scholarly journals Plane strain shear strength of unsaturated fiber-reinforced fine-grained soils

2021 ◽  
Author(s):  
Houman Soleimani-Fard ◽  
Diethard König ◽  
Meisam Goudarzy
Keyword(s):  
Mechanical Properties ◽  
Shear Strength ◽  
Hydraulic Conductivity ◽  
Soil Conditions ◽  
Shear Strength Parameters ◽  
Strength Parameters ◽  
Fine Grained ◽  
Vapor Equilibrium ◽  
Wide Range ◽  
Ductile Behavior

AbstractDiscrete randomly distributed fibers are commonly used to improve the engineering characteristics of the soil and thus soil properties such as shear strength, compressibility, density, and hydraulic conductivity. Most studies have so far focused on describing the behavior of soils containing randomly distributed fibers under dried or saturated conditions. However, the water table may seasonally fluctuate, thus generating unsaturated soil conditions. Therefore, a better understanding of the hydro-mechanical properties of unsaturated improved soils is of high necessity. In this research, the shear strength parameters of fine-grained soils were evaluated using the biaxial device available at Ruhr Universität Bochum. The applied device was modified to test unsaturated fine-grained soils with various degrees of saturation using axis translation and vapor equilibrium techniques. The experiments were conducted on fine soils containing 0, 0.5, and 1% fiber contents under a wide range of matric suctions. The ductile behavior was more noticeable in samples with lower suctions and higher straw contents. Furthermore, the shear strength of both unreinforced and reinforced fine-grained soils considerably increased by an increase in the suction. Finally, shear band inclination increased by the suction while decreasing by straw content.

scholarly journals Stability analysis of construction and demolition waste (CDW) deposits in theabandoned quarry of Profitis Ilias, Kozani, Greece.

2013 ◽  
Vol 47 (4) ◽  
pp. 1706
Author(s):  
G. Konstantopoulou ◽  
N. Spanou
Keyword(s):  
Shear Strength ◽  
Stability Analysis ◽  
Back Analysis ◽  
Field Tests ◽  
Construction And Demolition Waste ◽  
Shear Strength Parameters ◽  
Strength Parameters ◽  
Demolition Waste ◽  
Waste Dumps ◽  
Wide Range

Abandoned quarries become favourable sites for uncontrolled waste dumps, causing major safety hazards because of potential mass movements. An old quarry, near the town of Kozani, is filled with 772.000 m3 Construction and Demolition Wastes (CDW), containing a variety of materials (aggregates, wood, metals, plastics, bricks, soil etc.), in a wide range of fragment sizes, from clay to boulders. The size of particles and voids influence the behaviour of the filled slope, affecting both shear strength and drainage characteristics. Major factors that should be considered in a stability analysis for CDW, include waste material and soil cover composition, overall degree of compaction, moisture contented, permeability, pore pressure and shear strength parameters. Shear strength parameters were chosen by bibliographic references based on specialized field tests of similar materials. The analyzed profiles computed slip zones of low thickness and range. Therefore, successive back analysis was conducted to the sites of mapped cracks, aimed to determinate the mechanical properties of the slope during the failure. Since, friction angle and bulk density were retained for back analysis, the cohesion was examined. Although deposits are composed of loose heterogeneous materials, which have not been condensed, cohesion exists owing to the "interlocking" of the varying particle size of materials.

scholarly journals Effect of temperature on the residual shear strength of fine grained soil

2021 ◽  
Author(s):  
Marcin Witowski ◽  
Witold Bogusz
Keyword(s):  
Shear Strength ◽  
Natural Variability ◽  
Heat Extraction ◽  
Effect Of Temperature ◽  
Shear Strength Parameters ◽  
Strength Parameters ◽  
Residual Shear Strength ◽  
Temperature Changes ◽  
Fine Grained ◽  
The Impact

