3D Modeling and Structural Monitoring of the Puka Pukara Archaeological Complex-Peru

Archaeological buildings are part of our national cultural heritage, have a legacy of historical significance, and are generators of economic benefits, due to tourist movements. Three-dimensional models have become a useful and significant tool for monitoring records, virtual reality, and structural analysis of architectural monuments. Aerial photogrammetry is the most employed method, it provides a complete model of the monument, incorporates a digital camera that can be used manually, placed on a drone, or on top of tripod instruments. Therefore, this method is versatile and can generate complete 3D models at the expense of longer processing times. This study proposes the 3D modeling and structural monitoring of the archaeological complex of Puka Pukara, to characterize the general state of damage of the monument, including inaccessible areas. The data generated from the area acquisition provided a thorough identification of the pathologies in the facades and walls. The results show highly deterministic 3D digital models that are then rigorously analyzed. The structural monitoring showed that the west wall and the east façade of the Puka Pukara enclosure show deterioration, cracks, deformations, and a high risk of decline, so emergency actions are recommended for their stabilization. The paper presented a single case study where a single 3D scanning technique was applied to the archaeological complex of Puka Pukara. The results generated by the methodology allowed complete digitization (exterior and interior) with a high level of detail of the structures, which can only be achieved by using one methodology (photogrammetry)

Close-Range Sensing and Data Fusion for Built Heritage Inspection and Monitoring - A Review

Built cultural heritage is under constant threat due to environmental pressures, anthropogenic damages, and interventions. Understanding the preservation state of monuments and historical structures, and the factors that alter their architectural and structural characteristics through time, is crucial for ensuring their protection. Therefore, inspection and monitoring techniques are essential for heritage preservation, as they enable knowledge about the altering factors that put built cultural heritage at risk, by recording their immediate effects on monuments and historic structures. Nondestructive evaluations with close-range sensing techniques play a crucial role in monitoring. However, data recorded by different sensors are frequently processed separately, which hinders integrated use, visualization, and interpretation. This article’s aim is twofold: i) to present an overview of close-range sensing techniques frequently applied to evaluate built heritage conditions, and ii) to review the progress made regarding the fusion of multi-sensor data recorded by them. Particular emphasis is given to the integration of data from metric surveying and from recording techniques that are traditionally non-metric. The article attempts to shed light on the problems of the individual and integrated use of image-based modeling, laser scanning, thermography, multispectral imaging, ground penetrating radar, and ultrasonic testing, giving heritage practitioners a point of reference for the successful implementation of multidisciplinary approaches for built cultural heritage scientific investigations