scholarly journals Creation of a Device for Testing of the Rock Samples for Gap in Volumetric Compression Chamber

2020 ◽  
Vol 174 ◽  
pp. 01007
Author(s):  
Svetlana Kostyuk ◽  
Nikolay Bedarev ◽  
Oleg Lyubimov ◽  
Yunliang Tan
Keyword(s):  
Compressive Strength ◽  
Internal Friction ◽  
Angle Of Internal Friction ◽  
Rock Samples ◽  
Volume Compression ◽  
Host Rocks ◽  
Compression Chamber

A device for the volume compression chamber of the samples is described and some possibilities for testing the samples are presented: compressive strength, angle of internal friction, and adhesion values of coal and host rocks. In addition, descriptions of patents for devices allowing to test rocks for breaking during volume compression are given.

scholarly journals Models for evaluating craters morphology, relation of indentation hardness and uniaxial compressive strength via a flat-end indenter

2018 ◽  
Vol 10 (1) ◽  
pp. 289-296 ◽  
Author(s):  
Ligang Zhang ◽  
Xiao Fei Fu ◽  
G. R. Liu ◽  
Shi Bin Li ◽  
Wei Li ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Internal Friction ◽  
Uniaxial Compressive Strength ◽  
Poisson’S Ratio ◽  
Failure Process ◽  
Apex Angle ◽  
Poisson's Ratio ◽  
Percentage Error ◽  
Indentation Hardness ◽  
Angle Of Internal Friction

AbstractIn this work, the intensive theoretical study and laboratory tests are conducted to evaluate the craters morphology via the flat-ended indenter test, relationship of indentation hardness (HRI) and uniaxial compressive strength (UCS). Based on the stress distribution, failure process and Mohr–Coulomb failure criterion, the mathematical mechanical models are presented to express the formation conditions of “pulverized zone” and “volume break”. Moreover, a set of equations relating the depth and apex angle of craters, the ratio of indentation hardness and uniaxial compressive strength, the angle of internal friction and Poisson’s ratio are obtained. The depth, apex angle of craters and ratio of indentation hardness and uniaxial compressive strength are all affected by the angle of internal friction and Poisson’s ratio. The proposed models are also verified by experiments of rock samples which are cored from Da Qing oilfield, the percentage error between the test and calculated results for depth, apex angle of craters and the ratio of HRI and UCS are mainly in the range of –1.41%–8.92%, –5.91%–3.94% and –8.22%–13.22% respectively for siltstone, volcanic tuff, volcanic breccia, shale, sand stone and glutenite except mudstone, which demonstrates that our proposed models are robust and effective for brittle rock.

scholarly journals Geomechanical Characteristics And Failure Analysis of The Limestone Slope At Sahastradhara-Chamasari Road Dehradun Uttarakhand India

2021 ◽  
Author(s):  
Nirlipta Priyadarshini Nayak ◽  
Harinandan Kumar ◽  
Ashish Aggarwal ◽  
Muralidhar Singh M.
Keyword(s):  
Compressive Strength ◽  
Internal Friction ◽  
Failure Analysis ◽  
Slope Failure ◽  
Axial Strain ◽  
Core Sample ◽  
Loading Conditions ◽  
Angle Of Internal Friction ◽  
The Core ◽  
Limestone Rock

Abstract In this study, the rock slope failure analysis was carried out to predict the stability of the limestone rock in the Sahastradhara-Chamasari Road Dehradun Uttarakhand, India. The limestone rock samples were collected from the study area for testing purposes. The geomechanical parameters like compressive strength, axial strain, young’s modulus, cohesive strength, angle of internal friction, etc., were experimentally determined to study their application in the simulation of slope failure analysis. A 2D model of the study area was developed using the field data for modelling and simulation purposes. Slope failure analysis was carried out using the Finite element method (FEM). Results indicated maximum compressive strength of the core sample as 85.14 MPa while axial strain and elastic modulus were 0.02197 and 842.45 MPa, respectively. The cohesive strength and the angle of internal friction of the core sample were evaluated as 38.59 kPa and 12.96 degree. The slope failure analysis was carried out to determine the factor of safety (FOS) of the slope at variable loading conditions. A decreasing trend of the FOS was observed with loading. The lesser value of FOS at higher loading conditions required the supporting system at the foot level of the slope for the slope stability in the study area.

