Which of the following is/are used to estimate the strength of a rock mass?
- API gravity
- Resistivity
- Kriging
- RQD
The Correct Option is D
Solution and Explanation
To determine the strength of a rock mass, various methods and metrics are used in geology. One of the prominent measures is the Rock Quality Designation (RQD).
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Understanding Rock Quality Designation (RQD):
- RQD is a measure of the quality of rock cores taken from a borehole, expressed as a percentage.
- It assesses the degree of jointing or fracturing in a rock mass.
- Higher RQD values (typically above 75%) indicate better rock quality and, correspondingly, that the rock mass is strong.
-
Comparison with Other Options:
- API Gravity:
- Related to the oil industry and measures the density of petroleum liquids relative to water. Not used for assessing rock strength.
- Resistivity:
- Primarily used in geophysics to determine subsurface characteristics, but not a direct measure of rock mass strength.
- Kriging:
- A geostatistical method used for interpolation and spatial analysis. It does not directly assess rock strength.
- API Gravity:
- Conclusion: Based on these analyses, RQD is the correct choice for estimating the strength of a rock mass, as it directly relates to the quality and integrity of the rock structure.
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