Deformations of the Protection Shelf in the “Wapno” Salt Mine, Based on Model Studies

2014 ◽  
Vol 59 (4) ◽  
pp. 869-886
Author(s):  
Grzegorz Kortas ◽  
Agnieszka Maj
Keyword(s):  
Viscous Medium ◽  
Stress And Strain ◽  
Salt Mine ◽  
Flow Paths ◽  
Model Studies ◽  
Salt Mines ◽  
Multi Level ◽  
Pillar Structure ◽  
New Research ◽  
Distribution Of Stress

Abstract The catastrophic mine failure resulting from the inrush of water into the Wapno Salt Mine was probably caused by a fracture in the roof protection shelf. The purpose of the present study was to apply the method of the homogenization of the multi-level room-and-pillar structure in the Wapno Salt Mine for 3D+t modelling of the elastic-viscous medium to determine the distribution of stress and strain, and, on that basis, to estimate the geomechanical conditions existing in the roof shelf. This paper presents briefly the spatial development of the salt mine’s structure and the results of the surveying measurements carried out during the salt mine’s operation and after the mine was flooded. Those results constituted a basis for the verification of the introduced homogenization parameters, i.e. the time-dependent changes of the elasticity modulus and the susceptibility to creep at particular salt mine’s levels. A simulated process demonstrated the development of positive values of principle stresses, increasing with time, and of omnidirectional tensile strains. In such conditions, the cracking of the protection shelf body could proceed, also with opening of water flow paths from the dome cap into the salt mine’s workings. This paper presents a new research method, the results of its application, and the obtained distribution of stresses and strains that can be useful for the assessment of water hazard in other salt mines.

scholarly journals The therapeutic effect of a person staying in a salt mine due to the low background level of atomic radiation

2020 ◽  
Vol 17 (5) ◽  
pp. 279-283
Author(s):  
Gayaz H. Harisov ◽  
Aleksander G. Zavorotny
Keyword(s):  
Experimental Study ◽  
Therapeutic Effect ◽  
Salt Spray ◽  
Background Level ◽  
Salt Mine ◽  
Low Background ◽  
Salt Mines ◽  
Low Levels

The therapeutic effect of people staying in salt mines is currently explained by the fact that people inhale salt spray particulates. Based on an experimental study, the article proves that this therapeutic effect is the result of super-low levels of atomic radiation in the space of salt mines.

Wind Load Simulation Test for the Vehicle Mounted Extensible Mast System

2013 ◽  
Vol 805-806 ◽  
pp. 1794-1799
Author(s):  
Zhao Li ◽  
Chen Long Yang ◽  
Yun Xu ◽  
Yue Chao Chen
Keyword(s):  
Control Method ◽  
Wind Load ◽  
Test Method ◽  
Load Force ◽  
Stress And Strain ◽  
Thin Wall ◽  
Lateral Tension ◽  
Transformation Formulas ◽  
Distribution Of Stress ◽  
Load Simulation

Based on the Structure and wind load force characteristics of the vehicle mounted extensible mast system, a test method for the wind load simulation of the system was designed. According to the thin wall part structural feature, a method that adding lateral tension at the flanges of the mast was used to simulate wind load. Calculation method of the theoretical wind load force was given, and the transformation formulas between loading force needed and theoretical wind force was put forward, as well the control method of the test based on PID control algorithm was described. Simulation of the force condition under trapezoidal load was given by ANSYS. The results showed that using the load scheme designed, the distribution of stress and strain was almost the same as continuous load, as well as the value and position of the maximum stress and strain.

Distribution of stress and strain along the porcine aorta and coronary arterial tree

2004 ◽  
Vol 286 (6) ◽  
pp. H2361-H2368 ◽  
Author(s):  
Xiaomei Guo ◽  
Ghassan S. Kassab
Keyword(s):  
Cardiovascular System ◽  
Vascular System ◽  
Circumferential Stress ◽  
Stretch Ratio ◽  
Opening Angle ◽  
Stress And Strain ◽  
Cauchy Stress ◽  
Arterial Tree ◽  
Vascular Growth ◽  
Distribution Of Stress

The existence of a homeostatic state of stresses and strains has been axiomatic in the cardiovascular system. The objective of this study was to determine the distribution of circumferential stress and strain along the aorta and throughout the coronary arterial tree to test this hypothesis. Silicone elastomer was perfused through the porcine aorta and coronary arterial tree to cast the arteries at physiological pressure. The loaded and zero-stress dimensions of the vessels were measured. The aorta (1.8 cm) and its secondary branches were considered down to 1.5 mm diameter. The left anterior descending artery (4.5 mm) and its branches down to 10 μm were also measured. The Cauchy mean circumferential stress and midwall stretch ratio were calculated. Our results show that the stretch ratio and Cauchy stress were lower in the thoracic than in the abdominal aorta and its secondary branches. The opening angle (θ) and midwall stretch ratio (λ) showed a linear variation with order number ( n) as follows: θ = 10.2 n + 63.4 ( R2 = 0.989) and λ = 4.47 × 10−2 n + 1.1 ( R2 = 0.995). Finally, the stretch ratio and stress varied between 1.2 and 1.6 and between 10 and 150 kPa, respectively, along the aorta and left anterior descending arterial tree. The relative uniformity of strain (50% variation) from the proximal aorta to a 10-μm arteriole implies that the vascular system closely regulates the degree of deformation. This suggests a homeostasis of strain in the cardiovascular system, which has important implications for mechanotransduction and for vascular growth and remodeling.

