The village of Črnotiče lies near Črni Kal, beneath the steep slopes of the Karst Edge. Natural erosion processes and rock weathering have caused recurring rockfalls in the area above the village for several years, posing a threat to the residential buildings and public infrastructure below.
As the investor, the Municipality of Koper initiated preventive measures to stabilise the slope and secure a large unstable rock block. Following a public tender, our company was selected to carry out the works in accordance with the project documentation.
Active rock slope stabilisation
Before commencing the main works, we inspected the project area, carried out the necessary clearance of low-growing vegetation and other trees, and removed unstable sections of rock.
Temporary protection for the residential buildings below the rock face was provided by installing a protective barrier designed to retain smaller rock fragments and stones during slope cleaning and remediation works.
The main part of the intervention involved stabilising a large unstable rock block on a rock face approximately 15 metres high. The estimated volume of the rock mass is approximately 25 m³.
To ensure greater stability, we implemented an active stabilisation system comprising:
- Reinforced-concrete support columns to provide additional support to the large unstable rock mass;
- Anchoring of the support columns using 12-metre-long anchors;
- High-tensile protective mesh to provide additional protection for the rock slope;
- Anchoring of the protective mesh using anchors ranging from 9 to 12 metres in length.
The combination of the support structure, anchoring system and high-tensile mesh provides an integrated solution for the critical area, improving slope stability and reducing the risk associated with the movement or disintegration of rock blocks.
Improved safety for residents and infrastructure
The remediation measures improve safety conditions for residents living in the three residential buildings below the rock edge while also providing additional protection for public infrastructure in the area.
An important component of the project is the planned two-year monitoring programme for the rock face in the critical section of the Karst Edge. Monitoring will enable timely detection of potential changes and provide an additional basis for the continued assessment of the stabilised area’s long-term stability.
