Table 5 Rock Tunneling quality index, Q-system determined as follow
Parameter | Description | Value |
|---|---|---|
RQD | Rock Quality Designation | 50 |
Jn | Joint Number | 4 |
Jr | Joint Roughness | 3 |
Ja | Joint Alteration | 1 |
Jw | Joint Water Reduction Factor | 1 |
SRF | Stress Reduction Factor | 1.13 |
Total Q-System | Â | 1.87 Poor rock |