Geotechnical Challenges and Stabilization Interventions in Three Greek Show Caves of Monumental Value
Geotechnical Challenges and Stabilization Interventions in Three Greek Show Caves of Monumental Value
Abstract
Show caves are natural underground systems adapted for public access while often preserving archaeological, palaeontological, and geomorphological features of exceptional value. Their geotechnical management must reconcile visitor safety, monument-preservation constraints, and long-term performance under aggressive microclimatic conditions and high seismicity. This paper presents a mechanism-driven engineering framework for the investigation, analysis, design, and implementation of stabilization measures in such environments, illustrated through three Greek show caves of contrasting geotechnical character: Dikteon Cave (Crete), Theopetra Cave (Thessaly), and Petralona Cave (Chalkidiki). The regulatory framework used for the analyses are Eurocode 7 (CEN, 2004a) and Eurocode 8 (CEN, 2004b).
At Dikteon Cave, discontinuity mapping and kinematic analysis identified a limited number of structurally controlled roof wedges governing stability; these were stabilised by discrete, fully grouted stainless-steel anchors with minimal visual impact. At Theopetra Cave, the dominant hazard is external rockfall from steep slopes above the entrance and visitor route; the adopted solution combines selective reinforcement of unstable blocks with rockfall protection systems designed on the basis of stability analyses and rockfall trajectory and energy simulations. At Petralona Cave, the principal issue is the long-term stability of a near-vertical archaeological section excavated in heterogeneous infill deposits; stabilization was based on conservative characterisation, low-pressure grouting, highly limited reinforcement, and an observational approach supported by monitoring.
The three case histories demonstrate how a common engineering workflow can be adapted to fundamentally different instability mechanisms and material behaviours, and show that effective and heritage-compatible stabilization of show caves can be achieved through targeted, mechanism-driven interventions rather than through generalised or visually intrusive measures.
Keywords: Greek monumental caves; geotechnical engineering; Rock-mass stabilization; passive anchors; rockfall protection; cultural heritage
Dimitrios Egglezos; Emmanouil Tzannidakis; Charalambos Gouvas; Antonis Galanakis
4th International Symposium on the Preservation of Monuments and Historic Sites
Underground Monuments and Rock Engineering
https://doi.org/10.53243/tc301-2026-94