Effects of Water Content and Shearing Rate on Residual Shear Stress

2019 ◽  
Vol 44 (10) ◽  
pp. 8915-8929 ◽  
Author(s):  
Yanchao Wang ◽  
Lu Cong
Keyword(s):  
Shear Stress ◽  
Water Content ◽  
Shearing Rate ◽  
Residual Shear Stress

Characterization of Shear Strength and Interface Friction of Organic Soil

2020 ◽  
Vol 857 ◽  
pp. 203-211
Author(s):  
Majid Hamed ◽  
Waleed S. Sidik ◽  
Hanifi Canakci ◽  
Fatih Celik ◽  
Romel N. Georgees
Keyword(s):  
Shear Stress ◽  
Shear Strength ◽  
Internal Friction ◽  
Moisture Content ◽  
Water Content ◽  
Friction Angle ◽  
Structural Materials ◽  
Organic Soil ◽  
Internal Friction Angle ◽  
Interface Friction

This study was undertaken to investigate some specific problems that limit a safe design and construction of structures on problematic soils. An experimental study was carried out to examine the influence of loading rate and moisture content on shear strength of organic soil. Influece of moisture content on interface friction between organic soil and structural materials was also attempted. A commonly used soil in Iraq was prepared at varying moisture contents of 39%, 57% and 75%. The experimental results showed that the increase in water content will decrease the shear stress and the internal friction angle. An increase of the shearing rate was found to decrease the shear stress and internal friction angle for all percetanges of water contents. Further, direct shear tests were carried out to detect the interface shear stress behavior between organic soil and structural materials. The results revealed that the increase in water content was shown to have significant negetavie effects on the interface internal friction and angle shear strength.

scholarly journals Distribution Pattern of Anchorage Stress and Water Sensitivity Analysis of Red Clay

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Lifeng Li ◽  
Weili Gong ◽  
Huilin Deng ◽  
Xiaohu Zhang ◽  
Gan Li
Keyword(s):  
Shear Stress ◽  
Shear Strength ◽  
Distribution Pattern ◽  
Water Content ◽  
Exponential Distribution ◽  
Red Clay ◽  
Anchor Cable ◽  
Water Sensitivity ◽  
The Relationship ◽  
Single Exponential

Red clay is a special soil layer with complex engineering properties distributed in tropical and subtropical regions. An anchor cable support is a common form of red clay slope support. The effectiveness of the anchor cable support is mainly determined by the anchoring force provided by the red clay stratum. Increase of the water content will lead to the rapid deterioration of the mechanical properties of red clay, which will lead to the reduction of the anchoring force of the slope anchor cable and lead to the failure of the support. Based on the classical Phillips and uniform anchorage shear stress distribution theory, this paper puts forward a uniform-exponential distribution pattern of anchorage shear stress according to the specific characteristics of red clay by using the characteristics of the peak shear strength and residual shear strength of the rock and soil mass. With increasing anchorage force, the dynamic evolution (single exponential distribution ⟶ double single exponential distribution ⟶ uniform index exponential complex distribution ⟶ uniform distribution) of the anchorage shear stress is analysed. Based on the peak and residual test of the cohesive force and internal friction angle, the relationship between the anchoring force and buried depth and water content is established by analysing the factors influencing the anchoring force. It can be found from the field test that, according to the relationship established, the limit anchorage force of the anchor cable in the red clay stratum can be calculated and the water sensitivity of the anchor cable’s limit anchorage force can be quantitatively analysed.

Compaction and flow of potato starch and potato granules Compactación y flujo de almidón de patata y gránulos de patata

1997 ◽  
Vol 3 (5) ◽  
pp. 333-342 ◽  
Author(s):  
P.J. Halliday ◽  
A.C. Smith
Keyword(s):  
Shear Stress ◽  
Shear Rate ◽  
Wall Shear Stress ◽  
Water Content ◽  
Capillary Flow ◽  
Potato Starch ◽  
Slip Flow ◽  
Shear Stresses ◽  
Wall Shear ◽  
Water Contents

Potato starch and potato granules are materials that are often used in extrusion processes. It is important to quantify their rheology for modelling and prediction of process performance. The compaction behaviour of potato starch was examined at water contents of 4-18% wwb (wet weight basis) for pressures between 1 and 85 MPa. The Heckel deformation stress decreased as the water content increased up to 12% but became inaccurate at 18%. This decrease agreed qualitatively with other observations of the decrease in stiffness of starchy materials over this water content range. Potato granules were examined at water contents of 25-45% wwb and aspects of their rheo logical behaviour characterized using different approaches. A first approximation used the shear viscosity-shear rate power law which produced a law exponent for the resulting pastes (0.1-0.2). The classical Benbow equation was used to estimate yield and wall shear stresses in capillary flow. The latter indicates the presence of slip which was examined more fully as a function of wall shear stress. The Mooney technique was used together with a variation of the method where the shear rate for each die was subtracted from that for a non-slip flow, which was approximated using rough dies. A critical wall shear stress for slip was found to be 0.05-0.1 MPa, making it consistent with published results for other materials.

