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Date submitted2003-06-19
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Date accepted2003-07-30
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Date published2004-09-09
Parametric support for calculations of long-term stability of structures during construction and reconstruction of buildings in the territory of development of weak water-saturated sandy-clay sediments
- Authors:
- R. E. Dashko
- A. V. Shidlovskaya
The main leading factors (changes in the stress state of rocks at the base of structures, physico-chemical and biochemical conditions) determining the long-term stability of surface structures are analyzed. It is noted that filtration consolidation is not of practical importance when considering the compressibility of rocks. The influence of physico-chemical factors on sandy-clayey rocks is evident when polluted by runoff with a wide range of mineralization and composition. The effect of intensification of microbial activity, during which biochemical gases are formed and the increase in the content of bacterial mass, on reducing the strength and deformation capacity of clayey rocks is particularly emphasized. It was found that the transformed clay rocks are usually characterized by the presence of quasi-plastic state.
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Date submitted2003-06-24
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Date accepted2003-07-01
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Date published2004-09-09
Influence of the construction protective coating on the stress and strain state of the ore rock massif
- Authors:
- D. A. Potemkin
The regularities of the formation of the vault displacement during the construction of mine workings of the protective slab.
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Date submitted2003-06-03
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Date accepted2003-07-10
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Date published2004-09-09
Estimation of deformation and strength characteristics of the tunnel's host rocks by seismic data
- Authors:
- O. V. Boiko
The obtained dependencies between the values of deformation-strength characteristics of host rocks for the North-Muisk Tunnel obtained from seismic data and geological parameters recorded during tunneling by the coefficient of hardness of rocks on the Protodyakonov scale for granites of different composition are presented.
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Date submitted2003-06-01
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Date accepted2003-07-17
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Date published2004-09-09
Specific features of well construction in conditions of inelastic deformation of salt deposits
- Authors:
- N. I. Slyusarev
- S. P. Mozer
- R. A. Ibraev
The issues of drilling and construction of wells under unequal components of rock pressure in saline sediments are considered. The main factors that reduce the stability of the wellbore are given. Reflects the issues associated with the choice of the type of drilling fluid to exclude harmful manifestations of rock pressure.
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Date submitted2003-06-25
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Date accepted2003-07-24
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Date published2004-09-09
Manifestation of rock pressure in the capital and preparatory workings in the saline rocks of the Internatsionalny mine
The results of field observations of displacements of salt-bearing rocks of the Charskaya Formation in the vicinity of mine workings at the underground Internationalny mine, as well as tests of rock samples are presented. The causes of negative deformation processes in the mine workings support are outlined.
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Date submitted2003-06-01
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Date accepted2003-07-10
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Date published2004-09-09
Methodology for evaluating the stability of viscoplastic rocks in the walls of deep wells
- Authors:
- L. K. Gorshkov
- V. G. Gorelikov
Stability of viscoplastic rocks (clays, salts, ice) in the walls of deep wells can be evaluated based on the theory of aging (steady-state creep), for which we propose a proven in practice methodology for determining the stresses on the contour of the wellbore section, radial displacements of points on this contour and their speed.
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Date submitted2003-06-22
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Date accepted2003-07-06
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Date published2004-09-09
Designing parameters of drilling fluids and flushing regimes during well drilling
- Authors:
- I. E. Dolgii
The results of studies on the development of parameters of drilling fluids and flushing modes when drilling vertical, deviated and horizontal wells, as well as the methodology for determining the optimal parameters of drilling fluids and drilling modes are presented.
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Date submitted2003-06-16
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Date accepted2003-07-30
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Date published2004-09-09
Determination of the rational length of horizontal transport excavations of underground structures
- Authors:
- V. N. Makishin
- Yu. A. Zudikhin
The influence of natural conditions and design parameters of underground economic structures built in mountainous terrain on the length of their horizontal transport excavations has been studied. The method of determining the length of tunnels taking into account the terrain relief and the height of technological chambers is considered.
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Date submitted2003-06-12
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Date accepted2003-07-13
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Date published2004-09-09
Specific features of rock mass deformation around excavations, taking into account their anisotropy
- Authors:
- I. E. Dolgii
- D. I. Raevskii
- A. A. Silantev
The methods of determining the parameters of anisotropy of rocks, containing mine workings, the nature of the deformation of rocks in the contour zone during elastic-plastic deformation are shown. The issues of determining the shapes and sizes of inelastic deformation zones depending on the physical and mechanical properties of rocks, the depth of mine workings and the size of the cross-sectional section are considered.
