Fundamentals of geotechnics in the cryolithozone

2019 ◽  
Author(s):  
Лев Хрусталев ◽  
Lev Hrustalev
Keyword(s):  
Cost Optimization ◽  
Evaluation Methods ◽  
Scientific Basis ◽  
Site Preparation ◽  
Mechanical Interaction ◽  
Engineering Structures ◽  
The Stability ◽  
Permafrost Regions

The means of controlling the stability of engineering structures in the permafrost regions, methods of modification for frozen, thawing and unfrozen soils and ways of site preparation are discussed. Evaluation methods of thermal and mechanical interaction between structures and soils of bases are presented. The scientific basis of optimizing engineering choices on the base of geotechnical systems reliability and cost optimization are given. Interaction of buildings and structures are analyzed.

Study and Practice on the Technology of Filling Mining in Xin Wen Mining Area

2011 ◽  
Vol 121-126 ◽  
pp. 2892-2896
Author(s):  
Ming Tao Gao ◽  
Ming Zhang ◽  
Ming Zhou
Keyword(s):  
Mining Area ◽  
Scientific Basis ◽  
Surface Subsidence ◽  
Open Pit ◽  
Coal Waste ◽  
Coordinated Development ◽  
Underground Disposal ◽  
Rock Movement ◽  
The Stability ◽  
Technology Processes

Because of mine production, the open-pit enission of coal gangue solid waste and surface subsidence are one of important causes to failure the mining area land and environment, so the key technology, processes and equipment of filling mining to replace coal have been developed, which convergences the existing system of mining technology, And the stability theory of the control of filling mining rock movement and the method of surface subsidence prediction have been established, which provides a scientific basis for equipment Selection and the design of subsidence control; the key technologies of filling mining to replace coal is successfully applicated, which significantly improves the recovery rate of coal resources in China and constructs the new coordinated development model that is combined by the underground disposal of coal waste, mining subsidence control and the “under three”safe coal mining, through the above, the target of green mining and the coordinated development of mining social, economic and environmental will be achieved.

IMPROVING THE MECHANISMS FOR CONTROLLING BRENT AND URALS OIL PRICE FORMATION AS A CONDITION FOR STRENGTHENING ECONOMIC SECURITY OF RUSSIA

2020 ◽  
Vol 10 (10) ◽  
pp. 2442-2449
Author(s):  
T.M. Mazurchuk ◽  
◽  
S.G. Arnett ◽  
Keyword(s):  
Oil And Gas ◽  
Scientific Basis ◽  
Economic Security ◽  
Price Formation ◽  
Economic Sectors ◽  
Fuel Prices ◽  
Russian Economy ◽  
Other World ◽  
The Stability ◽  
The Impact

The authors of the work investigate one of the key areas of the Russian economy - the oil industry. It is hydrocarbons that account, on average, up to 40% of the Russian budget revenues. Oil revenues provide macroeconomic stability of the state, employment of the population in the oil and gas sector and related industries, as well as the stability of the ruble currency in the international market and prices for most types of products in the domestic market. The aim of the work is to study the possibilities of improving the current mechanisms for controlling price formation for key brands of hydrocarbons in order to increase the economic and energy security of the Russian Federation. The scientific study also analyzes the impact of the prices for Urals and Brent crude oil on the Russian ruble quotes against the US dollar and other world currencies. The correlation between the increasing of main oil brands value on the hydrocarbon market and strengthening of the Russian currency, as well as the filling the Reserve and other national funds, as one of the factors in the development of the Russian economy, is studied. The scientific basis of the research was Russian and foreign publications, state statistical materials, opinions and assessments of experts in the field, as well as the authors’ own developments. While studying the materials, the authors considered such indicators as: prices for “Brent”and “Urals” oil, their relationship and the reasons for the fall in prices for gasoline and hydrocarbon-derived materials, as well as the impact on the prices of goods in other economic sectors. The paper studies and selects the most effective responses to changes in the market environment in the context of nonstationary fuel prices.

scholarly journals Bending–torsional-coupled vibrations and buckling characteristics of single and double composite Timoshenko beams

2019 ◽  
Vol 11 (3) ◽  
pp. 168781401983445
Author(s):  
Ma’en S Sari ◽  
Wael G Al-Kouz ◽  
Rafat Al-Waked
Keyword(s):  
Slenderness Ratio ◽  
Equations Of Motion ◽  
Mode Shapes ◽  
Timoshenko Beams ◽  
Engineering Structures ◽  
Axial Forces ◽  
Double Beam ◽  
Tensile Forces ◽  
Torsional Coupling ◽  
The Stability

