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| 1. Rock mass rating (RMR) |
| Average values of input parameters of RMR | Uniaxial compressive strength (UCS) | Rock quality designation (RQD) | Discontinuities spacing | Discontinuities condition | Ground water condition | Discontinuities orientation | RMR |
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| Bore hole | Rock type |
| BH-1 at chainage 0 + 000 to 2 + 750 | Granite | 125.4 | 87% | 200 to 600 mm | Rough, hard filling < 5 mm, slightly weathered, persistent < 1 mm, and aperture < 0.1 mm | Dry | Very favorable to fair | 75.67 |
| Rating | 12 | 17 | 10 | 25 | 15 | −3.33 | |
| BH-2 | Quartz mica schist | 54.18 | 50% | <60 mm | Rough to slightly rough, hard filling < 5 mm, unweathered, persistent 1–3 m to 3–10 m, and aperture 0.1 to 1 mm | Dry | Very favorable to favorable | 59.00 |
| Rating | 7 | 13 | 5 | 21 | 15 | −2 |
| BH-3 | Calcareous quartzite | 106.7 | 80% | 60 to 200 mm | Rough to slightly rough, hard filling < 5 mm to hard, filling > 5 mm, slightly weathered, persistent < 1 mm, and aperture 0.1 mm | Damp to dry | Very favorable to favorable | 71.50 |
| Rating | 12 | 18 | 8 | 23 | 12.5 | −2 |
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| 2. Tunneling quality index (Q-system) |
| Average values of input parameters of RMR | Rock quality designation (RQD) | Joints number (Jn) | Joint roughness number (Jr) | Joint alteration (Ja) | Joint water reduction factor (Jw) | Stress reduction factor (SRF) | Q value |
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| Bore hole | Rock type |
| BH-1 at chainage 0 + 000 to 2 + 750 | Granite | 88 | Three joint sets plus random | Rough and irregular and undulating | Only surface staining with unaffected joint walls | Dry excavation | Low stress to medium stress | 12.57 |
| Rating | 88 | 12 | 3 | 1 | 1 | 1.75 | |
| BH-2 | Quartz schist | 50 | Two joint sets | Rough to slickensided undulating | Unaltered joint walls and surface staining only | Dry excavation | Low stress to medium stress | 21.95 |
| Rating | 50 | 4 | 2.11 | 1 | 1 | 1.23 |
| BH-3 | Calcareous quartzite | 80 | One joint set plus random | Rough and irregular and undulating | Unaltered joint walls to slightly altered joint walls having nonsoftening to silty- or sandy-clay coatings | Damp to dry | Low stress to medium stress | 20.49 |
| Rating | 80 | 3 | 3 | 2 | 0.83 | 1.62 |
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