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Date submitted2003-06-11
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Date accepted2003-07-02
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Date published2004-09-09
Improving the efficiency of construction of conjunctions of capital mine workings through the use of anchoring
- Authors:
- E. V. Kiteleva
- V. V. Pershin
On the basis of the analysis of the used types of anchor supports and calculation of their parameters the advanced technology of capital mine workings conjugations construction is developed and the field of its application is substantiated. By the example of construction of one of the conjunctions of Raspadskaya mine the technical and economic efficiency of the developed technological schemes is shown.
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Date submitted2003-06-09
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Date accepted2003-07-07
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Date published2004-09-09
Geomechanical substantiation of parameters for potash ore follow-up extraction from pillars using a drill auger excavation
On the example of Starobinskoye deposit the criteria determining the choice of development systems and possible ways to increase the extraction of potassium reservoirs are considered. Different principal schemes of sylvinite extraction from pillars by auger drilling technology are proposed. The method of geomechanical justification of the parameters of pillar extraction is developed. The results of the estimation of the stress-strain state (STS) of pillars and their host massif for the characteristic time moments of the pillar delineation of mined-out spaces are given.
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Date submitted2003-06-01
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Date accepted2003-07-23
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Date published2004-09-09
Geomechanical analysis of St. Petersburg bedrock clays as a fractured-block environment
- Authors:
- R. E. Dashko
- A. V. Volkova
The features of the structure of the St. Petersburg bedrock clay massif as a fractured-block environment are considered. The genesis of fracture formation due to tectonic and non-tectonic factors is analyzed, the zoning structure of the clay strata along the depth of the section, which is determined by the block size and the range of humidity and density changes. The regularities of changes in the parameters of shear resistance and general deformation modulus of clays by depth, as well as the influence of the scale effect on the same parameters of mechanical properties, are presented.
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Date submitted2003-06-08
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Date accepted2003-07-26
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Date published2004-09-09
Calculation of the parameters of artificial pillars in the ascending order of deposit mining
- Authors:
- D. Yu. Minaev
- E. I. Boguslavskii
The stress state of artificial monolithic pillars under the combined system of field development, which is affected by the rock pressure of hanging wall rocks and the active pressure of loose rock filling located in the chamber of the 2nd stage, was analyzed. As a result of calculations the optimum length of of the 1st stage chamber is 8 m, length of the 2nd stage II chamber is 40 m, hardening deposit strength is 3 MPa.
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Date submitted2003-06-07
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Date accepted2003-07-30
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Date published2004-09-09
Influence of depth on the stability of brine chambers, laid on the dome-type fields
- Authors:
- S. A. Tolstunov
- S. P. Mozer
The issues of laying of chambers on the brine fields of great depths are considered. The factors that have a favorable impact on the stability of underground dissolution chambers have been revealed. It is proposed to develop the reserves of dome-type deposits from depths of more than 2500 m.
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Date submitted2003-06-10
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Date accepted2003-07-12
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Date published2004-09-09
Geomechanical justification of rock mass model for the analysis of the limit state of pillars
An algorithm for selecting a mathematical model of the rock massif is presented. The finite difference method is used as a numerical solution method. The case of nonlinear rock deformation process is considered.
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Date submitted2003-06-28
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Date accepted2003-07-28
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Date published2004-09-09
Improvement of technological schemes of excavation areas in the development of high-gas-bearing coal seams at great depths
- Authors:
- A. V. Montikov
- A. P. Gospodarikov
- B. V. Bokii
The modern coal mines work at great depths, characterized by high natural gas content of the massif, which increases the intensity of gas release at high rates of movement of the working faces. A brief review of the experience of operating coal mines at great depths is given. The main directions of improvement of technological schemes of mine working areas are proposed.
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Date submitted2003-06-18
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Date accepted2003-07-13
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Date published2004-09-09
Evaluation of the influence of the blast pulse on the parameters of the blast funnel
- Authors:
- G. P. Zileev
- A. G. Zileev
The influence of the duration of the explosive pulse on the size of the resulting crater is investigated. Various factors affecting its size are considered. For this purpose, experiments were carried out at the mines of AO Sevuralboksitruda. It is established that the radius of the explosive funnel is equal to the radius of distribution of a wave of stresses for the duration of an explosive load, defined depending on the point of initiation of a charge, and cannot exceed the size of the radius of a cracking zone at influence on a monolithic rock massif by energy of explosion of an elongated charge. The minimum length of the charge, providing the maximum possible size of the blast funnel radius, depends on the initiation scheme, the detonation rate of the explosive used, physical and mechanical properties of rocks of the blasted massif and is determined by the obtained formulas.
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Date submitted2003-06-08
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Date accepted2003-07-12
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Date published2004-09-09
Recommendations for investment feasibility studies in the design of geothermal power plants
- Authors:
- E. I. Boguslavskii
On the basis of economic-mathematical models (EMM) a comparative assessment of the influence of the main natural factors on the design, technological, exergy and economic parameters and performance of geothermal heating systems (GHS) was carried out. It allowed creating and recommending a new express methodology of their calculation on the territory of Russia. The created methods of EMM and express analysis can provide the first stages of GHS design and, in particular, justification of investments and development of business plans. Examples are given for promising regions of Russia.
