High-Resolution 3D FEM Stability Analysis of the Sabereebi Cave Monastery, Georgia

Abstract

This study assesses the static stability of the artificial Sabereebi Cave Monastery southeast of Georgia's capital, Tbilisi. The cliff into which these Georgian-Orthodox caverns, chapels, and churches were carved consists of a five-layered sequence of weak sedimentary rock—all of which bear a considerable failure potential and, consequently, pose the challenge of preservation to geologists, engineers, and archaeologists. In the first part of this study, we present a strategy to process point cloud data from drone photogrammetry as well as from laser scanners acquired in- and outside the caves into high-resolution CAD objects that can be used for numerical modeling ranging from macro- to micro-scale. In the second part, we explore four distinct series of static elasto-plastic finite element stability models featuring different levels of detail, each of which focuses on specific geomechanical scenarios such as classic landsliding due to overburden, deformation of architectural features as a result of stress concentration, material response to weathering, and pillar failure due to vertical load. With this bipartite approach, the study serves as a comprehensive 3D stability assessment of the Sabereebi Cave Monastery on the one hand; on the other hand, the established procedure should serve as a pilot scheme, which could be adapted to different sites in the future combining non-invasive and relatively cost-efficient assessment methods, data processing and hazard estimation.

3D data integration for geo-located cave mapping based on unmanned aerial vehicle and terrestrial laser scanner data

“…The lightless environment made it difficult to capture accurate measurements, and the complex geometry and difficult ground conditions made it challenging to establish reference points for the system. Despite these challenges, the margins of error obtained from both the TLS and UAV systems were lower than 0.25 meter which is acceptable for most applications (Šašak et al 2019;Domej et al 2022). Overall, the combination of TLS and UAV systems in producing sensitive and accurate data for the cave interior and its surface topography was successful.…”

“…The integration of the data obtained from these two systems provides critical information when conducting 3D analyzes in studies where the interior morphology of the cave and the surface topography should be evaluated together. A review of past cave papers using integrated UAV and TLS systems to generate data from inside and outside the cave shows that there is only one study in the literature that has analyzed the stability of man-made monastery caves (Domej et al 2022). The present study is the first one to analyze the internal and external relationship of a natural cave with complex geometry using TLS and UAV systems.…”

A Review of Point Cloud Segmentation of Architectural Cultural Heritage

“…(Liu Q, 2009). Most of the studies targeting architectural cultural heritage are disease extraction (Alkadri et al, 2022), heritage restoration (Hou M et al, 2018), deformation monitoring (Domej et al, 2022), and digitization and documentation (Dzieglewski, 2015). In this paper, we mainly focus on point cloud segmentation of various historical buildings, cultural sites, and ancient building complexes to summarize.…”