scholarly journals STRESS-STRAIN BEHAVIOR OF ROCK MASS AROUND CYLINDRICAL EXCAVATIONS WITH THE PRESET CAUCHY STRESS STRESSES AND DISPLACEMENTS AT THE BOUNDARIES

2021 ◽  
Vol 2 (4) ◽  
pp. 158-163
Author(s):  
Anvar I. Chanyshev ◽  
Igizar M. Abdulin
Keyword(s):  
Rock Mass ◽  
Symmetry Axis ◽  
Strain Analysis ◽  
Polar Angle ◽  
Surrounding Rock ◽  
Rotation Vector ◽  
Cauchy Stress ◽  
Stress Strain ◽  
Strain Behavior

The authors solve the problem on the stresses and strains of rock mass around a cylindrical excavation with the preset vectors of the Cauchy stresses and displacements at the boundary. It is assumed that the surrounding rock mass is elastic. Along the cylindrical excavation (free of stresses), displacements are measured as functions of two surface coordinates (polar angle and length along the symmetry axis of the excavation). These measurements are used to determine all components of tensors of stresses and strains at the boundary, and all coordinates of rotation vector. It is shown how this information can be used in the stress-strain analysis of rock mass farther from the excavation.

3D finite element-based modeling of discontinuities

2020 ◽  
pp. 35-39
Author(s):  
I. E. Semenova ◽  
◽  
S. V. Dmitriev ◽  
A. A. Shestov ◽  
◽  
...  
Keyword(s):  
Finite Element ◽  
Rock Mass ◽  
Strain Analysis ◽  
Interface Element ◽  
The Finite Element Method ◽  
Stress Strain ◽  
Interface Elements ◽  
Strain Behavior ◽  
Improve Reliability ◽  
Optimal Type

A rock mass is composed of blocks, and the interfaces of various scale blocks represent different kind discontinuities. Such structure is also associated with nonuniformity of stresses. The stress–strain behavior of rock mass in the Khibiny apatite–nepheline massif in the course of mining is governed by natural geological and induced faulting. This study considers modification of the finite element method in the stress–strain analysis of rocks with regard to deformation at interfaces of different-modulus media. After 2D tests of interface elements, an optimal type of the interface element was selected for the 3D modification implementation. The latter can improve reliability of geomechanical forecasts in mineral mining in complicated geological and geodynamic conditions. From the test data on modification of interface elements, the optimal interface element is assumed to be the six-node interface element proposed by V. Kalyakin and Jianchao Li. The six-node interface element is introduced in the model of a tunnel with simulation of an unloading line at the boundary. The adequate results on adjacent rock deformation are obtained. The 3D interface element modification reveals its peculiarities and limitations as regards introduction in finite element models of mineral deposits and enclosing rock mass. The ways of solving these problems are proposed.

Influence exerted by underground excavation shape and by effective stresses on the formation of a tensile strain zone at a depth greater than 1 km

2020 ◽  
pp. 67-75
Author(s):  
Van Min Nguyen ◽  
V. A. Eremenko ◽  
M. A. Sukhorukova ◽  
S. S. Shermatova
Keyword(s):  
Rock Mass ◽  
Cross Sections ◽  
Tensile Strain ◽  
Rock Fracture ◽  
Strain Analysis ◽  
Surrounding Rock ◽  
Underground Excavation ◽  
Secondary Stress ◽  
Principal Stresses ◽  
Mining Depth

The article presents the studies into the secondary stress field formed in surrounding rock mass around underground excavations of different cross-sections and the variants of principal stresses at a mining depth greater than 1 km. The stress-strain analysis of surrounding rock mass around development headings was performed in Map3D environment. The obtained results of the quantitative analysis are currently used in adjustment of the model over the whole period of heading and support of operating mine openings. The estimates of the assumed parameters of excavations, as well as the calculations of micro-strains in surrounding rock mass by three scenarios are given. During heading in the test area in granite, dense fracturing and formation of tensile strain zone proceeds from the boundary of e ≥ 350me and is used to determine rough distances from the roof ( H roof) and sidewalls ( H side) of an underground excavation to the 3 boundary e = 350me (probable rock fracture zone). The modeling has determined the structure of secondary stress and strain fields in the conditions of heading operations at great depths.

