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1.
The hydrogeomechanical problems of mining are considered, which deal with rocks and ground water as a single mechanical system.
Among these problems are the openpits slopes stability, rocks consolidation and surface subsidence due to ground water level
lowering, water inrushes into mine workings, rock bursts prevention by using the water injection into the advance boreholes,
etc. The paper contains the basic theoretical grounds, as well as in-situ and laboratory methods for the investigation of
these processes.
The combined study of ground water regime and rock deformations has resulted in the theoretical substantiation of the hydrodynamic
and geomechanical processes within the scope of unique scientific direction-hydrogeomechanics (Mironenko, 1974). The hydrogeomechanical
models are widely used now for the analysis and forecasting the extremely important processes connected with the safe and
efficient mining operations, as well as with the protection of geological medium. Among these processes are:
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o deformations of the open-pit slopes and spoil dumps;
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o consolidation of rocks due to the ground-water pressure drop;
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o water-and-rock material inrushes into mine workings caused by deformations of the undermined rock mass;
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o geodynamical processes due to the changes in ground water regime;
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o artificial hydrofracturing in rocks;
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o transformations of clay linings under the tailing ponds and other technical water basins
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相似文献
2.
| 1. |
A new model is suggested with simple techniques representing the dynamic behavior of an assembled support system at intersections
of horizontal mine workings. Plastic behavior of the material at the conjugation points of structural elements is taken into
account.
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| 2. |
Equations systems are formulated to calculate the behavior of a support system sustaining static and dynamic rock pressures.
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| 3. |
In case of a dynamic impact upon the support system at a conjugation, the greatest strength is attained when the rigidity
of the external medium is higher than that of the medium filling the space between the support systems of the individual workings.
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| 4. |
When a plane wave acts upon the support system at the conjugation, the internal support system removed from the wavefront
at the initial time is especially susceptible to breakdown.
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| 5. |
Support systems interact not only in terms of vibration amplitude but also vibration frequency and form. The influence of
internal support systems upon the external support system is particularly strong.
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Institute of Mathematics and Mechanics, Academy of Sciences of the Kazak SSSR, Alma-Ata. Translated from Fiziko-Tekhnicheskie
Problemy Razrabotki Poleznykh Iskopaemykh, No. 3, pp. 6–12, May–June, 1990. 相似文献
4.
| 1. |
Cavity elimination technology by isolation and filling with low-strength materials has been used successfully in working mineral
resources by underground mines, including beds of complex structure.
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| 2. |
The technicoeconomic and social effectiveness of cavity elimination that preserves the surface of the earth and the environmental
setting in the area surrounding the mines and the utilization of production wastes and low-quality local mineral resources
endow these technologies with a conservation-oriented value and open new prospects for their use.
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| 3. |
Scientific and engineering principles of resource-saving cavity elimination technologies and years of practical experience
with them should be considered by designers of plans for development of new deposits in mining fields across the country.
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| 4. |
Tested methods of material quality improvement are recommended for large-scale introduction in mining and related industries:
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disintegrator processes of material grinding and activation;
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vibration equipment for sorting, triturating, and transporting granular and fluid mixtures; and
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electrochemical water treatment with membrane technologies.
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5.
Pre-cementation or pre-grouting of deep shafts in South Africa is an established technique to improve safety and reduce water
ingress during shaft sinking. The recent completion of several pre-cementation projects for shafts deeper than 1000m has once
again highlighted the effectiveness of pre-grouting of shafts utilizing deep slimline boreholes and incorporating wireline
technique for drilling and conventional deep borehole grouting techniques for pre-cementation.
Pre-cementation of deep shaft will:
| (i) |
Increase the safety of shaft sinking operation
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| (ii) |
Minimize water and gas inflow during shaft sinking
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| (iii) |
Minimize the time lost due to additional grouting operations during sinking of the shaft and hence minimize costly delays
and standing time of shaft sinking crews and equipment.
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| (iv) |
Provide detailed information of the geology of the proposed shaft site. Informations on anomalies, dykes, faults as well as
reef (gold bearing conglomerates) intersections can be obtained from the evaluation of cores of the pre-cementation boreholes.
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| (v) |
Provide improved rock strength for excavations in the immediate vicinity of the shaft area.
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6.
