Maľa M., Greif V. & Vlčko J., 2026: 3D geomechanical analysis of rock mass stability of the Spiš Castle (Slovakia) using high-resolution point cloud data. Acta Geologica Slovaca, 18, 1, 23–33.

3D geomechanical analysis of rock mass stability of the Spiš Castle (Slovakia) using high-resolution point cloud data

Martin Maľa, Vladimír Greif & Ján Vlčko

Department of Engineering Geology, Hydrogeology and Applied Geophysics, Faculty of Natural Sciences, Comenius University Bratislava, Ilkovičova 6, 842 15 Bratislava, Slovakia; mala26@uniba.sk, vladimir.greif@uniba.sk, jan.vlcko@uniba.sk

Abstract

Conventional surveying techniques frequently prove inadequate in providing a detailed geomechanical assessment of rock masses, particularly in evaluating stability concerns related to culturally significant hilltop structures. At Spiš Castle in Eastern Slovakia the drone obtained high-resolution 3D point cloud data were employed to overcome these limitations, offering enhanced insight into the structural and kinematic characteristics of the underlying travertine mound. This approach enabled precise extraction of discontinuity geometries and facilitated identification of key instability mechanisms that may pose a threat to historical buildings, especially on the eastern and northern flanks of the site. The spatial distribution and orientation of discontinuities manifest a systematic pattern indicative of tectonic origin, which persists in influencing the mechanical integrity of the rock mass. A significant number of discontinuities meet the geometric prerequisites for planar failure, suggesting a conditional stability state that could be compromised by minor external disturbances. Although current evidence signifies minimal mass movement and an overall stable condition, the analysis identified several potentially unstable blocks. While these blocks do not pose an immediate threat, their structural context and vulnerability to climate induced stressors emphasise the necessity of continuous monitoring and re-evaluation. These findings highlight the value of remote sensing technologies in evaluating long-term geohazards threatening heritage sites.

Key words: rock mass stability, cultural heritage, Spiš Castle, remote sensing, structural analysis, kinematic analysis

Manuscript received: 2026-04-23

Revised version accepted: 2026-06-12