Environmental aspects of mining geomechanics

2021 ◽  
pp. 4-7
Author(s):  
Yu. P. Galchenko ◽  
Keyword(s):  
Strain Analysis ◽  
Human Beings ◽  
Environmental Aspects ◽  
Russian Science ◽  
Stress Strain ◽  
Strain Behavior ◽  
Mineral Sector ◽  
Living Space ◽  
Nature And Society ◽  
Induced Changes

The modern technocratic civilization has grown in the conditions of perpetual and irresolvable antagonistic contradiction between the biological essence of human beings as elements of the natural biota of the Earth and the abiological methods used to obtain the needed energy through extermination of the natural biota and its replacement by the anthropogenic biota of different functional purposes. The material and energy basis of the technosphere as an artificial living space for a human being is the substance produced as a result of irreversible destruction of the lithosphere. Permanently increasing difficulty and deeper level of mining make mining geomechanics the top-priority area of research. The stress–strain analysis is a requisite component of studies aimed at selecting a geotechnology and determining its parameters. This analysis evaluates mining-induced stresses. The values of such stresses are determined mainly at critical points of boundaries of mining-caused voids with a view to ensuring stability of exposed surfaces and pillars. The feasibility of ecological evaluation of mining-induced changes in the stress–strain behavior of the disturbed lithosphere using the appropriate procedure being developed can make it possible to rank geotechnologies using the related criteria. This allows taking one more step towards an engineering framework for the concept of sustainable nature and society activity in the course of the mineral sector development. This study has been supported by the Russian Science Foundation, Project No. 19–17–00034).

Change in stress-strain behavior of coal-rock mass during coal mining

2020 ◽  
pp. 5-24
Author(s):  
V.N. Zakharov ◽  
A.V. Shlyapin ◽  
V.A. Trofimov ◽  
Yu.A. Filippov
Keyword(s):  
Rock Mass ◽  
Coal Mining ◽  
Stress Strain ◽  
Strain Behavior ◽  
Coal Rock

Of forming loads on the mounting of shaft shafts in the hierarchic block environment under the influence of modern geodynamic movements

2020 ◽  
pp. 161-169
Author(s):  
I. L. Ozornin ◽  
A. E. Balek ◽  
A. N. Kaiumova
Keyword(s):  
Rock Mass ◽  
High Stress ◽  
Surrounding Rock ◽  
Strain Behavior ◽  
Underground Openings ◽  
Hierarchical Block Structure ◽  
The Subject ◽  
Nonuniform Stress Field ◽  
Strength Rock

The subject of the research is the lining of mine shafts and surrounding rock mass. The subject matter is the features of the stress-strain behavior of lining and adjacent rock mass in shafts and near-shaft underground openings in the Tenth Anniversary of Independence of Kazakhstan mine located in the tectonically high-stress and low-strength rock mass. The loading of the lining in the shafts and near-shaft openings in the Tenth Anniversary of Independence of Kazakhstan mine during construction is investigated, and the damages of the lining in the course of drivage in the nonuniform stress field are analyzed. The long-term periodic in-situ instrumental monitoring of stress variation in the lining of the mine shafts and near-shaft openings revealed the main influences on the process of load formation on the lining in the conditions of post-limiting deformation of surrounding rock mass. It is validated that the surrounding rock mass of the mine has a complex hierarchical block structure and is subjected to modern geodynamic movements. As the depth of mining is increased, surrounding rock mass of the mine shafts transfers to the condition of postlimiting stresses and strains. As a consequence, the lining of the shafts and near-shaft openings at different stages of construction experiences nonuniform concentrated loads, which violates integrity of the lining.

CALCULATION OF THE GEOMECHANICAL STATE OF MINE WORKING SUPPORT AND SURROUNDING ROCK MASS IN CONDITIONS OF MINING ORE DEPOSITS IN EAST KAZAKHSTAN

2020 ◽  
Vol 2 ◽  
pp. 89-97
Author(s):  
Andrey A. Krasnovsky ◽  
Viktor M. Seryakov ◽  
Yuri N. Shaposhnik ◽  
Denisi A. Shokarev
Keyword(s):  
Rock Mass ◽  
Mine Working ◽  
Strain State ◽  
Ore Deposits ◽  
Surrounding Rock ◽  
Stress Fields ◽  
Uniform Pressure ◽  
Stress Strain ◽  
East Kazakhstan ◽  
Geomechanical State

The statement of the problem of determining the stress-strain state of support and rock mass around the mine working in unstable rocks, in case of voids filling with phenol resins is proposed. The initial parameters used in the calculations correspond to the conditions of mining ore deposits in East Kazakhstan. The distribution character of stress fields in the support and their change depending on geometric sizes of the area filled with phenol resins is determined. It is shown that using phenol resins causes formation of a uniform pressure of surrounding rocks on the arch part of the support and facilitates an increase in its stability.

