scholarly journals Determination of the Boundaries of the Compressible Strata When Conducting Engineering Surveys

2020 ◽  
Vol 24 (3) ◽  
pp. 79-87
Author(s):  
K. O. Dubrakova ◽  
V. A. Solodilova
Keyword(s):  
Sandy Loam ◽  
Physical And Mechanical Properties ◽  
Fine Sand ◽  
Coarse Sand ◽  
Adequate Accuracy ◽  
Practical Standpoint ◽  
The Cost ◽  
The Given ◽  
Main Influence

Purpose of research. Errors and inaccuracies in the preparation of deliverables based on the results of engineering surveys which are an integral and important part of the design and estimate documentation, can lead to irreversible consequences and significantly reduce the life of buildings and structures. The main difficulty in investigating soil physical and mechanical properties at a construction site is to determine the depth of excavation. This is due to the fact that an increase in the calculated depth leads to the increase in the cost of work, and its decrease leads to the risk of inaccuracies and errors in the design of foundations of buildings and structures. In accordance with the current regulatory documents, the excavation depth during soil investigation should be 1-2 meters below the boundary of the compressible strata. The condition on the basis of which the specified boundary is determined is provided. The development of a technique that allows determining the depth of the compressible strata at the stage of engineering surveying with adequate accuracy is an important task from a practical standpoint. Methods. Determining natural stress Ϭzg,0 as the product of foundation depth d and the specific gravity of the soil above the base ɣ′ІІ,  , taking into account the fact that the average pressure tends to the value of the estimated resistance of the soil, it is shown that physical-mechanical structure of the base soil exerts the main influence on the parameters of the compressible strata, and correspondingly, to the excavation depth value. In this case, the stresses transferred by the foundation of a building or structure have an indirect effect. Results. The maximum values of the depth of excavation for engineering and geological surveying for tight coarse sand, medium density and fineness sand, and fine sand and sandy loam are determined. Conclusion. It is concluded that the given technique allows determining the depth of excavation during engineering and geological surveying with an adequate accuracy.

Determination of water content in drying soils: incorporating transition from liquid phase to vapour phase

Soil Research ◽  
2004 ◽  
Vol 42 (1) ◽  
pp. 1 ◽  
Author(s):  
F. Konukcu ◽  
A. Istanbulluoglu ◽  
I. Kocaman
Keyword(s):  
Water Content ◽  
Transition Zone ◽  
Sandy Loam ◽  
Vapour Phase ◽  
Coarse Sand ◽  
Arid Environments ◽  
Evaporation Front ◽  
Matric Potential ◽  
Silty Loam

In arid and semi-arid environments, soil profiles often exhibit a liquid–vapour displacement known as evaporation front characterised by a critical matric potential (ψme) or water content (θe) located somewhere inside the unsaturated zone above a watertable (WT). The objective of this study was to determine the θe including the range of water content (θ) in the transition zone from liquid to vapour both theoretically and experimentally for different soil textures under saline and non-saline WTs. Characteristic shapes of water content and salt concentration profiles were the criteria to obtain θe experimentally, and the θ–diffusivity relationship was used to compute the θe and θ range in the transition zone. Measured θe values of 0.05 and 0.12 m3/m3 under non-saline WT and 0.07 and 0.15 m3/m3 under saline WT were in agreement with the computed values of 0.05 and 0.10 m3/m3 for sandy loam and clay loam soils, respectively. The model calculates roughly the same θe for saline and non-saline conditions. Besides experimental soils, θe and range of θ in the transition zone were calculated for silty loam and coarse sand. The lighter the soil texture, the smaller is θe and the steeper the transition zone. The results were further compared with those calculated by different authors.

Effect of soil properties and soil disturbance on frost heaving of mineral soil: a laboratory experiment

2006 ◽  
Vol 36 (11) ◽  
pp. 2885-2893 ◽  
Author(s):  
Michelle de Chantal ◽  
Hannu Rita ◽  
Urban Bergsten ◽  
Mikaell Ottosson Löfvenius ◽  
Harald Grip
Keyword(s):  
Laboratory Experiment ◽  
Repeated Measures ◽  
Sandy Loam ◽  
Mineral Soil ◽  
Fine Sand ◽  
Soil Disturbance ◽  
Coarse Sand ◽  
Loamy Sand ◽  
Frost Heaving ◽  
C And N