scholarly journals Investigations on Improving the Compressive Strength of Sand Column with Cement Grout and Chemical Admixture

2021 ◽  
Vol 12 (2) ◽  
pp. 1841-1847
Author(s):  
M. Samuel Thanaraj, Et. al.
Keyword(s):  
Compressive Strength ◽  
Internal Friction ◽  
Water Content ◽  
Soil Improvement ◽  
Cement Grout ◽  
Sand Column ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Angle Of Internal Friction ◽  
Chemical Admixture

Grouting is one of the most commonly adopted technique for soil improvement and strengthening. Adding super plasticizers, accelerators, antifreezes, air entraining agent improves the performance of the cement grout. The performance of the grout while injecting in the sand column mainly depends on its fluidity property.  Keeping it in mind about the water cement ratio, the strength of the sand column is studied in two sets of experiments one by sand column with cement grout only and another set by sand column with cement grout added with super plasticizers by varying the water cement ratios. Strength parameters like angle of internal friction and cohesion were obtained be direct shear test and unconfined compressive strength test on the specimens by varying the water content. An increase of 15.2kPa to 60.33 kPa was observed in the cohesion value for specimens with 10% water content and 13.8 kpa to 47.2kPa cohesion value observed in the specimens with 20% water content. The angle of internal friction was decreased from 360 to 160 for 10% water content whereas 300 to 100 for 20% water content.  A series of experiments were conducted on the sand column grouted with cement and for different water cement ratios as 1.5, 2.0 and 2.5. Another set of experiments were repeated by adding 2%super plasticizer Sulphonated Melamine Formaldehyde (SMF). The experiment results revealed that at lower water cement ratio higher value of compressive strength was observed. It was also observed that the strength increases with curing period. 

scholarly journals Shear strength characteristics of Jerash expansive soil

2021 ◽  
Vol 3 (2) ◽  
pp. 74-80
Author(s):  
Talal Masoud
Keyword(s):  
Shear Strength ◽  
Internal Friction ◽  
Water Content ◽  
Direct Shear Test ◽  
Shear Test ◽  
Expansive Soil ◽  
Content Increase ◽  
Direct Shear ◽  
Initial Water ◽  
Angle Of Internal Friction

The results of the direct shear test on Jerash expansive soil show the effect of the initial water content on the cohesion (c) and on the angel of internal friction ( ) [shear strength parameters].it show that, as the initial water increase, the cohesion (c) of Jerash expansive soil also increase up to the shrinkage limit, after that increase of water even small amount, decrease the cohesion of the soil. On the other hand, the results of direct shear test show also  that as the water content increase, the angle of internal friction ( )remain unchanged up to shrinkage limit , any increase of water cause a large decrease on the angle of internal friction of Jerash expansive soil.

scholarly journals Multivariate Analyses of Selected Mechanical Properties of Dry Bean Grain

2015 ◽  
Vol 29 (2) ◽  
pp. 175-183 ◽  
Author(s):  
Hakan Kibar
Keyword(s):  
Principal Component Analysis ◽  
Internal Friction ◽  
Lateral Pressure ◽  
Bulk Material ◽  
Poisson Ratio ◽  
Pressure Ratio ◽  
Principal Component ◽  
Component Analysis ◽  
Dry Bean ◽  
Angle Of Internal Friction