scholarly journals Starch Gelatinization under Shearless and Shear Conditions

2007 ◽  
Vol 2 (5) ◽  
Author(s):  
Fengwei Xie ◽  
Hongshen Liu ◽  
Pei Chen ◽  
Tao Xue ◽  
Ling Chen ◽  
...  
Keyword(s):  
Shear Stress ◽  
Water Content ◽  
Lipid Content ◽  
New Technology ◽  
Starch Gelatinization ◽  
Advantages And Disadvantages ◽  
Definition Of ◽  
Shear Condition ◽  
Detection Technologies

This article reviews the development of studying starch gelatinization under shear and shearless conditions, in particular the technologies used to detect the degree of gelatinization. Advantages and disadvantages of each technology were discussed and then some examples were presented to demonstrate their application. A new technology RheoScope, an instrument that can measure viscosity under shear stress and simultaneously observes variation of starch particles using a microscope, was also introduced. It was found the definition of "gelatinization" could be different for different detection technologies. Under shearless condition full gelatinization of starch needs about ratio of water 3/starch 1, while the gelatinization under shear condition requires less water content since shear stress enhances the processing. The number of endotherm and enthalpy of gelatinization depends on amylose/amylopectin, moisture and lipid content.

Fabrication of FSW Tool Pins Through Turning of H13 Tool Steel: A Comparative Analysis for Residual Stresses

2021 ◽  
pp. 1-16
Author(s):  
Ravi Butola ◽  
Ravi Pratap Singh ◽  
Naman Choudhary ◽  
K. K. S. Mer ◽  
Jitendra Bhaskar ◽  
...  
Keyword(s):  
Residual Stress ◽  
Shear Stress ◽  
Tool Steel ◽  
Compressive Residual Stress ◽  
Stress Measurement ◽  
Positive Impact ◽  
Cnc Machine Tools ◽  
Friction Stir ◽  
H13 Tool Steel ◽  
Residual Shear Stress

In the present research, measurement of residual stress induced during turning and threading operations for the fabrication of two types of pin profiled friction stir processing/welding (FSP/FSW) tools, i.e. cylindrical profiled pin tool and cylindrical threaded profiled pin tool, is being dealt with. Workpiece was chosen to be H13 tool steel with a diameter of 22[Formula: see text]mm and 110[Formula: see text]mm length. Turning and threading was done on CNC machine tools using CNMG 12404-THM uncoated tungsten carbide cutting tool. For residual stress measurement of the workpieces, an XRD-based Pulsetec[Formula: see text]-X360n portable residual stress analyzer setup was used. The experimental results show that the cylindrical pin profile tool had a compressive residual stress of [Formula: see text][Formula: see text]MPa and compressive residual shear stress of [Formula: see text][Formula: see text]MPa, while the cylindrical threaded pin profile tool had a compressive residual stress of [Formula: see text][Formula: see text]MPa (51.8% more) and compressive residual shear stress of [Formula: see text][Formula: see text]MPa (40% less). It has been concluded that due to threading operation on the cylindrical threaded pin profile, the value of residual stress is more in it, and since the stress is compressive in nature, it would have a better positive impact while doing FSP/FSW than that of the cylindrical profiled pin tool.

The Qualitative Research of Macro-Micro Association of Sand under the Monotonic Loading

2011 ◽  
Vol 261-263 ◽  
pp. 1544-1548 ◽  
Author(s):  
Wen Bai Liu ◽  
Ye Xun Li ◽  
Liang Cao
Keyword(s):  
Qualitative Research ◽  
Shear Stress ◽  
Water Content ◽  
Void Ratio ◽  
Particle Number ◽  
Sand Particle ◽  
Short Axis ◽  
Particle Mechanics ◽  
Projection Length ◽  
Association Table

By analyzing the association relationships between sand particle mechanics parameters and microscopic characteristics, this paper qualitative establishes the association table including physical and mechanical parameters such as the water content w, void ratio e and shear stress, and micro-parameters of sand particle such as particle number n, long axis L, short axis B, x, y coordinate of the centroid of particle, y-axis projection length, degree of eccentricity and orientation arrangement. Then the macro-micro relationship table of sand was established. The macro-micro relationship table of sand indicated that three micro-parameters of sand particle including particle number n, long axis L, short axis B have closely relationship with the water content w, void ratio e and shear stress. And the qualitative research between the sand particle mechanics and microscopic characteristics laid the foundation for the macro-micro association research.

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