scholarly journals Determination of engineering properties of soil on railway track routes (An example of Turkey between the cities of Sivas and Erzincan)

2017 ◽  
Vol 6 (4) ◽  
pp. 337-349 ◽  
Author(s):  
Sevda Gören ◽  
Kenan Gelisli
Keyword(s):  
Railway Track ◽  
Engineering Properties ◽  
Properties Of Soil

Electrical Resistivity Based Non-Destructive Testing Method for Determination of Soil’s Strength Properties

2012 ◽  
Vol 488-489 ◽  
pp. 1553-1557 ◽  
Author(s):  
Fahad Irfan Siddiqui ◽  
Syed Baharom Azahar Bin Syed Osman
Keyword(s):  
Electrical Resistivity ◽  
Soil Disturbance ◽  
Strength Properties ◽  
Engineering Properties ◽  
Unit Weight ◽  
Ongoing Research ◽  
Electrical Resistivity Survey ◽  
Resistivity Survey ◽  
Properties Of Soil

Precise determination of engineering properties of soil is essential for proper design and successful construction of any structure. The conventional methods for determination of engineering properties are invasive, costly and time-consuming. Electrical resistivity survey is an attractive tool for delineating subsurface properties without soil disturbance. Reliable correlations between electrical resistivity and other soil properties will enable us to characterize the subsurface soil without borehole sampling. This paper presents the preliminary results of an ongoing research on correlations of electrical resistivity with strength properties of soil. Soil investigations, field electrical resistivity survey (VES) and laboratory electrical resistivity measurements were conducted. From the data analysis, significant correlations have been obtained between resistivity and moisture content and angle of internal friction. Weaker correlations have been observed for cohesion and unit weight of soil.

Tribology of rail bogie

2018 ◽  
Vol 77 (4) ◽  
pp. 230-240
Author(s):  
D. P. Markov
Keyword(s):  
Contact Fatigue ◽  
Basic Element ◽  
Difficult Problem ◽  
Railway Track ◽  
Rolling Stock ◽  
Kinematic Parameters ◽  
Approximate Estimation ◽  
Railway Bogie ◽  
Classical Calculation

Railway bogie is the basic element that determines the force, kinematic, power and other parameters of the rolling stock, and its movement in the railway track has not been studied enough. Classical calculation of the kinematic and dynamic parameters of the bogie's motion with the determination of the position of its center of rotation, the instantaneous axes of rotation of wheelsets, the magnitudes and directions of all forces present a difficult problem even in quasi-static theory. The paper shows a simplified method that allows one to explain, within the limits of one article, the main kinematic and force parameters of the bogie movement (installation angles, clearance between the wheel flanges and side surfaces of the rails), wear and contact damage to the wheels and rails. Tribology of the railway bogie is an important part of transport tribology, the foundation of the theory of wheel-rail tribosystem, without which it is impossible to understand the mechanisms of catastrophic wear, derailments, contact fatigue, cohesion of wheels and rails. In the article basic questions are considered, without which it is impossible to analyze the movement of the bogie: physical foundations of wheel movement along the rail, types of relative motion of contacting bodies, tribological characteristics linking the force and kinematic parameters of the bogie. Kinematics and dynamics of a two-wheeled bogie-rail bicycle are analyzed instead of a single wheel and a wheelset, which makes it clearer and easier to explain how and what forces act on the bogie and how they affect on its position in the rail track. To calculate the motion parameters of a four-wheeled bogie, it is represented as two two-wheeled, moving each on its own rail. Connections between them are replaced by moments with respect to the point of contact between the flange of the guide wheel and the rail. This approach made it possible to give an approximate estimation of the main kinematic and force parameters of the motion of an ideal bogie (without axes skewing) in curves, to understand how the corners of the bogie installation and the gaps between the flanges of the wheels and rails vary when moving with different speeds, how wear and contact injuries arise and to give recommendations for their assessment and elimination.