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Date submitted2003-06-16
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Date accepted2003-07-20
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Date published2004-09-09
Parameter development of polymeric steel tie bolt of the field workings at the mine SUBR
- Authors:
- E. I. Mikulin
- R. G. Minzaripov
The manufacturing application experience at SUBR mines of a steel-polymeric roof bolts is given. New parameters of roof bolts, for SUBR excavations, based on theoretical and practical researches are obtained. The results of experimental-industrial tests of lateral excavation supported by new designed steel-polymeric roof bolts are shown. The economical estimation of the steel-polymeric support is given.
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Date submitted2003-06-07
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Date accepted2003-07-09
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Date published2004-09-09
Rock structure and scale effect
- Authors:
- A. N. Stavrogin
Under conditions of uniaxial compression at strain rate variation from 10 +2 to 10 -8 s -1, samples of natural rock salt were investigated for strength. For the first time, a 40% drop in strength in the range of high speeds and a decrease in the work of fracture by tens of times were found, which contradicts the kinetic concepts. Experiments carried out on salt samples artificially produced by pressing at a pressure of 700 MPa showed good agreement with kinetic representations. The difference in the properties of natural salt and artificially prepared samples is explained by the difference in their structure: natural salt is characterized by a large scattering of structural crystallite sizes.
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Date submitted2003-06-03
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Date accepted2003-07-17
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Date published2004-09-09
Longitudinal studies of the stress-strain state of load-bearing structures in St. Petersburg Metro stations during operation
- Authors:
- N. I. Kulagin
- K. P. Bezrodnyi
- M. O. Lebedev
The results of long-term studies of the stress-strain state (SSS) of structural elements of St. Petersburg subway stations are presented. The obtained data indicate the continued growth of stresses on the linings during operation. At steady mountain pressure at the end of the observations, the redistribution of the stress state in the cross section of the stations continues.
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Date submitted2003-06-25
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Date accepted2003-07-27
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Date published2004-09-09
Problems of calculation of mine workings and underground structures lining
- Authors:
- N. S. Bulychev
The problems of calculation of mine workings' supports and underground structures' coverings, connected with application of the currently recognized provisions of the theory (mechanics) of underground structures to concrete objects of underground construction, are considered. According to the principle of interaction of shielding (lining) with an array of rocks, the stress state of underground structures depends on the characteristics of the initial field of stresses in the array, as well as the deformation characteristics of the rock material of structures. A special and significant role is played by the influence of underground construction technology to control the stress state of support structures. The correctness and reliability of the calculation also depends on the calculation methods used.
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Date submitted2003-06-24
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Date accepted2003-07-22
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Date published2004-09-09
Forecasting technique of tunnel exploitation stability of St. Petersburg underground
- Authors:
- A. G. Protosenya
- E. G. Kozin
In-situ measurements of tunnels deformation for Saint-Petersburg subway are given. Time dependable wave character of tunnels deformation in the form of rising and lowering was discovered. It was established that periodical rising and lowering of tunnels occur along the track section with disrupted rock mass and tectonic fissure. It was suggested that tunnel stability prediction technique is based on rate of it displacement.
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Date submitted2003-06-17
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Date accepted2003-07-29
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Date published2004-09-09
Calculation of tunnel linings of variable thickness taking into account the influence of the earth surface
A new analytical method for calculation of tunnel linings with thickness varying along the perimeter of cross-section, for the action of own weight of soil, pressure of ground water and liquid filling the tunnel, taking into account the influence of the earth surface, as well as the weight of buildings and structures on the surface, is proposed. The method is based on the consideration of interaction between the underground structure and the surrounding ground massif as elements of a single deformable system. Examples of calculations illustrating this method are given.
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Date submitted2003-06-13
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Date accepted2003-07-19
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Date published2004-09-09
Specific features of the formation of the vertical load on the column lining of the "Komendantsky Prospekt" subway station
- Authors:
- P. A. Demenkov
The paper shows the nature of formation of the vertical load on the column-type lining of the "Komendantsky Prospekt" station of the St. Petersburg subway deep-laid with regard to the technology of its construction. On the basis of numerous field studies, mathematical modeling by the finite element method (FEM) was carried out. The three-dimensional elastic and viscoelastic models at various stages of the station construction were used for the calculations. The calculations resulted in the construction of epures of vertical load distribution on the deep-filled metro station column lining. The character and regularities of its formation without and taking into account the influence of the middle tunnel face were revealed.