Geo-Technical mechanics
Latest Publications


TOTAL DOCUMENTS

239
(FIVE YEARS 103)

H-INDEX

2
(FIVE YEARS 1)

Published By National Academy Of Sciences Of Ukraine (Co. LTD Ukrinformnauka)

1607-4556, 2309-6004

2020 ◽  
pp. 3-21
Author(s):  
A.F. Bulat ◽  
◽  
T.V. Bunko ◽  
I.Ye. Kokoulin ◽  
V.V. Myroshnychenko ◽  
...  

In the article, the issues of terminology of technique philosophy related to the notions of a concept, a risk and an uncertainty are considered. It is noted that a concept in terms of philosophy is considered as a category of human thinking, of how a man being a subject perceives the environment: objects, processes, actions of other people. From philosophical point of view, a concept is characterized by four levels; "consciousness - authorial concept - concept of interpreter - collective consciousness". Definition of the levels can differ, but their sense remains unchanging. A concept is considerably wider than a notion and is syncretic by its content. Basic criterion, by which it is possible to distinguish between "a concept" and "a notion", is simple enough: if we can give a clear (of course, subjective) definition, then it is a notion, if we cannot – it is a concept. A concept becomes a notion when a subject has set it forth (authorial concept), listeners (readers) have interpreted it (interpreter concept), discussed and created a collective concept – after this the concept is formalized as notions. Good example of such chain of a concept transforming into totality of publicly-meaningful, clear and suitable for the practical use results is defending of a scientific dissertation. A risk is considered in philosophical understanding: it is impossible to formulate any universal definition for it as a risk is always subjective and inherent to a concrete participant of some technological or public process in concrete field. A risk should not be mixed up with an uncertainty, as a risk is a method for overcoming an uncertainty. A risk is a function of an uncertainty which does not have clear definition and can be estimated only partially. A risk relates to a subjective uncertainty only: an objective uncertainty should be only taken into account and cannot be an object of control as it cannot be diminished by way of experiments or analysis of statistics. A risk in philosophical understanding can be only a basis for further concretization by engineering sciences: there and only there it is possible to try (and it has been already partially realized) to work out methods for assessing a risk and use the obtained results for improving reliability of production and minimizing the accident rate.


2020 ◽  
pp. 32-46
Author(s):  
A.I. Voloshin ◽  
◽  
A.A. Rubel ◽  
B.I. Boyko ◽  
V.A. Rubel ◽  
...  

In order to ensure the cage directed motion, vertical shafts are reinforced with the shaft equipment of various designs: rigid, flexible, with no buntons, rope-profile. In this research, different existing design schemes of the shaft equipment, their advantages and disadvantages, design solutions with the rope-profile guides and discrete step of the shaft equipment installation between the tiers in the point of the cages meeting are considered and studied. Designing, research and installation of discrete reinforcing equipment with the rope-profile guides in the shafts in the point of the cages meeting can significantly diminish disadvantages of the existing (rigid and flexible) reinforcing equipment and can facilitate: to reduce the number of tiers arranged along the full depth of the shaft; to prolong trouble-free life; to cut capital construction costs due to less diameter of the shaft (for flexible shaft equipment); to make maintenance and repair essentially simpler; to reduce significantly metal content of the shaft equipment as compared to rigid shaft equipment; to reduce dynamic vibrations of the “cage-shaft equipment” system; to improve damping properties of the shaft equipment; to reduce the shaft aerodynamic resistance to the level of flexible shaft equipment; to improve reliability and safety of the shaft equipment operation; to eliminate the need to use balance ropes; to prolong life of the rope-profile guides to the level of rigid guides. The research and development of these structures and schemes are resulted in: improved reliability and durability of vertical shaft equipment and increased profitability of minerals extraction from deeper horizons. Introduction of the schemes with discrete step of reinforcing equipment installation in the point of cages meeting (in the middle of the shaft) for different locations of the tiers will significantly improve safety of vertical shaft equipment operation and the hoisting complex as a whole.


2020 ◽  
pp. 107-115
Author(s):  
Yu.Yu. Pidhoretskyi ◽  

In the article, the author presents results of mathematical modeling of operation of the venting relief structures made of honeycomb polycarbonate sheets and fixed in the standard window profiles, under the effect of explosion. In order to reproduce the explosion effect on venting relief structures, an approach to modeling dynamic systems was applied, which used a finite element method to approximate the basic general equations of dynamics added by the equations of the stress-strain state of a solid body. The applied approach differs by reproduction of the explosion process impact on the venting relief structures of this type by using equations which describe the motion of the dynamic system with accounting a contact interaction with the friction of honeycomb polycarbonate sheets and corresponding surfaces of the standard window profile locks. The honeycomb structure of the polycarbonate sheet was modeled by appropriate finite elements with considering the polycarbonate elastic properties. In order to implement numerical algorithms of this approach, a program code of the LS-DYNA computer system was used. The conducted numerical experiment on reproducing the explosion effect on the relief elements of this type of the venting relief structures made it possible to trace all stages of the honeycomb polycarbonate sheets deforming and moving under the action of explosion up to the exit of their edges from the window profile locks with the study of the corresponding stress-strain state parameters. By using this approach, reliably disclosure of the venting relief structures based on honeycomb polycarbonate sheets was investigated, and conditions for their reliable disclosure were identified with considering geometrical parameters of such type of venting relief structures opening and thickness of the honeycomb polycarbonate sheets. Results of the research have shown that reliable disclosure of the honeycomb polycarbonate sheets occurs within the range of the explosion overpressure, hence, confirming the effectiveness of such type of the venting relief structures used for protecting buildings against the explosion action.