A laboratory experiment was done to identify the properties that make a substrate susceptible to frost heaving. Tests were carried out on nondisturbed soil cores (fresh and dry) of Ae and B horizons from sand, loamy sand, and sandy loam in a freezing cabinet (–3.5 °C). Cores were continuously supplied with water from below. Freezing tests were repeated after soil disturbance (V-shaped furrow, 50% increase in surface area). The effects of texture, horizon, drying, and disturbance on frost heaving were tested using repeated-measures analysis of variance with soil elements (organic Al, organic Fe, inorganic Al, inorganic Fe, C, and N) and soil fractions (clay, fine silt, coarse silt, fine sand, and coarse sand) as covariates. The effect of horizon was as important as that of texture, and soil disturbance increased frost heaving. Disturbed fresh B horizon from loamy sand and sandy loam heaved the most (soil expansion >5% in height), whereas nondisturbed dry Ae horizon, regardless of texture, and nondisturbed dry B horizon from sand heaved the least (soil expansion <0.8% in height). Soil elements and fractions had an impact on frost heaving, especially organic Al, although it was of a smaller magnitude. Therefore, it is suggested that seedbeds or planting substrates be prepared by exposing the nondisturbed Ae horizon only, that is, without exposing or disturbing the B horizon.

scholarly journals Improving the operational efficiency of tractors by ensuring their ability to perform work

2020 ◽  
Vol 17 ◽  
pp. 00111
Author(s):  
Sergej Yahin ◽  
Fanil Gabdrafikov ◽  
Farit Khaliullin ◽  
Rail Khusainov ◽  
Insaf Naficov
Keyword(s):  
Working Conditions ◽  
Climatic Conditions ◽  
Industrial Complex ◽  
Technical Equipment ◽  
Actual Volume ◽  
Design Documents ◽  
The Cost ◽  
Market Relations ◽  
The Given

Development of agriculture in conditions of market relations is accompanied by aggravation of the problem of efficiency of use of technics. In this connection, the task of scientists is to increase the actual volume of work performed by tractor units, reducing the cost per unit of production. The high cost of tractors, the lack of personnel, the reduction of technical equipment of farms and the increase in the volume of products produced in the agro-industrial complex, natural and climatic conditions impose special requirements on technical service to maintain tractors in working conditions. The working state of tractors is the state at which values of parameters, which characterize ability to execute the given functions, correspond to normative-reference and design documents. During the operation of tractors in agriculture under the influence of various factors, wear of their parts and knots. The indicator determining the value of wear is the residual resource of aggregates and knots of technics. In the article the questions of influence of residual resources of basic aggregates and systems of tractor on frequency of failures of various groups of complexity are considered. Experimental research on determination of dependencies of residual resources of tractor units and frequency of failures of different groups of complexity, on the basis of which the rules of replacement of the unit whose resource are exhausted, is carried out, i.e. is replaced with a full of the resource (new) or on the aggregate after overhaul.

scholarly journals Method and equipment for the safe development of preparatory workings in the gas-bearing coal seams

2019 ◽  
Vol 109 ◽  
pp. 00102
Author(s):  
Mykola Trokhymets ◽  
Vira Maltseva ◽  
Yehor Vialushkin ◽  
Volodymyr Antonchik ◽  
Tetiana Moskalova ◽  
...  
Keyword(s):  
Coal Seam ◽  
Mathematical Models ◽  
Mining Operations ◽  
Liquid Injection ◽  
Mathematical Formulas ◽  
Outburst Coal Seam ◽  
The Cost ◽  
The Given ◽  
Gas Bearing

The article describes a method and equipment for the safe development of preparatory working on a gas-bearing, outburst hazardous coal seam by a heading machine. The described method significantly prevents the gas emission during mining operations. Determination of the amount of degassing and relief wells is performed according to the given in article mathematical formulas. This ensures a significant increase in the level of safety processing the preparatory roadway on a gas-bearing, prone to outbursts coal seam by a heading machine. Due to this, the speed of conducting excavation increases and the cost of mining is reduced. The proportionality coefficients of the mathematical models were determined. Mathematical models are used to calculate the number of relief and degassing wells, which are drilled during the impulse hydraulic loosing of the nearby part of the coal seam. Also the duration of liquid injection into a coal seam is also determined. Mathematical models for calculating the number of injection, unloading and degassing boreholes can be used in development of the passports for conducting preparatory workings on a gas-bearing, prone to outburst coal seam by a heading machine with a preliminary impulse hydraulic loosing of the nearby part of a coal seam.

scholarly journals Determination of economically viable option of liquidation the consequences of external dump deformation

