What is the meaning of Q-system?
The Q-system is a classification system for rock masses with respect to stability of underground openings. Based on estimation of six rock mass parameters, a Q-value for a rock mass can be calculated. This value gives a description of the rock mass quality.
What are the parameters for Q-system?
Effectiveness of Grouting
| S. No. | Engineering parameters | Before grouting |
|---|---|---|
| 1 | Rock mass quality Q | 0.8 (very poor) |
| 2 | Normalized rock mass quality Qc | 0.4 |
| 3 | Modulus of deformation Ed in GPa | 7 |
| 4 | P-wave velocity Vp in km/sec | 3.1 |
What is quality RMR?
The rock mass rating (RMR) is a geomechanical classification system for rocks, developed by Z. T. Bieniawski between 1972 and 1973. Since then it has undergone multiple modifications out of which, RMR89 is commonly used.
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.
How is SRF calculated?
Ratings for SRF are given in Table 8.6….Stress Reduction Factor.
| Conditions | SRF | |
|---|---|---|
| (a) Weakness zones intersecting excavation, which may cause loosening of rock mass when tunnel is excavated | ||
| B | Single-weakness zones containing clay or chemically disintegrated rock (depth of excavation ≤50 m) | 5.0 |
What is RMR and Q system?
Although the rating methods of RMR and Q-system are additive and multiplicative, respectively, the basic concepts of both schemes are similar. Both schemes allocate the ratings to the properties that influence the rock mass behavior and then quantitative figures such as total-RMR and Q-value are produced.
What is difference between RMR and Q system?
How do you calculate RMR in geology?
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 inductor Q?
The quality factor (or Q) of an inductor is the ratio of its inductive reactance to its resistance at a given frequency, and is a measure of its efficiency. The higher the Q factor of the inductor, the closer it approaches the behavior of an ideal inductor.
What is SRF for inductors?
The self resonant frequency of an inductor is the frequency at which the parasitic capacitance of the inductor resonates with the ideal inductance of the inductor resulting in an extremely high impedance. At this frequency the device looks like an open circuit.
What does Q mean in electricity?
charge
In physics, charge, also known as electric charge, electrical charge, or electrostatic charge and symbolized q, is a characteristic of a unit of matter that expresses the extent to which it has more or fewer electrons than protons.
What is Q factor in electronic?
The quality factor or Q factor is a measure of the performance of a coil, capacitor inductor in terms of its losses and resonator bandwidth. Simple formulas can relate the variables. The quality factor or ‘Q’ of an inductor or tuned circuit is often used to give an indication of its performance in a resonator circuit.