What is RMR and RQD?
RQD is determined from rock cores or volumetric joint count; it is the percentage of rock cores in one meter of drill run. RMR is determined as an algebraic sum of ratings for all of the parameters.
What is difference between RMR and Q-system?
Weakness zones are characterized differently in the three systems. In the RMR, no special parameter is used; the Q applies a classification based on composition and depth of the zone; in the RMi the size of the zone is used.
What is the significance of RMR?
RMR combines the most significant geologic parameters of influence and represents them with one overall comprehensive index of rock mass quality, which is used for the design and construction of excavations in rock, such as tunnels, mines, slopes, and foundations.
How do you calculate the RMR of a rock?
The groundwater rating accounts for 15% of total ratings. The final RMR value of the rock is calculated as follows:(1) R M R = R 1 + R 2 + R 3 + R 4 + R 5 + R 6 where R1, R2, …, R6 are the ratings corresponding to six rock parameters as depicted in Table 2.
What is RQD soil investigation?
Rock quality designation (RQD) is a standard technique in the mining industry for the qualitative and quantitative assessment of rock quality and degree of jointing, fracturing, and shearing in a rock mass.
What is the value of RQD for sound rock?
Classification table
| RQD | Rock mass quality |
|---|---|
| <25% | Very poor |
| 25-50% | Poor |
| 51-75% | Fair |
| 76-90% | Good |
What is Q-system of rock mass classification?
The Q-system for rock mass classification is developed by Barton, Lien, and Lunde. It expresses the quality of the rock mass in the so-called Q-value, on which are based design and support recommendations for underground excavations.
What does a higher RMR mean?
A high resting metabolic rate means your metabolism is efficient, requiring more calories to achieve basic functions. While RMR is often interchanged with basal metabolic rate (BMR), it isn’t exactly the same.
Is a higher or lower RMR better?
Knowing your RMR can help you understand how many calories you need to function, plus what you need to intake (or not intake) to reach your health and wellness goals. Having a higher RMR means you will burn more calories at a state of rest (yep – just for doing nothing more than simply existing!)
How do you calculate the RQD of a rock?
Therefore, RQD = (640/1200)x100 = 53% which is fair quality rocks, i.e. rocks are moderately weathered.
What is value of good RQD?
75–90
7.2 Classification Parameters
| Rock Quality | RQD Index in % |
|---|---|
| Poor | 25–50 |
| Fair | 50–75 |
| Good | 75–90 |
| Excellent | 90–100 |
How do you calculate RQD?
What is RQD how it is related to the quality of the rock?
Rock Quality Designation (RQD) is a measure of quality of rock core taken from a borehole. RQD signifies the degree of jointing or fracture in a rock mass measured in percentage, where RQD of 75% or more shows good quality hard rock and less than 50% show low quality weathered rocks.
How do I calculate core recovery and RQD?
RQD is defined as the sum of the core samples having a length greater than 100mm divided by the total length considered. RQD value is calculated as a percentage value. Therefore, the above ration shall be multiply by 100. Let see how it is calculated in practice.
How is RQD calculated?
Why is RMR higher than BMR?
The key difference, while the BMR is based on being at rest for 24-hours, the RMR includes movement of light activities. These activities include eating, using the restroom, walking, stretching, etc. Since movement is included in the RMR, your resting metabolic rate will always be slightly higher than your BMR.
Why is my RMR so high?
“A person with a large liver can have a higher metabolic rate.” Differences in brain size can also play a role. Other significant contributors to RMR include body composition — a 140-pound person with 15 percent body fat will have a higher metabolic rate than a 140-pound person with 25 percent body fat — and age.
Is RMR and BMR the same?
Basal metabolic rate (BMR) is often used interchangeably with resting metabolic rate (RMR). While BMR is a minimum number of calories required for basic functions at rest, RMR — also called resting energy expenditure (REE) — is the number of calories that your body burns while it’s at rest.
What is RQD used for?
The Rock Quality Designation (RQD) index has been used for over 20 years as an index of rock quality. It measures the percentage of “good” rock within a borehole. It was developed by the senior author originally as a means of qualitatively describing whether a rock mass provided favorable tunneling conditions.
What is the rock quality designation (RQD)?
RQD stands for the rock quality designation and represents a rock mass classification system, based on the RQD index as a classification parameter for a quantitative estimation of the quality of rock mass.
How to compare the RMR Q and RMI classifications?
COMPARING THE RMR, Q, AND RMi CLASSIFICATION SYSTEMS Part 1: Combining the input parameters used in the three systems Reference: www.rockmass.net March 2008 7 B. DEGREE OF JOINTING input symbol RMR Q RMi B1. Rock quality designation (RQD) A2 = RQD = – Very good RQD = 90 – 100 a // value 20
What is the difference between RMR and Q-index?
A commonly used c orrelation between the RMR and the Q-index where deviations from the common correlation are shown. As seen, for Q = 1, RMR varies from less than 20 to 66. Note that the Q system applies logarithmic scale while RMR has a linear scale (revised after Bieniawski, 1976).
What is the RMR of rock mass quality?
CASE STUDIES OTHER CASE STUDIES INDIAN CASE STUDIES RMR = 9 ln Q + 44 Rock Mass Quality – Q R o c k M a s s R a t i n g R M R 100 80 60 40 20 0 0.001 0.01 0.1 1 10 100 1000 +50% -50% -25% +25% Common correlation Figure 1.