scholarly journals METHOD OF ESTIMATION OF RHEOLOGICAL CHARACTERISTICS OF ROCK MASS USING DATA OF UNDERGROUND GEODESY IN TERMS OF VISCOELASTIC MODEL

2019 ◽  
Vol 2 (4) ◽  
pp. 229-236
Author(s):  
Anton Panov ◽  
Leonid Nazarov ◽  
Nelli Miroshnichenko
Keyword(s):  
Numerical Experiments ◽  
Viscoelastic Model ◽  
Measurement Data ◽  
Mineral Deposits ◽  
Room And Pillar Mining ◽  
Pillar Mining ◽  
Using Data ◽  
Determination Of Parameters

Method of estimation of rheological properties of constructive elements of room-and-pillar mining of solid mineral deposits is considered. The method is based on solution of inverse problems of mixed type in the context of two dimensional viscoelastic model of structure. Feasibility of in situ determination of parameters for constitutive equations describing rheological deformation of rocks is shown. The numerical experiments implemented with synthetic input data (relative displacements recorded at the points of mined-out void boundary using in-mine geodetics techniques) for the preset absolute precision of equipment provide the measurement data amount required to ensure resolvability of inverse problem.

scholarly journals DETERMINATION OF DEFORMATION PROPERTIES AND NATURAL STRESSES IN ROCK MASS BY UNDERGROUND GEODESY DATA

2021 ◽  
Vol 2 (4) ◽  
pp. 52-61
Author(s):  
Anton V. Panov ◽  
Leonid A. Nazarov
Keyword(s):  
Inverse Problem ◽  
Measurement Data ◽  
Domain Size ◽  
Structural Elements ◽  
Room And Pillar Mining ◽  
3D Geomechanical Model ◽  
Deformation Properties ◽  
Pillar Mining ◽  
Typical Configuration

The authors have developed and implemented a 3D geomechanical model using the finite element method for a typical configuration of an underground space during room-and-pillar mining. The authors formulate and solve an inverse problem on determination of values and orientation of external horizontal stresses and deformation characteristics of structural elements of the geotechnology by the measurement data of sidewall convergence in rooms in the course of mining. The level curves of different objective functions are analyzed, the mixed inverse problem resolvability is demonstrated, and the equivalence domain size is correlated with the relative error of input data.

Deformation Characteristics of a Technological Pillar in the Chamber-Pillar Mining System/Charakterystyka Deformacyjna Filara Technologicznego W Komorowo-Filarowym Systemie Eksploatacji

2014 ◽  
Vol 59 (2) ◽  
pp. 323-335
Author(s):  
Wiesław Grzebyk ◽  
Lech Stolecki
Keyword(s):  
Underground Mining ◽  
Measurement Techniques ◽  
Measurement Data ◽  
Deformation Characteristics ◽  
Mining System ◽  
The Face ◽  
Pillar Mining ◽  
In Situ Observations ◽  
Mining Works

Abstract The article presents the suitability of the new measurement techniques for monitoring deformations of the technological pillars and fragments of the face in underground mining. The conducted observations concerned the mined pillar located in the lead of mining field G-3/4 of Rudna mine (mine belongs to KGHM Polska Miedź S.A.) in a situation of constant progress of mining works in its direction. The observations conducted underground provided results demonstrating the suitability of the applied observation techniques in this area. The obtained measurement data directly describe the volumetric changes which form the basis for assessing the stress of the rock formation. This issue is well recognised based on the tests on rock samples. Further studies should concern the transfer of these experiences to the results of in situ observations.

Modeling FEBEX Large-Scale In Situ Test

1997 ◽  
Vol 506 ◽  
Author(s):  
A. Gens ◽  
E.E. Alonso ◽  
A. Garcia-Molina ◽  
F. Huertas ◽  
J.L. Santiago
Keyword(s):  
Large Scale ◽  
Longitudinal Section ◽  
Sensitivity Analyses ◽  
Critical Parameters ◽  
In Situ Test ◽  
Determination Of Parameters ◽  
Available Information ◽  
Real Test

ABSTRACTThis paper reports the coupled thermo-hydro-mechanical (THM) analyses of the “in situ” test carried out during the pre-operational stage of the FEBEX project. The determination of parameters has been performed using the results of the characterization stage and other available information. The results of the analyses provide a good understanding of expected test behaviour. This understanding is enhanced by the performance of a quite extensive programme of 1-D sensitivity analyses in which the values of critical parameters are varied. Two dimensional effects are discussed on the basis of the results of 2-D axisymmetric THM analyses carried out using a longitudinal section that provides a better representation of real test geometry.