During the 1990s, passive treatment technology was introduced to the United Kingdom (UK). Early hesitancy on the part of regulators
and practitioners was rapidly overcome, at least for net-alkaline mine waters, so that passive treatment is now the technology
of choice for the long-term remediation of such discharges, wherever land availability is not unduly limiting. Six types of
passive systems are now being used in the UK for mine water treatment:
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♦ aerobic, surface flow wetlands (reed-beds);
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♦ anaerobic, compost wetlands with significant surface flow;
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♦ mixed compost/limestone systems, with predominatly subsurface flow (so-calledReducing andAlkalinityProducingSystems (RAPS));
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♦ subsurface reactive barriers to treat acidic, metalliferous ground waters;
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♦ closed-system limestone dissolution systems for zinc removal from alkaline waters;
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♦ roughing filters for treating ferruginous mine waters where land availability is limited.
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Each of these technologies is appropriate for a different kind of mine water, or for specific hydraulic circumstances. The
degree to which each type of system can be considered “proven technology” corresponds to the order in which they are listed
above. Many of these passive systems have become foci for detailed scientific research, as part of a $1.5M European Commission
project running from 2000 to 2003. 相似文献
7.
Conclusions
| 1. |
The possibility of tracking the trajectory of a pneumatic punch by recording oscillations of the ground excited by the shock
pulses has been experimentally confirmed.
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| 2. |
To determine the motion of a pneumatic punch in a horizontal plane, one receiver of seismoacoustic oscillations must be installed
at the point to which the punch is headed, with two others in symmetric positions to the left and right.
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It remains to thank V. N. Oparin for initial consultations and A. D. Kostylev and B. N. Smolyanitskii for practical assistance
in the work.
Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirsk. Translated from Fiziko-Tekhnicheskie Problemy
Razrabotki Poleznykh Iskopaemykh, No. 4, pp. 117–121, July–August, 1998. 相似文献
8.
| 1. |
The technical parameters of coals of the grades K and K2 have been studied during working of the excavation pillar by eastern long-wall faces 4 and 5.
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| 2. |
Statistical characteristics of variation series were obtained.
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| 3. |
Maps of isolines representing the “principal relief forms” have been compiled, which describe the regularities of distribution
of the technical parameters.
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| 4. |
The variations of these parameters were examined in three directions relative to the axis of the well used for multiple hydraulic
treatment of a predegassed seam.
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Moscow Institute of Mining. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Polyznykh Iskopaemykh, No. 6, pp. 84–91,
November–December, 1990. 相似文献
9.
| 1. |
The sufficiently high reliability of the standard (k-ε) model for the Reynolds-stress in calculating the velocity field in
plane chamber-like mine workings has been demonstrated.
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| 2. |
A version of the velocity-field calculation in plane chambers by the Smagorinskii model has been proposed, using the (k-ε)
model in the preliminary stage, so as to permit considerable reduction in computer time.
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| 3. |
The most rational finite-difference schemes for approximation of the advection term in the turbulent-diffusion equation when
estimating the air transfer in plane chamber-like workings have been recommended:
| a) |
for periodically acting localized sources of impurity ejection, scheme VII (Table 2);
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for discharge emissions of harmful impurities, scheme VI (Table 2).
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It is shown that scheme V (Table 2) has high schematic viscosity in a nonuniform velocity field, and therefore cannot be used
to calculate flows in chambers with complex geometry.
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| 5. |
Using the numerical modeling of the physical fields (air velocity and impurity concentration) in a ventilated volume proposed
here permits the determination either of the time to achieve the maximum permissible concentration with specified contamination-source
intensities and air flow rates or the air flow rate required in a specified ventilation time.
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S. M. Kirov Mining Institute, Academy of Sciences of the USSR, Kazan’ Branch, Apatity. Translated from Fiziko-Tekhnicheskie
Problemy Razrabotki Poleznykh Iskopaemykh, No. 1, pp. 74–88, January–February, 1990. 相似文献
10.
| 1. |
The distribution of lumps by mass is a complementary structural-statistical lumpiness characteristic that makes it possible
to ascertain more clearly certain laws governing the process of fragment formation as compared with the distribution of lumps
by size.
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| 2. |
A Weibull-type equation provides good approximation of unimodal curves of mass distribution for the different conditions considered
for the multiple fracture of rigid bodies.
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| 3. |
There are characteristic points about which values of the distribution-shape parameter are grouped: the shape parameter is
close to 1/3 for the impact failure of lumps and the crushing of specimens, and to 1/2 for the case of explosive crushing.
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| 4. |
An increasing in the end surcharge of tubular rock specimens failed by blasting leads to a reduction in the shape parameter
for the fine fractions and to diminution of the bimodality effect.
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| 5. |
Use of the operation of the additional opening of blast-induced cracks in weakened lumps of semimetallic ore is reflected
in geometrically similar transformations of the distribution curves in the direction of a reduction in lump mass.
