**Commenced**in January 2007

**Frequency:**Monthly

**Edition:**International

**Paper Count:**1413

# Search results for: Shear stress

##### 1413 Effect of Silt Presence on Shear Strength Parameters of Unsaturated Sandy Soils

**Authors:**
R. Ziaie Moayed,
E. Khavaninzadeh,
M. Ghorbani Tochaee

**Abstract:**

Direct shear test is widely used in soil mechanics experiment to determine the shear strength parameters of granular soils. For analysis of soil stability problems such as bearing capacity, slope stability and lateral pressure on soil retaining structures, the shear strength parameters must be known well. In the present study, shear strength parameters are determined in silty-sand mixtures. Direct shear tests are performed on 161 Firoozkooh sand with different silt content at a relative density of 70% in three vertical stress of 100, 150, and 200 kPa. Wet tamping method is used for soil sample preparation, and the results include diagrams of shear stress versus shear deformation and sample height changes against shear deformation. Accordingly, in different silt percent, the shear strength parameters of the soil such as internal friction angle and dilation angle are calculated and compared. According to the results, when the sample contains up to 10% silt, peak shear strength and internal friction angle have an upward trend. However, if the sample contains 10% to 50% of silt a downward trend is seen in peak shear strength and internal friction angle.

**Keywords:**
Shear strength parameters,
direct shear test,
silty sand,
shear stress,
shear deformation.

##### 1412 Modified Hybrid Genetic Algorithm-Based Artificial Neural Network Application on Wall Shear Stress Prediction

**Authors:**
Zohreh Sheikh Khozani,
Wan Hanna Melini Wan Mohtar,
Mojtaba Porhemmat

**Abstract:**

Prediction of wall shear stress in a rectangular channel, with non-homogeneous roughness distribution, was studied. Estimation of shear stress is an important subject in hydraulic engineering, since it affects the flow structure directly. In this study, the Genetic Algorithm Artificial (GAA) neural network is introduced as a hybrid methodology of the Artificial Neural Network (ANN) and modified Genetic Algorithm (GA) combination. This GAA method was employed to predict the wall shear stress. Various input combinations and transfer functions were considered to find the most appropriate GAA model. The results show that the proposed GAA method could predict the wall shear stress of open channels with high accuracy, by Root Mean Square Error (RMSE) of 0.064 in the test dataset. Thus, using GAA provides an accurate and practical simple-to-use equation.

**Keywords:**
Artificial neural network,
genetic algorithm,
genetic programming,
rectangular channel,
shear stress.

##### 1411 Exact Solution of Some Helical Flows of Newtonian Fluids

**Authors:**
Imran Siddique

**Abstract:**

**Keywords:**
Newtonian fluids,
Velocity field,
Exact solutions,
Shear stress,
Cylindrical domains.

##### 1410 Flow Properties of Wood Pulp Suspensions in Pipes

**Authors:**
M. Sumida

**Abstract:**

The flow of suspensions of wood pulp fibers in circular pipes has been investigated experimentally. The flow characteristics of pulp suspensions are discussed with regard to five flow regimes designated by the author. In particular, the effects of the shear stress at the pipe wall on the disruption and dispersion of networks of pulp fibers are examined. The values of the disruptive and dispersive shear stresses are formulated as simple expressions depending on only the fiber concentration. Furthermore, the flow properties of the suspensions are described using the yield shear stress.

**Keywords:**
Fiber Concentration,
Flow Properties,
Pulp Suspension,
Yield Shear Stress.

##### 1409 Free Vibration and Buckling of Rectangular Plates under Nonuniform In-Plane Edge Shear Loads

**Authors:**
T. H. Young,
Y. J. Tsai

**Abstract:**

A method for determining the stress distribution of a rectangular plate subjected to two pairs of arbitrarily distributed in-plane edge shear loads is proposed, and the free vibration and buckling of such a rectangular plate are investigated in this work. The method utilizes two stress functions to synthesize the stress-resultant field of the plate with each of the stress functions satisfying the biharmonic compatibility equation. The sum of stress-resultant fields due to these two stress functions satisfies the boundary conditions at the edges of the plate, from which these two stress functions are determined. Then, the free vibration and buckling of the rectangular plate are investigated by the Galerkin method. Numerical results obtained by this work are compared with those appeared in the literature, and good agreements are observed.