Detection of mantle CO2 in an underground salt mine via long-term and high-resolution monitoring by laser-based isotope techniques

2020 ◽  
Author(s):  
Alexander H. Frank ◽  
Robert van Geldern ◽  
Anssi Myrttinen ◽  
Axel Zimmer ◽  
Martin Zimmer ◽  
...  
Keyword(s):  
Ambient Air ◽  
High Temporal Resolution ◽  
Anthropogenic Influences ◽  
Salt Mine ◽  
Central Germany ◽  
Salt Mines ◽  
Set Up ◽  
The One ◽  
Isotope System

<p>Salt deposits may be affected by post-depositional CO<sub>2</sub> intrusions. In central Germany, such CO<sub>2</sub> contributions from the mantle may originate from Tertiary Rhön- and Vogelsberg-volcanism. The intrusion of those gases may cause technical and operational implications for storage caverns and salt mines.</p><p>Carbon isotope compositions of CO<sub>2</sub> are useful tools to differentiate between sources and are expressed as δ<sup>13</sup>C values in ‰ versus an international standard known as the Vienna Pee Dee Belemnite (VPDB). Typical average endmember values for CO<sub>2</sub> from the mantle are -5.1 ‰, while background air and anthropogenic influences range around averages of -11.9 ‰ and -29.8‰. Detection of fluctuations between these endmembers can be challenging with discrete sampling. This can be overcome by high-temporal resolution and long-term monitoring.</p><p>Towards this purpose, a laser-based isotope system was set up in an active underground salt mine in central Germany. For 34 days, continuous measurements of δ<sup>13</sup>C and concentrations of CO<sub>2</sub> were generated close to a site where mantle CO<sub>2</sub> intrusions were suspected. A timer regularly switched intakes from two capillaries, of which one was placed inside a borehole and the other in ambient air of the mine. Measured CO<sub>2</sub> concentrations ranged between 700 and 1600 ppmV, while δ<sup>13</sup>C values ranged between -21.5 ‰ and -11.5 ‰. Lower concentrations coincided with more positive isotope values and occurred around weekends when anthropogenic influences in the mine were less.</p><p>While influences of fresh air venting may have caused these weekly shifts, the admixture of mantle CO<sub>2</sub> seemed to play a continuous role. This is because small differences between the capillary from the borehole and the one with ambient air existed throughout the time series. Our results indicate that short-term dynamics on the order of hours to days are overlain by admixtures mantle gas intrusions of CO<sub>2</sub>.</p>

scholarly journals Ambidexterity as a New Research Paradigm: Examining the Mediating Role of Employees Goal Orientation, Exploitation and Exploration

2020 ◽  
Vol V (II) ◽  
pp. 94-105
Author(s):  
Gul Bahar ◽  
Shazia Akhtar
Keyword(s):  
Goal Orientation ◽  
Cognitive Factors ◽  
Organizational Ambidexterity ◽  
Mediating Role ◽  
Software Companies ◽  
Level Data ◽  
Multi Level ◽  
New Research ◽  
The Impact

The aim of this study was to empirically validate the impact of ability-enhancing HR bundles on organizational ambidexterity through mediation of employees cognitive factors and employees exploration and exploitation. The multi-level data was collected from 600 employees of the software companies and analyzed through MEDTHREE analysis and SEM using AMOS software. Data was collected in two-time waves and results revealed positive relationship between ability-enhancing HR bundles and organizational ambidexterity. This study contributes to literature by providing new insights and by investigating links of ability-enhancing HR bundles with organizational ambidexterity directly and indirectly.

Numerical Simulation of the Piercing Process of Large-Sized Seamless Steel Tube

2013 ◽  
Vol 319 ◽  
pp. 444-450 ◽  
Author(s):  
Feng Liu ◽  
Yun Long Qiu ◽  
Zhang Hua Song ◽  
Shuai Wei Wang
Keyword(s):  
Strain State ◽  
Tube Wall ◽  
Steel Tube ◽  
Necessary Condition ◽  
Stress And Strain ◽  
Complex State ◽  
Seamless Steel Tube ◽  
Distribution Of Stress ◽  
Crack Defect ◽  
Seamless Steel

In the piercing process of the large-sized seamless steel tube, the rollers and plug affected on the billet with extrusion and friction. It made that the stress and strain state of metal is very complicated. In the complex state, the casting shrinkage and void produced by molten steel solidification became the crack defect in the middle of tube wall. The simulation of the piercing process of large sized seamless steel tube was performed by FEM in this paper. The material is stainless steel TP321. The distribution of stress was analyzed. It was obtained that the circumferential shear stress is the necessary condition of produced the layered defects in the tube wall. The paper studied the state of strain in the tube. The distribution of all kinds of strain was gotten. That could provide the theory guide for the elimination of the crack defect in the large-sized seamless steel tube.

Finite Element Analysis of Globular Indexing Cam Mechanism Based on ANSYS

2012 ◽  
Vol 501 ◽  
pp. 335-338
Author(s):  
De Gong Chang ◽  
Song Mei Li ◽  
Cong Feng An
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Stress And Strain ◽  
Single Individual ◽  
Element Analysis ◽  
Cam Mechanism ◽  
Analysis Process ◽  
Resistance Moment ◽  
Indexing Mechanism ◽  
Distribution Of Stress

In this paper, the key components of globular indexing cam mechanism are analyzed by using the ANSYS finite element analysis software to solve the distribution of stress and strain of Globular indexing institutions caused by resistance moment. It is more intuitive and appropriate than the ever research of the single individual modal analysis process, and more easy to grasp the analysis results accuracy. It provides more solid theoretical basis for the production and application of globular indexing mechanism.

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