Question:
In an opencast coal mine, blast vibrations are measured at two locations, A and B simultaneously for a maximum charge per delay (Q) of 1200 kg as given.Location Distance from the blast face, D (m) PPV (mm/s) A 100 112.5 B 300 20.3
\(PPV=K[\frac{D}{\sqrt{Q}}]^{-B}\)
where, K and ẞ are site constants. The PPV in mm/s, at a distance of 200 m from the blast face, is (round off up to 2 decimals)
In an opencast coal mine, blast vibrations are measured at two locations, A and B simultaneously for a maximum charge per delay (Q) of 1200 kg as given.
\(PPV=K[\frac{D}{\sqrt{Q}}]^{-B}\)
where, K and ẞ are site constants. The PPV in mm/s, at a distance of 200 m from the blast face, is (round off up to 2 decimals)
| Location | Distance from the blast face, D (m) | PPV (mm/s) |
| A | 100 | 112.5 |
| B | 300 | 20.3 |
where, K and ẞ are site constants. The PPV in mm/s, at a distance of 200 m from the blast face, is (round off up to 2 decimals)
Updated On: Sep 24, 2024
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Correct Answer: 37.5
Solution and Explanation
The correct answer is: 37.50 or 38.50 (approx)
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