2021 ◽  
Vol 280 ◽  
pp. 08014
Author(s):  
Yevheniy Babets ◽  
Oleh Anisimov ◽  
Oleksandr Shustov ◽  
Vitalina Komirna ◽  
Iryna Melnikova
Keyword(s):  
Mechanical Properties ◽  
Physical And Mechanical Properties ◽  
Safety Factors ◽  
Viable Option ◽  
The Third ◽  
The Stability ◽  
The Cost ◽  
Technical And Economic Indicators ◽  
Processing Enterprise

The safety factors for different variants of operation development were obtained, on the basis of which the technical and economic indicators were established and the most expedient way of restoration of dump operations in conditions of the formed landslide was chosen. The solutions were proposed for the external dump No 2 of the Central Ore Mining and Processing Enterprise (COMPE), that allow to continue its future operation. When working in the conditions of the formed landslide, three variants of the further dump operation are modeled: the first one - with landslide removal and unloading of the upper dump horizons, the second one - without landslide removal and involvement of disturbed lands in land allotment, the third one - with the landslide loading. Based on the built sections of the dump and defined physical and mechanical properties, the stability factors were obtained for different options of the operation development, which made it possible to determine the appropriate option to eliminate the effects of the dump slide deformations. As a result of the calculations, the cost flows for each of the proposed options of the formation of the end contour of the dump No 2 are determined.

scholarly journals Fabrication of Permeameter for Determination of Hydraulic Conductivity of Earth Materials

2020 ◽  
Vol 9 (4) ◽  
pp. 1204-1210
Keyword(s):  
Hydraulic Conductivity ◽  
Engineering Design ◽  
Low Cost ◽  
Pressure Head ◽  
Fine Sand ◽  
Coarse Sand ◽  
Silty Clay ◽  
Earth Dams ◽  
Soil Hydraulic Conductivity

Laboratory investigation is one of the major ways of assessing soil hydraulic conductivity. Determination of hydraulic conductivity aids in engineering design of well pumping, prediction concerning spread of polluting fluids, embankment of canal bank affected by seepage, flooding solutions and stability of earth dams. However, different studies have shown that there are alternative models to Darcy’s law which governs the widely use of laboratory measurement of hydraulic conductivity. The deficiencies accustomed to the conventional permeameter such as the time wastage and cost-intensivehas led to different research modification. A low-cost permeameter was fabricated using a plastic column, hose pipe, to serve as water inlet and outlet connected to two manometer tubes to measure the pressure head difference. The hydraulic conductivities measured using the lowcost were 4.31 cm/s, 8.14 cm/s, 6.12 cm/s, 5.86 cm/s for 0.3 mm coarse sand, 0.85-1 mm fine sand, sandy clay and silty clay respectively. In comparison of the fabricated permeameter with conventional permeameter and other fabricated laboratory permeameters, it was observed that the hydraulic conductivity obtained is consistent with the typical permeability range for each soil type.

scholarly journals PEDOGENESIS ON COASTAL TABLELANDS AREA WITH LOW RANGE ALTIMETRY IN PARAÍBA STATE

2019 ◽  
Vol 32 (2) ◽  
pp. 458-471
Author(s):  
GIVANILDO ALVES DA SILVA ◽  
DANILO DE LIMA CAMÊLO ◽  
MARCELO METRI CORRÊA ◽  
VALDOMIRO SEVERINO DE SOUZA JÚNIOR ◽  
MATEUS ROSAS RIBEIRO FILHO ◽  
...  
Keyword(s):  
Ammonium Oxalate ◽  
Soil Classification ◽  
Fine Sand ◽  
Coarse Sand ◽  
Mineral Phases ◽  
Taxonomic Criterion ◽  
Physical And Chemical ◽  
Analysis Determination

ABSTRACT Small variations of relief may change drainage and runoff and hence promote the formation of sandy surface horizons and hardened subsurface horizons (fragipans and/or duripans) in Coastal Tablelands soils. This study aimed to investigate the pedogenesis on Coastal Tablelands area with low range altimetry in Paraíba state; secondly, we also sought to contribute to the improvement of the Brazilian Soil Classification System (BSCS). Four soil profiles ware described and collected to be submitted to routine physical and chemical analysis, determination of Fe, Al and Si extracted by sulfuric acid digestion, sodium citrate-bicarbonate-dithionite and acid ammonium oxalate, sodium pyrophosphate, and mineralogical analysis in the sand and clay fractions by X-ray diffractometry. Optical density of the oxalate extract (ODOE) was also determined; the results were statistically evaluated using the R software. Microrelief variations conditioning differentiated water flows, along with the sandy texture of the surface horizons (A and E) and the lower coarse sand/fine sand ratio in the subsurface horizon, seem to promote clay accumulation in depth in the Spodosols developed on Coastal Tablelands environments. For this soils, the argilluvic (argissólico) character at the subgroup level of the BSCS should be incorporated. In addition, Al amorphous mineral phases and/or poorly crystalline play an important role in the formation of strongly cemented horizons (duripans) of the Spodosols, as also reported by other authors. Finally, the ODOE showed to be an efficient indicator of soils under podzolization process, being possible its use as a taxonomic criterion for classification of Spodosols by the BSCS.