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| 6. |
As applies to the blast-induced failure of brittle plates, a functional relationship between the mass of the fragments and
the reduced distance to the blast center is obtained by statistical averaging; for small values of the argument, the latter
is approximated by the fourth power of the reduced distance.
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I. I. Polzunov Branch of the Altai Polytechnic Institute, Biisk. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki
Poleznykh Iskopaemykh, No. 1, pp. 34–38, January–February, 1989. 相似文献
11.
| 1. |
With low-temperature plasma it is possible to create facings in soft rocks covering the entire working perimeter in a short
period of time.
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Field tests of facing models show them to have a sufficient carrying capacity and resistance to dynamic as well as static
loads.
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Laboratory tests of specimens from thermally reinforced clay rocks determined the dynamics of the variation of their strenth
characteristics as a function of the speed of loading.
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Military Engineering Academy, Togliatti. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No.
2, pp. 74–78, March–April, 1989. 相似文献
12.
Conclusions The following characteristics of self-transportation have been established.
| 1. |
If the frictional force F does not exceed the recoil force within a single oscillation period T of the vibrational device,
the phase length of forward motion in steady self-transportation is always half the period; it only becomes less than half
the period when the relationship between these forces reverses. In the vicinity of the point where this relationship reverses,
the rate of self-transportation of the device is a maximum.
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| 2. |
If the preimpact momentum of a device operating in vibroshock conditions is less than the critical value i=FT/4, self-transportation
is always in the opposite direction to the shocks.
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The greatest rate of self-transportation that is theoretically possible is equal to the critical momentum i of the system
divided by the mass of the base element.
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| 4. |
The rate of self-transportation depends on the form of the momentum diagram of the resultant of the internal active forces
acting on the base mass. The character of the dependence and the relevant criteria are analogous to those established in evaluating
the ability of the form factor to reduce the vibration and the necessary input force for shock machines.
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These results offer the possibility of further analysis of self-transportation, taking the characteristics of the specific
generator of the internal active forces into account.
Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirsk. Translated from Fiziko-Tekhnicheskie Problemy
Razrabotki Poleznykh Iskopaemykh, No. 6, pp. 59–65, November–October, 1997. 相似文献
13.
Conclusions
| 1. |
The ultimate size of bubbles in a flotation cell is an outcome of competing processes: coalescence of bubbles and adsorption
of the surfactant on their surface.
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| 2. |
Formation of highly developed initial interface due to breakup of the gas phase is an indispensable condition for stabilizing
bubble size at a lower size level.
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| 3. |
The optimal method of frothing agent injection (for stabilizing bubble size) into the flotation cell is to inject it into
the air phase as vapors or aerosols.
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Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirsk. Translated from Fiziko-Tekhnicheskie Problemy
Razrabotki Poleznykh Iskopaemykh, Vol. 34, No. 3, pp.101–107, May–June, 1998. 相似文献
14.
Conclusions
| 1. |
An approach to shock contact-strength (SCS) evaluation is proposed that allows, on the basis of the instrument package developed,
fairly rapid measurement of the pertinent strength characteristics of rocks in borenhole and blasthole sections.
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Laboratory and field test data have revealed a pronounced statistical link of the SCS data with several well-known parameters
and features of the mechanical properties of rocks.
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The proposed method can be employed most efficiently in those cases where core test data are not available at all or are available
partially, in particular for assessing strength of rocks in blastholes as well as in engineering and geological drill holes
when the yield of core suitable for mechanical tests is low. If there are appropriate grounds, the method may be applied for
petrographic zonation of rocks and delineation of productive areas.
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In view of the complicated mechanism of stress pulse generation at the SCS sensor output (dependence on the moduli of elasticity
and deformation, piezoelectric transducer conversion function, design of the shock device, etc.), the functions of the relationship
of SCS signals with specific features of the mechanical properties of rocks should be determined by the correlations analysis
method. The stability of the mechanoelectrical conversion factor may be monitored with the help of samples specially prepared
from homogeneous materials (concrete, duralumin, epoxy compounds, etc.).
Institute of Geophysics, Ural Branch, Russian Academy of Sciences, Ekaterinburg. Translated from Fiziko-Tekhnicheskie Problemy
Razrabotki Poleznykh Iskopaemykh, Vol. 34, No. 2, pp. 24–30, March–April, 1998. 相似文献
15.
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Electromechanical regime observations in North Ural bauxite deposits can be used to evaluate the transcritical strain in rocks,
such as loosening or pillar breakage under long-term loads.
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In conditions where no discontinuities of rocks in the peripheral zone of workings are observed, electrometric technology
can evaluate moisture content variations.