The stability and free vibration analyses of single and double composite Timoshenko beams have been investigated. The closed-section beams are subjected to constant axially compressive or tensile forces. The double beams are assumed to be connected by a layer of elastic translational and rotational springs. The coupled governing partial differential equations of motion are discretized, and the resulted eigenvalue problem is solved numerically by applying the Chebyshev spectral collocation method. The effects of the elastic layer parameters, the axial forces, the slenderness ratio, the bending–torsional coupling, and the boundary conditions on the critical buckling loads, mode shapes, and natural transverse frequencies have been studied. A parametric study was performed, and the obtained results revealed different features, which hopefully can be useful for single- and double-beam-like engineering structures.

scholarly journals Evolution Laws of Mining-induced Stress in Floor Strata and Its Influence on the Stability of a Floor Roadway Affected by Overhead Mining

2020 ◽  
Vol 24 (1) ◽  
pp. 45-54 ◽  
Author(s):  
Pu Wang ◽  
Lishuai Jiang ◽  
Changqing Ma ◽  
Anying Yuan
Keyword(s):  
Numerical Simulation ◽  
Mechanical Model ◽  
Scientific Basis ◽  
Pull Out ◽  
Induced Stress ◽  
Working Face ◽  
Geological Conditions ◽  
Evolution Laws ◽  
The Stability

The study of evolution laws of the mining-induced stress in floor strata affected by overhead mining is extremely important with respect to the stability and support of a floor roadway. Based on the geological conditions of the drainage roadway in the 10th district in a coalmine, a mechanical model of a working face for overhead mining over the roadway is established, and the laws influencing mining stress on the roadway in different layers are obtained. The evolution of mining stress in floor with different horizontal distances between the working face and the floor roadway that is defined as LD are examined by utilizing UDEC numerical simulation, and the stability of roadway is analyzed. The results of the numerical simulation are verified via on-site tests of the deformation of the surrounding rocks and bolts pull-out from the drainage roadway. The results indicate that the mining stress in floor is high, which decreases slowly within a depth of less than 40 m where the floor roadway is significantly affected. The mining stress in the floor increases gradually, and the effect of the mining on the roadway is particularly evident within 0 m ≤ LD ≤ 40 m. Although the floor roadway is in a stress-relaxed state, the worst stability of the surrounding rocks is observed during the range -20 m ≤ LD < 0 m, in which the negative value indicates that the working face has passed the roadway. The roadway is affected by the recovery of the abutment stress in the goaf when -60 m ≤ LD <20 m, and thus it is important to focus on the strengthening support. The results may provide a scientific basis for establishing a reasonable location and support of roadways under similar conditions.

Environmental Effects in Gel Derived Silicates

1984 ◽  
Vol 32 ◽  
Author(s):  
L.L. Hench
Keyword(s):  
Corrosion Resistance ◽  
Sol Gel ◽  
Glass Ceramics ◽  
Thermal Exposure ◽  
Scientific Basis ◽  
Environmental Stability ◽  
Processing Variables ◽  
End Use ◽  
The Stability ◽  
Gel Processing

Various methods have been developed for producing crystals, powders, coatings and monoliths from gels [1]. The scientific basis for understanding compositional effects, gelation, aging, drying and densification is also advancing rapidly [2]. However, there is as yet relatively little information on the durability, weathering, or corrosion resistance of glasses, glass-ceramics, ceramics, or composites made via the gel route. Data is also sparse on the effects of vacuum, thermal exposure, or mechanical stress on the stability of gel-derived solids. Relationships between sol-gel processing variables and environmental stability are especially lacking at the present time. Since many end-use applications of gel derived materials involve exposure to severe environments, it is essential that the durability of these materials be established during their development.

scholarly journals Study of the Stability of a Soil-Rock Road Cutting Slope in a Permafrost Region of Hulunbuir

2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
Yuxia Zhao ◽  
Jun Feng ◽  
Kangqi Liu ◽  
Hongwei Xu ◽  
Liqun Wang ◽  
...  
Keyword(s):  
High Latitude ◽  
Limit Equilibrium ◽  
Slope Angle ◽  
In Situ Monitoring ◽  
Permafrost Region ◽  
Freeze Thaw ◽  
Stability Of Slopes ◽  
Low Altitude ◽  
The Stability ◽  
Permafrost Regions

Due to the threat of global warming and the accelerated melting of glaciers and permafrost, the stability of slopes in permafrost regions has received an increasing amount of attention from scholars. However, research on the stability of soil-rock road cutting slopes in high-latitude and low-altitude permafrost regions of the Greater Khingan Mountains in the Inner Mongolia Autonomous Region has not been reported. For this reason, a study of the stability of a slope with a high ice content in section K105 + 600 to K105 + 700 of National Highway 332 is conducted. The slope is 20 m high and the slope angle is 45°, and the risk of landslides on this slope under the action of freeze-thaw erosion is very high. Because of this, field in situ monitoring, indoor freeze-thaw tests, thermal parameter tests, and ABAQUS numerical simulation models are used to study the stability of the slope. After collecting the continuous temperature, moisture, settlement, and slope deformation data, it was found that the slope was undergoing dynamic changes. The creep of shallow slopes increased with the number of freeze-thaw cycles. After approximately 150 freeze-thaw cycles, the slope safety factor was less than 1, which means that the slope had reached the limit equilibrium state. Therefore, freeze-thaw erosion greatly reduced the stability of the slope. Hence, the stability of the slope must be protected during its entire life cycle. This study provides a reference for the design and construction of road cutting slopes in the high-latitude and low-altitude permafrost regions of the Greater Khingan Mountains.