Mekanisme Dan Proteksi Jaminan Nasabah Pada Gadai Informal

Liquidity ◽  
2017 ◽  
Vol 6 (2) ◽  
pp. 103-109
Author(s):  
Yuri Nanda Larasati ◽  
Jafril Khalil
Keyword(s):  
Qualitative Research ◽  
Research Methods ◽  
Financial Services ◽  
Field Data ◽  
Qualitative Research Methods ◽  
Research Field ◽  
Consumer Society ◽  
Library Research ◽  
The Cost

Regulation of the financial services authority (OJK) No. 31/POJK.05/2016 on Venture had arranged that the financial services agency on the basis of the law of pledge is in coaching and supervision OJK. Yet the existence of laws – invitation to Governing Enterprise pawn shops causing business activities conducted by the above parties are not yet regulated. The condition is feared could cause harm to the consumer society. The purpose of this research is to know the procedures, mechanisms, protection of goods and guarantee the consumer on an informal pledge financing, methods of determination of the cost of maintenance of the goods and the goods of the execution mechanism of the pledge as well as protection for the collateral items are viewed from the side of the consumer by looking at laws-invitations and Sharia. To find out whether the pledge have gotten permission from OJK. This research uses qualitative research methods with the study of library research, field data and simulations. The approach used in this study is the empirical juridical approach. Elaboration upon the results is discussed further in this article.

The Role and Place of Budget Procedure in the System

2003 ◽  
pp. 42-49 ◽  
Author(s):  
E. Bushmin
Keyword(s):  
Budget Process ◽  
Public Expenditures ◽  
Principal Role ◽  
Process Trends ◽  
The Given ◽  
Rules Of The Game

The article is devoted to the analysis of improving budget process trends. The author offers the concept of "financial technologism". Its usage should promote an essential improvement of the budget process. The given concept is based on the fact that the regulation of budget procedure is the process of determination of "rules of the game", and the order of interaction of different institutions within the framework of the budget process, and the trends and volumes of expenses are the strategy of institutions. The procedure within the budget process plays a principal role as compared with the trends and volumes of public expenditures.

Determination of Combined and Second Order Factor Effects for Simultaneous Optimization of Physical and Mechanical Properties of NR/BR Blend System

2014 ◽  
Vol 42 (4) ◽  
pp. 290-304
Author(s):  
Rajarajan Aiyengar ◽  
Jyoti Divecha
Keyword(s):  
Physical And Mechanical Properties ◽  
Second Order ◽  
Simultaneous Optimization ◽  
Order Effects ◽  
Elongation At Break ◽  
Five Factors ◽  
Rubber Compounds ◽  
Polybutadiene Rubber ◽  
Contour Plots

ABSTRACT The blends of natural rubber (NR), polybutadiene rubber (BR), and other forms of rubbers are widely used for enhancing the mechanical and physical properties of rubber compounds. Lots of work has been done in conditioning and mixing of NR/BR blends to improve the properties of its rubber compounds and end products such as tire tread. This article employs response surface methodology designed experiments in five factors; high abrasion furnace carbon black (N 330), aromatic oil, NR/BR ratio, sulfur, and N-oxydiethylene-2-benzothiazole sulfenamide for determination of combined and second order effects of the significant factors leading to simultaneous optimization of the NR/BR blend system. One of the overall optimum of eight properties existed at carbon 44 phr, oil 6.1 phr, NR/BR 78/22 phr with the following values of properties: tensile strength (22 MPa), elongation at break (528%), tear resistance (30 kg/mm), rebound resilience (67%), moderate hardness (68 International rubber hardness degrees) with low heat buildup (17 °C), permanent set (12%), and abrasion loss (57 mm3). More optimum combinations can easily be determined from the NR/BR blend system models contour plots.

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