**Keywords:**
Stress analysis,
free vibration,
plate buckling,
nonuniform in-plane edge shear.

##### 1408 Numerical Solution for Elliptical Crack with Developing Cusps Subject to Shear Loading

**Authors:**
Nik Mohd Asri Nik Long,
Koo Lee Feng,
Zainidin K. Eshkuvatov,
A. A. Khaldjigitov

**Abstract:**

This paper study the behavior of the solution at the crack edges for an elliptical crack with developing cusps, Ω in the plane elasticity subjected to shear loading. The problem of finding the resulting shear stress can be formulated as a hypersingular integral equation over Ω and it is then transformed into a similar equation over a circular region, D, using conformal mapping. An appropriate collocation points are chosen on the region D to reduce the hypersingular integral equation into a system of linear equations with (2N+1)(N+1) unknown coefficients, which will later be used in the determination of shear stress intensity factors and maximum shear stress intensity. Numerical solution for the considered problem are compared with the existing asymptotic solution, and displayed graphically. Our results give a very good agreement to the existing asymptotic solutions.

**Keywords:**
Elliptical crack,
stress intensity factors,
hyper singular integral equation,
shear loading,
conformal mapping.

##### 1407 Flexure of Cantilever Thick Beams Using Trigonometric Shear Deformation Theory

**Authors:**
Yuwaraj M. Ghugal,
Ajay G. Dahake

**Abstract:**

A trigonometric shear deformation theory for flexure of thick beams, taking into account transverse shear deformation effects, is developed. The number of variables in the present theory is same as that in the first order shear deformation theory. The sinusoidal function is used in displacement field in terms of thickness coordinate to represent the shear deformation effects. The noteworthy feature of this theory is that the transverse shear stresses can be obtained directly from the use of constitutive relations with excellent accuracy, satisfying the shear stress free conditions on the top and bottom surfaces of the beam. Hence, the theory obviates the need of shear correction factor. Governing differential equations and boundary conditions are obtained by using the principle of virtual work. The thick cantilever isotropic beams are considered for the numerical studies to demonstrate the efficiency of the. Results obtained are discussed critically with those of other theories.

**Keywords:**
Trigonometric shear deformation,
thick beam,
flexure,
principle of virtual work,
equilibrium equations,
stress.

##### 1406 Influence of Composite Adherents Properties on the Dynamic Behavior of Double Lap Bonded Joint

**Authors:**
P. Saleh,
G. Challita,
R. Hazimeh,
K. Khalil

**Abstract:**

In this paper 3D FEM analysis was carried out on double lap bonded joint with composite adherents subjected to dynamic shear. The adherents are made of Carbon/Epoxy while the adhesive is epoxy Araldite 2031. The maximum average shear stress and the stress homogeneity in the adhesive layer were examined. Three fibers textures were considered: UD; 2.5D and 3D with same volume fiber then a parametric study based on changing the thickness and the type of fibers texture in 2.5D was accomplished. Moreover, adherents’ dissimilarity was also investigated. It was found that the main parameter influencing the behavior is the longitudinal stiffness of the adherents. An increase in the adherents’ longitudinal stiffness induces an increase in the maximum average shear stress in the adhesive layer and an improvement in the shear stress homogeneity within the joint. No remarkable improvement was observed for dissimilar adherents.