In Situ Determination of Parameters of Hydrogen Isotopes Interaction with Materials Using Dynamic Sorption Method

2020 ◽  
Vol 76 (3) ◽  
pp. 333-340 ◽  
Author(s):  
T. V. Kulsartov ◽  
Zh. A. Zaurbekova ◽  
I. E. Kenzhina ◽  
M. T. Gabdullin ◽  
Yu. V. Ponkratov ◽  
...  
Keyword(s):  
Hydrogen Isotopes ◽  
Dynamic Sorption ◽  
Sorption Method ◽  
Determination Of Parameters

scholarly journals LONG-TERM STABILITY MONITORING OF THE MINING BLOCKS IN ESTONIAN OIL SHALE MINES

2006 ◽  
Vol 1 ◽  
pp. 206
Author(s):  
J.-R. Pastarus
Keyword(s):  
Influence Factors ◽  
Monitoring Methods ◽  
Mining System ◽  
Term Stability ◽  
Long Term Stability ◽  
Room And Pillar Mining ◽  
Convergence Method ◽  
Pillar Mining

This paper deals with long-term stability prediction and monitoring methods by room-and-pillar mining system. Roof-to-floor convergence and conditional thickness methods suit for calculations. They allow determination of the location, area and time of the collapse in a mining block. The uncertainty in time is less than 10 % at the 95 % confidence level. Roof-to-floor convergence method is preferred; it takes into consideration all the geological and mining feature in the critical area. Conditional thickness method demands supplementary investigations, determination of the influence factors on the process. The applicability of these methods is clearly demonstrated.

scholarly journals Determination of the stability of residual pillars in a room-and-pillar mining goaf under eccentric load

2021 ◽  
Vol 7 ◽  
pp. 9122-9132
Author(s):  
Nan Zhou ◽  
Erbao Du ◽  
Meng Li ◽  
Jixiong Zhang ◽  
Chaowei Dong
Keyword(s):  
Eccentric Load ◽  
Room And Pillar Mining ◽  
Pillar Mining ◽  
The Stability

Determination of parameters of short circuit of power transformer by means of mathematical modeling

2017 ◽  
Vol 26 (102) ◽  
pp. 110-119
Author(s):  
D. S. Yarymbash, ◽  
◽  
S. T. Yarymbash, ◽  
T. E. Divchuk, ◽  
D. A. Litvinov
Keyword(s):  
Mathematical Modeling ◽  
Power Transformer ◽  
Short Circuit ◽  
Determination Of Parameters

INDIREKTE PAPIERCHROMATOGRAPHISCHE METHODE ZUR BESTIMMUNG DER HARNOESTROGENE

1961 ◽  
Vol 38 (4) ◽  
pp. 545-562 ◽  
Author(s):  
L. Kecskés ◽  
F. Mutschler ◽  
I. Glós ◽  
E. Thán ◽  
I. Farkas ◽  
...  
Keyword(s):  
Pregnant Women ◽  
Granulosa Cell ◽  
Iron Content ◽  
List Type ◽  
Granulosa Cell Tumour ◽  
Hydrolysis Of ◽  
Phenol Fraction ◽  
Qualitative Determination

ABSTRACT 1. An indirect paperchromatographic method is described for separating urinary oestrogens; this consists of the following steps: acidic hydrolysis, extraction with ether, dissociation of phenol-fractions with partition between the solvents. Previous purification of phenol fraction with the aid of paperchromatography. The elution of oestrogen containing fractions is followed by acetylation. Oestrogen acetate is isolated by re-chromatography. The chromatogram was developed after hydrolysis of the oestrogens 'in situ' on the paper. The quantity of oestrogens was determined indirectly, by means of an iron-reaction, after the elution of the iron content of the oestrogen spot, which was developed by the Jellinek-reaction. 2. The method described above is satisfactory for determining urinary oestrogen, 17β-oestradiol and oestriol, but could include 16-epioestriol and other oestrogenic metabolites. 3. The sensitivity of the method is 1.3–1.6 μg/24 hours. 4. The quantitative and qualitative determination of urinary oestrogens with the above mentioned method was performed in 50 pregnant and 9 non pregnant women, and also in 2 patients with granulosa cell tumour.

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