Assessment of abrasivity by physico-mechanical properties of rocks

The paper describes a new estimation method for rock abrasivity as a function of grain size, porosity, rock-forming mineral hardness, structural bond strength and humidity. The cumulative effect of these properties on the rock abrasive ability is represented as a sum of dimensionless indexes in the canonical structural-hierarchical scale. __________ Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 3, pp. 46–57, May–June, 2009     

Effect of dilation on rock breaking by explosion of a cylindrical charge

A calculation model is suggested for describing the breaking effect of the explosion of a cylindrical charge in a rock mass. It is shown that consideration of dilation of the broken rock and its compressibility in the elastic zone affects essentially the calculated values of breaking parameters. Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirsk. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 4, pp. 75–83, July–August, 1999.     

Estimation of duration of electromagnetic-radiation signals in rock failure

The criterion and procedure of determining the duration of the electromagnetic-radiation signals of rock samples in various stages of loading are proposed. Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirsk. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 4, pp. 61–65, July–August, 1999.     

Estimation of rock resistance to hydraulic fracturing from data of laboratory investigations

Conditions of carrying out laboratory investigations are examined, and calculated formulas are presented for determination of rock resistance to hydraulic fracturing. Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 3, pp. 17–23, May–June, 2000.     

Model of the effects of an explosion in a well

Conclusions A new model of explosions in wells was proposed on the basis of the "inverse" (in terms of the factor of rock pressure) zonal disintegration of rocks around underground workings (Discovery No. 400) and the anomalously low friction in block media detected experimentally by the authors in an investigation of pendulum-type waves. Considerable weight was given to the empirical finding that for certain energies of shock loading of models of block media, friction "vanishes" between interacting blocks of geologic materials in directions orthogonal to the line of action of the external impulse. The geometric parameters of the quasi-cylindrical system of blocks formed around an exploded well are determined by the scale factor of the zonal disintegration process, this factor being linked to the radius of the well; the dynamic—kinematic characteristics of geologic blocks capable of moving along the annular "inverse" disintegration zones are determined by the type of stress state of the surrounding rock masses. Institute of Mining, Siberian Branch of the Russian Academy of Sciences, Novosibirsk. Translated from Fiziko—Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 2, pp. 37–46, March–April, 1997.     

Effect of geological disturbances on the danger of rock bursts in a rock mass

Results are given for investigation of the effect of geological disturbances on the danger of rock burst in a rock mass during preparation and mining of operating blocks. Nature of the distribution of dynamic phenomena and the specific electrical resistance in the rock mass in regions of tectonic dislocations with a specific order of carrying out mining work are established which makes it possible to evaluate the efficiency of ore extraction technology. Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirsk. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 1, pp. 14–20, January–February, 1999.     

Stress state of a rock mass in the vicinity of seam containing a working. Three-dimensional problem

Formulas are obtained to determine the stresses at any point of a rock mass. The formulas are derived through double integrals of an auxiliary function represented by a convergent Neumann series. Approximations of the kernels are presented by algebraic combinations of elementary functions. Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirsk. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 5, pp. 35–41, September–October, 1999.     

Gradient approach to rock strength estimation

The possibility of application of the gradient approach to rock strength estimation is considered in the case when the mechanical properties of the rocks change as a result of stress concentration close to rock structure defects, cavities, and mine workings. A criterion of shear crack appearance is proposed, and expressions for the critical stresses are obtained. Institute of Mining of the North, Siberian Branch, Russian Academy of Sciences, Yakutsk. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 4, pp. 54–60, July–August, 1999.     

Problems of nonlinear geomechanics. Part 1

In the study, an attempt is made to present the most important results of experimental researches on nonlinear geomechanics—a rapidly developing scientific trend in recent years—from single positions within the framework of Academician M. A. Sadovsky's concept relative to the block-hierarchical structure of rock masses. The key role of the linear embedment coefficient of geoblocks for contiguous hierarchical levels, and the statistical characteristic of the average distances between the edges of cracks separating the structural blocks between themselves to the diameters of these blocks, as well as the scale factor of the phenomenon of the zonal disintegration of rocks around underground workings is demonstrated in the development of nonlinear geomechanical processes at various hicrarchical levels: from monatomic-crystalline to planetary scale. A number of major scientific problems, a solution of which demands particular attention of experimenters and theoreticians is formulated. The circle of problems touched upon in this part of the article concerns primarily the analysis of nonlinear quasi-static processes. Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirks. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 3, pp. 12–26, May–June, 1999.     

Comparison of rock mass classification systems

The paper presents the comparison of the most widely-applied rock-mass classifications RMR and Q and a system developed by VNIMI in Russia. It has been shown that the results obtained from using these systems for the forecast of rock mass stability and selection of support types enjoy a satisfactory conformity. __________ Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 4, pp. 71–75, July–August, 2007.     

On the structure of electromagnetic-radiation signals and their association with acts of rock-specimen failure

Results are presented for experimental investigations of features of the electromagnetic radiation of rock specimens in various stages of loading, which make it possible to judge events (acts) involving loss of continuity in geomaterials with respect to the structure of the electromagnetic pulses. Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 1, pp. 5–11, January–February, 2000.     