Geotechnical Applications of Sewage Sludge Stabilized with Biomass Ash and its Effect on Soil Nutriential Properties: A Critical Review

2021 ◽  
Vol 9 (VI) ◽  
pp. 1046-1051
Author(s):  
Ishowriya Yumnam
Keyword(s):  
Sewage Sludge ◽  
Positive Impact ◽  
Chemical Properties ◽  
Past Research ◽  
Biological Properties ◽  
Engineering Properties ◽  
Biomass Ash ◽  
The Past ◽  
Waste Sewage Sludge ◽  
Properties Of Soil

In this review article the usage of waste sewage sludge and the biomass ash for improving the engineering and non-engineering properties’ of both concrete and soil are discussed in detail. Numerous past research works were studied in detail so as to predict the behavior of biomass ash and waste sewage sludge when used for the stabilization process of soil and concrete. Past studies related to the usage of stabilized sewage sludge and biomass ash were studied in a detailed manner and depending upon the past studies several conclusions has been drawn which are discussed further. Several studies related to the usage of the waste sewage sludge for improving soil physical, chemical and biological properties showed that the usage of waste sewage sludge improve the physical properties, chemical properties, macro-nutriential properties and micro-nutriential properties up to a great extent. Depending upon the results of the past studies it can be concluded that the usage of sewage sludge has positive impact over all the properties of soil and this waste should be utilized in improving the properties of soil rather than dumping. Numerous studies related to the usage of the biomass ash showed that biomass ash has positive impact over both soil as well as concrete. Studies related to the usage of the biomass ash in soil showed that there was a positive response of the stabilized soil after its stabilization with the biomass ash. Studies related to the usage of the biomass ash in concrete showed that the biomass ash can be used up to 10 percent replacement of the ordinary Portland cement so as to attain maximum strength results from it.

scholarly journals The Valance Determination of Cerium Ions in α-SiAlON by Electron Energy Loss Spectroscopy Analysis

2008 ◽  
Vol 14 (S3) ◽  
pp. 19-22 ◽  
Author(s):  
H. Yurdakul ◽  
S. Turan
Keyword(s):  
Rare Earth ◽  
Ionic Radius ◽  
High Hardness ◽  
Engineering Properties ◽  
Secondary Phases ◽  
Sintering Additive ◽  
Valence States ◽  
Domain Boundaries ◽  
Spark Plasma

SiAlON ceramics have found applications in many different areas due to their excellent engineering properties such as high hardness, fracture toughness, good thermal shock and oxidation resistance. SiAlON exist mainly in two different polymorphs: a (MxSi12-(m+n)Al(m+n)OnN16-n; M: metal and rare earth cations, x≈0,35 and n≤1,35) and β (β-Si6-zAlzOzN8-z; 0≤z≤4). In general, stable alpha and beta phases separately as well as in combination of α and β are obtained by incorporation of metal and rare earth cations as sintering additives. The metal cations such as Li, Mg, Ca, Y, and most lanthanide cations with the exception of La, Ce, Pr and Eu are able to stabilise α-SiAlON structure. Ekstrom et al. 1991 found that cerium can not occupy interstitial sites in α-SiAlON structure due to the fact that ionic radius of Ce3+ (0.103 nm) is too large, whereas ionic radius of Ce4+ (0.080 nm) is too small to stabilise α-SiAlON structure. After this work, several studies carried out to incorporate cerium cations into α-SiAlON structure. It was shown that cerium cation alone can be incorporated into α-SiAlON if the samples are either fast cooled after sintering, or when the samples are spark plasma sintered. On the other hand, cerium can also be incorporated into the α-SiAlON structure when it is used as a sintering additive together with a smaller α-SiAlON stabiliser cation such as Yb or Ca. Similar results were observed in other multi-cation doped SiAlONS that non α-SiAlON stabiliser cations like Sr2+ (0.112 nm) and La3+ (0.106 nm) are able to stabilise α-SiAlON when used together with α-SiAlON stabiliser cations such as Ca or Yb. Although it was shown that cerium existed in mixed valance state at domain boundaries in Ce-doped and spark plasma sintered α-SiAlON, there is no work on the valance determination of cerium in sintered α-SiAlON which has no domain boundaries. Therefore, in this study; it was aimed to incorporate cerium into α-SiAlON structure by combining with Yb3+ and the determination of possible cerium valence states (Ce3+/Ce4+) in both α-SiAlON grains and secondary phases.

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