Stress–strain analysis in coal and rock mass under traditional mining with full caving and in technology with backfilling

2018 ◽  
pp. 15-17 ◽  
Author(s):  
K. S. Kolikov ◽  
◽  
I. E. Mazina ◽  
A. I. Manevich ◽  
◽  
...  
Keyword(s):  
Rock Mass ◽  
Strain Analysis ◽  
Stress Strain

Determining Stress-Strain Behavior of Zr60Cu10Al15Ni15 Bulk Metallic Glass Using Object Oriented Finite Element Analysis

2017 ◽  
Vol 29 ◽  
pp. 1-8 ◽  
Author(s):  
Ketul Arvindbhai Patel ◽  
Ganesh R. Karthikeyan ◽  
S. Vincent
Keyword(s):  
Mechanical Properties ◽  
Finite Element Analysis ◽  
Finite Element ◽  
Metallic Glass ◽  
Strain Analysis ◽  
Indentation Test ◽  
Object Oriented ◽  
Stress Strain ◽  
Element Analysis ◽  
Strain Behavior

Determining mechanical properties of Bulk Metallic Glasses (BMGs) requires synthesizing of the alloys in bulk form. However obtaining metallic glass in bulk form is quite challenging due to its tendency towards crystallization. In such circumstances it is beneficial to determine the mechanical properties of materials using finite elemental analysis of microstructures. Thus, in the present investigation, using Object Oriented Finite Element Analysis (OOF2) software package, Stress-Strain analysis has been carried out on Zr60Cu10Al15Ni15 BMG to determine such mechanical properties. Specimen of Zr60Cu10Al15Ni15 BMG exhibiting three microstructurally distinct regions amorphous, partial crystalline and crystalline regions was used for this analysis. The Stress-Strain relationship have been estimated for each of the three distinct phases and the results are validated by determining the Modulus of Elasticity for all the phases and comparing it with the available experimental results from Nano-indentation test.

Assessment of influence of short-period geodynamic movements on stress-strain behavior of rock mass

2020 ◽  
pp. 90-104
Author(s):  
Yu. P. Konovalova ◽  
V. I. Ruchkin
Keyword(s):  
Rock Mass ◽  
Strain Tensor ◽  
Space Distribution ◽  
Cycle Duration ◽  
Stress Strain ◽  
Strain Behavior ◽  
Principal Axes ◽  
Short Period ◽  
Check Points ◽  
Cyclic Movement

Geodynamic diagnostics of rock mass is critical in terms of safe arrangement and operation of subsoil use objects. The modern geodynamic movements are one of the factors that govern the stress-strain behavior of rocks. The experimental research accomplished in the recent decades show that geodynamic movements are the wide-spread phenomena of complex time-and-space distribution. It is conditionally assumed to distinguish between the trend movements of the same direction and velocity over the period of observations and the cyclic short-period movements with cycle duration from a few minutes to a few hours. The cyclic short-period geodynamic movements can exert direct or indirect impact on subsoil use objects. The cyclic nature is governed by many natural factors. The influence of one or another factor on the stress-strain behavior of rock mass is yet unstudied unambiguously to date. However, it is evident that strains governed by the cyclicity of movements should be taken into account in geodynamic diagnostics. The implemented studies of short-period movements on testing grounds by continuous monitoring using GNSS methods for many hours at spacing from two hundred meters to two kilometers revealed that directions of displacement of check points frequently exceeded accuracy of their determination. During the experiments, a procedure was developed to determine parameters of strain tensor in rock mass based on the prevailing direction and amplitude of short-period movements. The amplitude of short-period movement is a difference between the minimal and maximal values of displacements in a set of discrete measurements within continuous observation session. The obtained field of strains was compared with the values calculated by the data on the trend geodynamic movements for 6 years with the same check points in the same pattern. The correlation is found between the orientations of principal axes of strain tensors calculated by the data on the trend and shortperiod movements. The developed procedure makes it possible to take into account the shortperiod cyclicity of the modern geodynamic movements, and the found correlation between the orientation of strain tensor of the trend and cyclic movement enable express estimation of changes in the stress-strain behavior of rocks.

Sign in / Sign up

Export Citation Format

Share Document