降解状态特征的传统方法，在时间上耗时长久，成本高昂，且难以在广阔的城市区域全面推广。本文提出了一种利用高光谱航空采集识别城市地区石棉水泥屋顶的新方法，并进行诊断，以确定石棉水泥屋顶的状态，从而为相关主管部门制定和优化干预策略以缓解问题提供工具。实施并比较了四种不同方法，其中三种是文献中的新方法，用于识别大城市地区石棉水泥（AC）屋顶状态的恶化情况。这反过来为相关主管部门提供了一种工具，以识别AC屋顶的状态，制定和优化干预策略以缓解问题。实地控制点有助于验证分类以及AC屋顶干预优先级的提议方法。该市的一些社区显示，石棉水泥屋顶面积占社区总面积的47%，几乎涵盖了社区内所有屋顶。在卡塔赫纳，平均约20%的社区总面积被AC覆盖。此外，发现整个城市的AC屋顶总面积超过9平方千米（900万平方米）。另一方面，所使用的4种方法中有两种显示出令人鼓舞的结果，表明它们能够从高光谱图像中大规模识别状况良好和较差的覆盖物。这一学术新成果表明，这些方法有可能在其他AC屋顶集中的城市环境中实际应用，有助于规划和优化干预策略，以减轻因石棉存在而对公众健康和环境健康造成的风险。
