Rock slope protection D501
The unstable slope is located on the left side of state road D501, south of the settlement Hreljin, northeast of the fast road A7 and west of the fortress “Hreljin”.
State road D501 was conducting with cutting in natural terrain. As a result, opened cuts 2,0-18,0 m in height were formed in rock mass in the total length of 300 m.
Engineering-geological and geotechnical exploration works were executed for the purpose of slope protection design (geotechnical part).
The rock slope protection included an application of the following mitigation measures:
- reinforced concrete filling
- rock bolt
- self-drilling rock bolts
- barrier protection
- mesh protection
- mesh reinforced with steel ropes
Beginning of the slope section covered with ivy, after clearing of vegetation, clay, rocks and loose blocks, was protected with the execution of shotcrete leveling layer, rock bolts (length L = 1.0 m) and shotcrete C 24/30, 10.0 cm in thickness (two layers of 5.0 cm and mesh Q188).
Self-drilling rock bolts diameter Φ 32, length L = 3.0 m, combined with shotcrete, reinforced mesh and drains were built in to prevent further rockfall of smaller unstable blocks in order to eliminate any hydrostatic pressure behind shotcrete.
Galvanized double twisted hexagonal protective steel mesh 8×10 was executed on parts of the slope to prevent rockfall. Filling of major irregularities and cavities in several slope sections was performed with reinforced filling.