Abstract The impact of low-range temperature variation on the residual shear strength parameters has been investigated. For this purpose, a standard ring shear apparatus has been subjected to low-cost modifications and equipped with thermoelectric temperature control system constructed in-house. This allowed to conduct a series of tests for clay samples at temperatures of 5°C and 20°C, which is a typical range of variation for thermo-active structures during heat extraction. In order to distinguish the impact of temperature from the natural variability of the soil samples, additional temperature changes during shearing were performed, after residual strength had been reached. The obtained results revealed an observable impact of the temperature change on the residual shear strength of tested clay; however, the variance has been close to the resolution of the measurement sensor and within the range comparable to the natural variability of fine-grained soils. Therefore, low-range temperature changes can be considered as negligible in regard to the residual shear strength parameters.

scholarly journals Statistical evaluation of shear strength parameters of fine grained tills

2021 ◽  
Author(s):  
Chandra Prakash Poudyal
Keyword(s):  
Shear Strength ◽  
Stress Ratio ◽  
Maximum Stress ◽  
Shear Failure ◽  
Triaxial Tests ◽  
Ratio Method ◽  
Shear Strength Parameters ◽  
Strength Parameters ◽  
Fine Grained ◽  
Deviator Stress

A statistical analysis is conducted in this study on the shear strength parameters of fine-grained tills from a series of consolidated undrained triaxial tests performed for a light rail transit project in the City of Toronto. Three different failure criteria are applied: the maximum stress ratio, the maximum deviator stress, and the residual stress. Three methods generate only minimal difference in the shear failure angle and a slight difference in cohesion. The friction angle calculated using the maximum stress ratio method ranges from 18.6 to 35.26 degrees compared with values ranging from 18.5 to 34.26 degrees by the maximum deviator stress method. The undrained shear modulus calculated from one-third and two-third peak deviator stress points generate a wide variation from 2 MPa to 167 MPa with an average value of 34 MPa.

scholarly journals Impact of shear strength parameters on slope stability

2020 ◽  
Vol 310 ◽  
pp. 00040
Author(s):  
Slávka Harabinová ◽  
Eva Panulinová
Keyword(s):  
Shear Strength ◽  
Internal Friction ◽  
Slope Stability ◽  
Factor Of Safety ◽  
Slip Surface ◽  
Friction Angle ◽  
Internal Friction Angle ◽  
Shear Strength Parameters ◽  
Strength Parameters ◽  
Fine Grained

Analysis and assessment of the slopes stability are an important in geotechnical engineering for all the times. The paper deals with the assessment of slope stability in fine-grained soils. The influence of change in shear strength parameters on the factor of safety has been studied. The factor of safety can be correctly obtained only if the critical failure surface of the slope is accurately identified and shear strength parameters are correctly. To investigate effect of soil strength parameters on the factor of safety, different values of shear strength parameters: cohesion (c), internal friction angle (ϕ), were chosen. The calculation and assessment of slope stability was made using methods which assume a circular shape of the slip surface (Bishop and Petterson method) and methods that consider the polygonal shape of the slip surface (Spencer and Janbu method). We analyzed the impact of shear strength parameters of the resulting factor of slope stability of fine grained soil. The results of the study showed that the factor of safety of the slope changes with varying cohesion c and internal friction angle ϕ.

A torsional shear box for determining the shear strength of agricultural soils

Soil Research ◽  
1982 ◽  
Vol 20 (3) ◽  
pp. 203 ◽  
Author(s):  
JE Lloyd ◽  
N Collis-George
Keyword(s):  
Shear Strength ◽  
Agricultural Soils ◽  
Field Studies ◽  
Soil Strength ◽  
Field Conditions ◽  
Soil Conditions ◽  
Strength Parameters ◽  
Torsional Shear ◽  
Wide Range ◽  
Shear Box