2020 ◽  
pp. 127-137
Author(s):  
V.V. Nizhnyk ◽  
◽  
O.F. Nikulin ◽  
S.V. Pozdeev ◽  
D.O. Dobriak ◽  
...  

This article presents the current state of affairs in cases of explosions in Ukraine and preventive measures to protect against them. The relevance of studies on the substantiation of the methodology for calculating the parameters of easily disposable structures for explosive and fire hazardous premises has been determined. The analysis of domestic and foreign regulatory documents for the design and installation of window openings in buildings for various purposes is carried out. The permissible values of the overpressure of the explosion, which does not cause significant damage to building structures and is safe for people, are considered. The subject of the study is the effect of the amount of gas on the design parameters of the research stand for the experimental evaluation of easily disposable structures. The purpose of this work is to substantiate the design and the main technical parameters of the research stand for assessing the performance of easily sisposable structures. The essence of the proposed research method is to create an excess pressure from the explosion of a mixture of propane-butane with air in the working volume and to study the effect of this excess pressure of the explosion on a prototype of an easily disposable structure. An experimental stand for studying the processes of the influence of the magnitude of the overpressure of an explosion in a confined space on the design parameters of easily disposable structures is simple in design, provides an imitation of a part of a building (structure) fragment and makes it possible to study the possibility of using certain building materials with different geometric parameters as easily disposable structures, which, in turn, allows the researcher to obtain more reliable data for analysis. The existing experimental methods for evaluating the parameters of easily disposable structures are analyzed. The dimensions of the research stand and the parameters of its enclosing structures, the critical values of the overpressure of the explosion, which the stand should create, and the minimum amount of gas, the combustion of which will provide the necessary overpressure of the explosion in the stand, are substantiated. A fundamentally new stand for the experimental evaluation of the parameters of easily disposable structures, a program and experimental research methodology have been developed.


2020 ◽  
pp. 263-274
Author(s):  
O. Lozhnikov ◽  
◽  
R. Dychkovskyi ◽  

Purpose is an establishment of efficient parameters of a multi-section man-made deposit at the pulp clays storage on the surface of internal pit dumps during the development of placer deposits. The analytical research method was used to establish the main parameters of man-made deposits sections depending on their width and depth. A graphical research method was used to establish the downtime duration between formation of the first and second sections of the man-made deposit. It is established that division of the man-made deposit into five sections parallel to the mining front reduces time period till start of its operation from 8 to 5 years for it thickness 10 m and from 7 to 5 years at thickness 20 m. However, a significant disadvantage is the increassd number of sections in the man-made deposit from 2 to 5 is an increase in the volume of construction work from 0.27 to 1.11 million m3 at thickness 10 m, and from 0.53 to 2.15 million m3 at thickness 20 m, which confirms the necessity to find an effective number of sections in the man-made deposit and their parameters. The dependence between beginning of the works on filling the man-made deposit and the width of its first section delays start of the filling works, but too small width causes downtime at transiting from the first section to the second one. Efficient width of the man-made deposit first section is established, in which downtime is reduced from 7 years to 5.8 years, and volume of raw materials located outside the pit is reduced by 0.1 - 0.5 million m3 depending on the width of the first section. A method is proposed for determining an effective width of the first section in a two-section man-caused deposit, in which occurs while filling the sections. It is established that effective width of the first section oin the two-section man-made deposit with thickness of 10 m and with parameters of a typical pit development at mining of titanium-zirconium deposit is 241 m.


2020 ◽  
pp. 106-115
Author(s):  
O.P. Krukovskyi ◽  
◽  
S.A. Kurnosov ◽  
Yu.Yu. Bulich ◽  
Yu.S. Opryshko ◽  
...  

2020 ◽  
pp. 74-81
Author(s):  
K.А. Bezruchko ◽  
◽  
L.I. Pymonenko ◽  
V.I. Baranovskyi ◽  
V.V. Hopkalo ◽  
...  
Keyword(s):  

2020 ◽  
pp. 3-14
Author(s):  
A.F. Bulat ◽  
◽  
T.V. Bunko ◽  
I.A. Yashchenko ◽  
I.Ye. Kokoulin ◽  
...  
Keyword(s):  

Sign in / Sign up

Export Citation Format

Share Document