Abstract The direct shear test are widely used to measure the bulk material properties for economical design of bulk handling equipment and to estimate wall pressure inside storage structures, namely their bulk density, the angle of internal friction, shear strength, Poisson ratio, and lateral pressure ratios are required. Tests were conducted at thirty six different shear speeds (between 0.30-1.00 mm min-1) and three different normal stresses were applied (60, 120 and 180 kPa). The angle of internal friction, Poisson ratio, and lateral pressure ratios demonstrated fluctuations depending on the shear speeds. The results of the principal component analysis indicated that the first three principal components accounted for 97.40% of the total variability among the thirty six different shear speeds for all the traits investigated. The first principal component was the most important. In the result of principal component analysis, the shear speeds were divided into seven clusters. The pressures were decreased and increased with the change of the angle of internal friction and the lateral pressure ratio. The data obtained from the study will be useful in the structural design of dry bean bins to calculate loads on bins from the stored material and grain handling equipment.

scholarly journals Flow and Thermal Properties of Stevia Powder

2018 ◽  
Vol 21 (2) ◽  
pp. 51-55 ◽  
Author(s):  
Ajit K. Mahapatra ◽  
Agnes J. Kapsoiyo ◽  
Sierra C. Birmingham ◽  
Daniel Ekefre ◽  
Bipul K. Biswas
Keyword(s):  
Thermal Properties ◽  
Internal Friction ◽  
Polynomial Regression ◽  
Stevia Rebaudiana ◽  
Calorific Value ◽  
Flow Index ◽  
Published Data ◽  
Mean Flow ◽  
Angle Of Internal Friction ◽  
The Mean

Abstract Stevia (Stevia rebaudiana Bertoni) has recently received a lot of attention as a sweetener due to its taste and low calorific value. Flow and thermal properties of foods play a significant role in the quantitative analysis of unit operations in the food industry. However, there are no published data available on flow and thermal properties of stevia powder. Powder Flow Tester and KD2 Pro Thermal Properties Analyzer were used to determine the flow and thermal properties of stevia powder, respectively, at different moisture contents (4.96%, 9.68%, 13.99%, 20.08%, and 25.79%, w.b.). Mean angle of internal friction of stevia powder ranged from 41.13° to 46.3°. The mean effective angle of internal friction ranged from 47.8° to 52.5° and the mean flow index ranged from 0.27 to 0.48. Mean thermal conductivity of stevia powder ranged from 0.091 W·m-2·K-1 to 0.115 W·m-2·K-1. Mean thermal diffusivity ranged from 0.103 mm2·s-1 to 0.121 mm2·s-1 and mean volumetric specific heat ranged from 0.865 MJ·m-3·K-1 to 1.019 MJ·m-3·K-1. Polynomial regression models were developed to predict flow and thermal properties of stevia powder using moisture content of stevia powder.

scholarly journals A Comparative Analysis of the Flow Properties between Two Alumina-Based Dry Powders

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Milene Minniti de Campos ◽  
Maria do Carmo Ferreira
Keyword(s):  
Internal Friction ◽  
Moisture Content ◽  
Ceramic Powder ◽  
Morphological Characteristics ◽  
Angle Of Repose ◽  
Wall Friction ◽  
Flow Index ◽  
Alumina Powder ◽  
Flow Properties ◽  
Angle Of Internal Friction

We measured and compared the flow properties of two alumina-based powders. The alumina powder (AP) is irregularly shaped and has a smooth surface and moisture content of 0.16% (d.b.), and the ceramic powder (CP), obtained after atomization in a spray dryer, is spherical and has a rough surface and moisture content of 1.07%. We measured the Hausner ratio (HR), the static angle of repose (AoR), the flow index (FI), the angle of internal friction, and the wall's friction angle. The properties measured using aerated techniques (AoR and HR) demonstrated that AP presents true cohesiveness (and therefore a difficult flow), while CP presents some cohesiveness and its flow might be classified as half way between difficult and easy flow. Their FI values, which were obtained using a nonaerated technique, enable us to classify the alumina as cohesive and the ceramic powder as an easy-flow powder. The large mean diameter and morphological characteristics of CP reduce interparticle forces and improve flowability, in spite of the higher moisture content of their granules. The angles of internal friction and of wall friction were not significantly different when comparing the two powders.

Sign in / Sign up

Export Citation Format

Share Document