A hand-held torsional shear box, suitable for direct measurements of the in situ soil strength (�o) under field conditions and for laboratory determinations of shear strength parameters, is described. A field procedure is given, and the errors in the method are discussed. Under field conditions, it is simple to operate and requires a single measurement to determine �o. Field studies indicate that it is suitable for a wide range of soil conditions which occur in agricultural soils. Results are presented, which show that both moisture status and structure influence the value of �o, as well as the nature of the failure plane. Agricultural soils have a number of characteristics which make it difficult to design methods for determining soil strength parameters or to interpret empirical estimates of soil strength. Chief amongst these are: (1) marked changes in most soil physical properties with depth; (2) a polymodal distribution of pore sizes. Because the measurement is on a surface which is nearly horizontal and is of an area to allow for all forms of failure, the described torsional shear box largely overcomes these problems, and provides a value of �o which is physically interpretable and relevant to studies concerned with soil failure.

scholarly journals Studi Pendahuluan Sifat Teknis Tanah Lempung Pada Daerah Rawan Gerakan Tanah Di Dusun Beji Desa Cirahab Kecamatan Lumbir Kabupaten Banyumas

2021 ◽  
Vol 22 (1) ◽  
pp. 35
Author(s):  
Ary Sismiani ◽  
Iwan Rustendi
Keyword(s):  
Mechanical Properties ◽  
Shear Strength ◽  
Moisture Content ◽  
Water Content ◽  
Strength Parameter ◽  
Soil Slope ◽  
Shear Strength Parameters ◽  
Strength Parameters ◽  
Soil Movement ◽  
Soil Shear Strength

In several places in the Banyumas Regency area, land movement problems have often occurred. Several locations have been declared as red zones, one of which is Beji, Cirahab Village, Lumbir District. With such regional conditions, it is necessary to conduct a study of the technical and mechanical properties of the soil in that location including moisture content, density and shear strength parameters related to the possibility of soil movement that will occur. From the results of the test and analysis using 3 specimens, the following data were obtained: water content of 20.22%, 30.36%, 40.31% with a cohesion value of 0.14 kg / cm2, 0.56 kg / cm2, 0.33 kg / cm2, and the internal friction angles of the soil are 30.22 °, 24.47 °, and 18.93 °. While the value of shear stress and displacement at maximum normal stress and moisture content of 20.22%, 30.36%, 40.31% are t(w1) = 0.68 kg / cm2,  t(w2) = 1.01 kg / cm2 ,t (w3) = 0.68 kg / cm2 and dn1 = 15.02%, dn2 = 10.02, dn3 = 13.35%. It can be concluded that the water content always has a very big influence on the value of the soil shear strength parameter. Therefore, the condition of the water content on the soil slope needs to be considered, and it is necessary to carry out further tests and more serious handling at that location.

scholarly journals Statistical evaluation of shear strength parameters of fine grained tills

2021 ◽  
Author(s):  
Chandra Prakash Poudyal
Keyword(s):  
Shear Strength ◽  
Stress Ratio ◽  
Maximum Stress ◽  
Shear Failure ◽  
Triaxial Tests ◽  
Ratio Method ◽  
Shear Strength Parameters ◽  
Strength Parameters ◽  
Fine Grained ◽  
Deviator Stress

A statistical analysis is conducted in this study on the shear strength parameters of fine-grained tills from a series of consolidated undrained triaxial tests performed for a light rail transit project in the City of Toronto. Three different failure criteria are applied: the maximum stress ratio, the maximum deviator stress, and the residual stress. Three methods generate only minimal difference in the shear failure angle and a slight difference in cohesion. The friction angle calculated using the maximum stress ratio method ranges from 18.6 to 35.26 degrees compared with values ranging from 18.5 to 34.26 degrees by the maximum deviator stress method. The undrained shear modulus calculated from one-third and two-third peak deviator stress points generate a wide variation from 2 MPa to 167 MPa with an average value of 34 MPa.

Sign in / Sign up

Export Citation Format

Share Document