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With the existing technology, it is impossible to estimte elastic strain by electrometric measurements in North Ural bauxite
deposits.
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Ural Scientific-Research Institute of Copper Production, Sverdlovsk. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki
Poleznykh Iskopaemykh, No. 6, pp. 92–98, November–December, 1989. 相似文献
16.
Conclusions The prospect of switch-over of the industry to processing lean materials raises the problem of beneficiation of finely disperse
placers of noble metals, the profitability of realization of which lies in raising the efficiency of separation processes
by reducing frictional forces in the course of implementation of the technological processes and by employing modern technologies
for beneficiation. The engineering—technological solutions worked out are distinguished by ecological safety during implementation
of the beneficiation processes.
The proposed schemes of beneficiation and primary processing of finely disperse minerals may be used:
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- for enhancing profitability of utilization of currently exploited placers of noble metals;
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- for reviewing economic effectiveness of technologically unprofitable coastal-marine placers in which finely disperse fractions
of useful components are prevalent;
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- for reprocessing of rejects of previously processed placers;
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- for recovery of platinoids and gold from bedrocks.
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Scientific Research Center, Far Eastern Branch, Russian Academy of Sciences, Petropavlovsk-Kamchatskii. Translated from Fiziko-Tekhnicheskie
Problemy Razrabotki Poleznykh Iskopaemykh, Vol. 34, No. 3, pp. 108–113, May–June, 1998. 相似文献
17.
| 1. |
The authors show the dependence of the electrochemical properties of magnetite on the thickness of the layer removed from
the specimen surface; this is of scientific interest, because the results obtained enable one to determine the effective conditions
for preparation of solid electrolytes and to refine the experimental procedure so as to obtain reproducible data.
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| 2. |
The variation of the magnetite electrode potential with the pH of the medium practically follows the same pattern as that
characterizing magnetite-hematite equilibrium.
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| 3. |
Addition of sodium oleate shifts the electrode potential toward the more negative region as a result of adsorption of the
flotation reagent, the maximum change in potential being observed at pH 6–7, which also corresponds to maximum flotability
of magnetite.
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相似文献
18.
| 1. |
In a conveyer-hopper system of underground coal mine transport a load stream can be represented by a vector Γ6 comprised of six linearly independent parameters:
, qΠ, σΠ, qmax, σK and tΠ.
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| 2. |
An analytic model has been developed describing the transformation of load streams, which allows defining the parameters of
the vector Γ6 in an arbitrary cross-section of a conveyer-hopper system. It helps improve the accuracy of process evaluations for under-ground
transport system.
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| 3. |
At an arbitrary cross-section of the conveyer-hopper system, load streams can be described by a Markov step process. This
provides a uniform framework for study of load stream transformations.
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| 4. |
The length of periods of load stream arrival and stream absence conform to an exponential distribution. The intensity of transformed
load streams follows a normal distribution in a portion of the arrival period.
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| 5. |
A good convergence has been established between the results of calculations of the maximum composite load stream and normative
data obtained from a computer simulation study.
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Donetsk Coal Institute, Donetsk. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 6, pp.
71–77, November–December, 1989. 相似文献
19.
| 1. |
By analyzing the formation of brines in underground leaching chambers, it is shown that the general criterial dependence representing
this process includes the criteria Pz, Ku, and the geometrical simplex D/h.
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| 2. |
The authors determine the conditions of similarity for modeling the processes of brine formation in underground leaching chambers
by means of specimens of core material.
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相似文献
20.
| 1. |
The equation of bit rotation in anisotropic rock allows the difference in directions of the bit axis and the borehole axis
(the tangent ot the trajectory) to be determined.
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| 2. |
The asymptotic approach here proposed allows the curvature and the normal to the trajectory with a specified direction of
the borehole axis at the face to be determined for weakly deviated borehole trajectories. The equations of the borehole trajectory
are thus determined.
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| 3. |
Combined numerical calculation of the column equilibrium and the borehole deviation is unnecessary in the new method of describing
the characteristics of the drilling-column base; instead, the solution is obtained by taking account of just a few simple
parameters of the column base, determined separately by solving the problem of elastic deformation of the base of a heavy
drilling column in a distorted inclined shaft.
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| 4. |
The formulas for the curvatures and components of the normal to the borehole trajectory obtained for the case of gyrotropic
rock describe the locally independent distortion of the projection of the borehole trajectory in two planes orthogonal to
the bed, one of which includes the bit axis.
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Paper 1667 deposited at VNIIOENG, Moscow, 1988. 相似文献
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