scholarly journals Optimization of the Extraction and Stability of Antioxidative Peptides from Mackerel (Pneumatophorus japonicus) Protein

2017 ◽  
Vol 2017 ◽  
pp. 1-14 ◽  
Author(s):  
Xueqin Wang ◽  
Huahua Yu ◽  
Ronge Xing ◽  
Xiaolin Chen ◽  
Song Liu ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Protein Hydrolysate ◽  
Scientific Basis ◽  
Enzyme Concentration ◽  
Scavenging Activity ◽  
Preparation Conditions ◽  
Low Concentrations ◽  
Dpph Scavenging Activity ◽  
Dpph Scavenging ◽  
The Stability

This study optimizes the preparation conditions for mackerel protein hydrolysate (MPH) by response surface methodology (RSM) and investigates the stability of the antioxidant activity of MPHs (<2.5 kDa). The optimal conditions were as follows: enzyme concentration of 1726.85 U/g, pH of 7.00, temperature of 39.55°C, time of 5.5 h, and water/material ratio of 25 : 1, and the maximum DPPH scavenging activity was 79.14%. The MPHs indicated significant cellular antioxidant activity at low concentrations. Furthermore, the temperature and freeze-thaw cycles had little effect on the antioxidative stability while pH had significant effect on the antioxidative stability. In addition, the MPHs were sensitive to the metal ions, such as Fe2+, Fe3+, Zn2+, and Cu2+. Notably, when the concentrations of Fe2+and Fe3+were 5 mM, the DPPH scavenging activities were only 1.1% and 0.6%, respectively; furthermore, Cu2+at a 5 mM concentration could completely inhibit the DPPH scavenging activity of MPHs. In contrast, K+and Mg2+had no notable effect on the antioxidant activity of MPHs. These results may provide a scientific basis for the processing and application of MPHs.

The Development of Device for On-Line Monitoring Circulating Cooling Water Stability

2014 ◽  
Vol 672-674 ◽  
pp. 1743-1747
Author(s):  
Li Qiang Zhang ◽  
Mo Jie Sun ◽  
Ting Zhang ◽  
Zhao Li ◽  
Huan Wei Wang
Keyword(s):  
Power Plants ◽  
Cooling Water ◽  
Stability Index ◽  
Scientific Basis ◽  
Water Quantity ◽  
Water Stability ◽  
Circulating Cooling Water ◽  
On Line ◽  
The Stability ◽  
And Control

China is a country lacking of freshwater. With the water pollution from bad to worse, saving water become a serious matter which needs to be settled at once. In order to ensure the system working safely and the water quality, most power plants enable the circle cooling water to work in the low consistence, need more drainage and complement water which will make large waste of water. The good water quantity means that the water doesn’t make the furring and make cautery to the equipment. So we can improve the concentrated multiples of the cycle cooling water to save the water. Based on the specialty of the water used in the power plants, this subject study how to estimate the stability, doing the instrument and watching the stability degree, providing the scientific basis for disposing the circling water. After lots of experiments, we use the stability index as the estimation and use the pH determination as the alkalinity determination.The instrument uses the date collecting card to collect and use computer to dispose the date and control the instrument. The system inspects the stability of the cycle cooling water real time automatically.

The Research of Slope Stability Based on Unsaturated Soil Theory

2014 ◽  
Vol 937 ◽  
pp. 590-593
Author(s):  
Chang Qing Shao ◽  
Nan Zhang ◽  
Feng Lan Lv
Keyword(s):  
Unsaturated Soil ◽  
Evaluation Methods ◽  
Rainfall Infiltration ◽  
Stability Factor ◽  
Analysis Method ◽  
Infiltration Process ◽  
Strong Activity ◽  
The Matrix ◽  
Matrix Suction ◽  
The Stability

With the deep landslide induced by rainfall or more in practice, the existing evaluation methods are not suitable for to explain this kind of landslide during rainfall, which is the phenomenon of strong activity. This paper tries to improve existing methods for analyzing the stability of the landslide, the article set up to consider soil stability analysis method of the matrix suction side article discusses rainfall infiltration process middle side matrix suction changes impacting on the stability of the landslide, the preliminary discussion on the effect of rainfall on deep landslide are studied. Considering soil of the side of the evaluation methods of matrix suction jettisoned traditional saturated unsaturated soil mechanics analysis method, it can well reflect the process of rainfall infiltration, the matrix suction decreases, and the inter-atomic forces, stability factor to reduce the process, providing a train of thought for landslides evaluation.

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