The system of probable-temporal models of block mass dynamics

A system of interacting simulational and analytical models adequately describing the dynamic behavior of rock of hierarchical block structure is considered. This system yields a broad spectrum of dynamic characteristics of the rock, such as the probability distribution and mathematical expectations of block residence time in the consolidated state, the mean intensities of elastic energy surges in the rock, and the combined probability distribution of consolidated and unconsolidated states of a fixed set of blocks. Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 3, pp. 42–53, May–June, 2000.     

Rockburst-hazard criterion of rock mass

Technological operations employed in preparing blocks for mining by the induced block-caving system are investigated. An estimate is given for the stress-strain state of the mass, and a rockburst-hazart criterion of deposit adopted as the ratio of the seismic energy accumulated in the rock mass to the potential energy contained in the explosion of charge is substantiated. Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirsk. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 6, pp. 44–47, November–December, 1999.     

Control of longitudinal hydraulic fracturing of wells

An analytical solution is presented for the problem of the hydraulic fracturing of a rock mass by radial cracks. The possibility of controlling longitudinal hydraulic fracturing by creating an initiating slit and uniaxial loading of the walls of a borehole is analyzed. An example is described for the synchronous hydraulic fracturing of a system of parallel boreholes to form a horizontal cavity for an electrohydraulic source of vibration. Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirsk. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 5, pp. 3–12, September–October, 1999.     

Effect of stemming on rock breaking with explosion of a cylindrical charge

A calculation scheme is developed for the destroying action of explosion of a borehole charge in a brittle medium taking account of the ejection of stemming material and outflow of detonation product gases. The influence of different rock and explosive parameters on the efficiency of stemming application is studied. Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirsk. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 5, pp. 42–52, September–October, 1999.     

An approach to development of an information geomechanical structural model of the Kuznetsk coal basin

The geographic information system designed at the Institute of Coal and Coal Chemistry for the Kuznetsk Coal Basin and the non-linear geomechanics researches undertaken at the Institute of Mining has served the basis for analyzing the hierarchical structure of geological faults in the Anzherskiy economic district (Kemerovo Region). The analysis is performed by a new canonical scale for structural-hierarchical representations with base , where A and x are the normalized functionally related values). The recommendations are given on how to utilize the geoinformation system of the Kuznetsk Coal Basin in order to obtain a graphical-analytical representation and a system analysis of experimental geomechanical data. __________ Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 3, pp. 27–49 May–June, 2006.     

Oriented hydraulic fracturing of a mass of rocks enclosing the "international" diamond pipe

Conclusions  1. Whereas in previous works oriented hydraulic fracturing was carried out at a maximum depth of 450 m, in the present work the depth was 780 m. 2. Oriented hydraulic fracturing was effected in two types of sedimentary rocks. The maximum water pressure confined to the instant of shifting and passing of the initiating slit into an extended slit was 24 MPa for rock salt and 26 MPa for dolomite anhydrites. 3. The calculated and experimental maximum pressure data were in good agreement. Divergences for rock salt and dolomite anhydrites were 9.5 and 11%, respectively. 4. The technology and technical facilities developed by the Institute of Mining, Siberian Branch, Russian Academy of Sciences for creating oriented hydraulic fracture were proved to be efficient in new, more complicated situations. 5. Creation of extended slits through boreholes made it possible to achieve the set goal, i.e., to detect oil and gas shows in rock masses enclosing diamond-bearing kimberlite pipe. It is recommended that underground mining operations be carried out by using borehole-slit technique as a method for prospecting these hazardous sites. Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirsk. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, Vol. 33, No. 6, pp. 105–109, November–December, 1997.     

Determination of the filtration properties and stresses in a coal seam by solving the inverse problem

A method is proposed for determining the diffusion coefficient in a coal seam and the horizontal stresses in the enclosing rock on the basis of an algorithm which involves the solution of a class of inverse parabolic problems for regions with a moving boundary. The initial data is the change in gas pressure in a plugged-up borehole. Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 2, pp. 15–22, March–April, 2000.     

Calculation of the stress state of a rock mass using in-situ data on depormation

The stress-strain state of three basic problems of elasticity theory is investigated for any part of a rock mass modeled by a half-plane. An integral relation is established between the stress and displacement components of the boundary of the half-plane. This makes it possible to obtain all components in explicit form through the boundary conditions. These results permit use of in-situ stress and/or displacement measurements to restore deformation in the half-plane. Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirsk. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No 3, pp. 27–35, May–June, 1999     

Determination of the region of vibroseismic action on an oil deposit from the daylight surface

The effect of the dimensions of the zone of vibroseismic action on the development of an oil field from the daylight surface is first proved and evaluated on the basis of experimental data. The dominant role of the horizontal component of rock vibrations is demonstrated in the process. Factors governing the irregular character of formation reaction to vibroseismic treatment are analyzed. Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirsk. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 4, pp. 3–11, July–August, 1999.