**Keywords:**
Adhesive,
Composite adherents,
Impact shear,
Finite
element.

##### 1405 Numerical Modeling of Direct Shear Tests on Sandy Clay

**Authors:**
R. Ziaie Moayed ,
S. Tamassoki ,
E. Izadi

**Abstract:**

**Keywords:**
Shear strength,
Finite element analysis,
Large direct
shear test,
Sandy clay.

##### 1404 Flexure of Simply Supported Thick Beams Using Refined Shear Deformation Theory

**Authors:**
Yuwaraj M. Ghugal,
Ajay G. Dahake

**Abstract:**

A trigonometric shear deformation theory for flexure of thick beams, taking into account transverse shear deformation effects, is developed. The number of variables in the present theory is same as that in the first order shear deformation theory. The sinusoidal function is used in displacement field in terms of thickness coordinate to represent the shear deformation effects. The noteworthy feature of this theory is that the transverse shear stresses can be obtained directly from the use of constitutive relations with excellent accuracy, satisfying the shear stress free conditions on the top and bottom surfaces of the beam. Hence, the theory obviates the need of shear correction factor. Governing differential equations and boundary conditions are obtained by using the principle of virtual work. The thick simply supported isotropic beams are considered for the numerical studies to demonstrate the efficiency of the results obtained is discussed critically with those of other theories.

**Keywords:**
Trigonometric shear deformation,
thick beam,
flexure,
principle of virtual work,
equilibrium equations,
stress.

##### 1403 A Study of Shear Stress Intensity Factor of PP and HDPE by a Modified Experimental Method together with FEM

**Authors:**
Md. Shafiqul Islam,
Abdullah Khan,
Sharon Kao-Walter,
Li Jian

**Abstract:**

Shear testing is one of the most complex testing areas where available methods and specimen geometries are different from each other. Therefore, a modified shear test specimen (MSTS) combining the simple uniaxial test with a zone of interest (ZOI) is tested which gives almost the pure shear. In this study, material parameters of polypropylene (PP) and high density polyethylene (HDPE) are first measured by tensile tests with a dogbone shaped specimen. These parameters are then used as an input for the finite element analysis. Secondly, a specially designed specimen (MSTS) is used to perform the shear stress tests in a tensile testing machine to get the results in terms of forces and extension, crack initiation etc. Scanning Electron Microscopy (SEM) is also performed on the shear fracture surface to find material behavior. These experiments are then simulated by finite element method and compared with the experimental results in order to confirm the simulation model. Shear stress state is inspected to find the usability of the proposed shear specimen. Finally, a geometry correction factor can be established for these two materials in this specific loading and geometry with notch using Linear Elastic Fracture Mechanics (LEFM). By these results, strain energy of shear failure and stress intensity factor (SIF) of shear of these two polymers are discussed in the special application of the screw cap opening of the medical or food packages with a temper evidence safety solution.

**Keywords:**
Shear test specimen,
Stress intensity factor,
Finite Element simulation,
Scanning electron microscopy,
Screw cap opening.

##### 1402 Buckling Analysis of Rectangular Plates under the Combined Action of Shear and Uniaxial Stresses

**Authors:**
V. Piscopo

**Abstract:**

**Keywords:**
Buckling analysis,
Shear,
Uniaxial Stresses.

##### 1401 Study the Effect of Roughness on the Higher Order Moment to Extract Information about the Turbulent Flow Structure in an Open Channel Flow

**Authors:**
Md Abdullah Al Faruque,
Ram Balachandar

**Abstract:**

The present study was carried out to understand the extent of effect of roughness and Reynolds number in open channel flow (OCF). To this extent, four different types of bed surface conditions consisting smooth, distributed roughness, continuous roughness, natural sand bed and two different Reynolds number for each bed surfaces were adopted in this study. Particular attention was given on mean velocity, turbulence intensity, Reynolds shear stress, correlation, higher order moments and quadrant analysis. Further, the extent of influence of roughness and Reynolds number in the depth-wise direction also studied. Increasing Reynolds shear stress near rough beds are noticed due to arrays of discrete roughness elements and flow over these elements generating a series of wakes which contributes to the generation of significantly higher Reynolds shear stress.

**Keywords:**
Bed roughness,
ejection,
sweep,
open channel flow,
Reynolds Shear Stress,
turbulent boundary layer,
velocity triple product.

##### 1400 Effects of Slip Condition and Peripheral Layer on Couple Stress Fluid Flow through a Channel with Mild Stenosis

**Authors:**
Gurju Awgichew,
G. Radhakrishnamacharya

**Abstract:**

Steady incompressible couple stress fluid flow through two dimensional symmetric channel with stenosis is investigated. The flow consisting of a core region to be a couple stress fluid and a peripheral layer of plasma (Newtonian fluid). Assuming the stenosis to be mild, the equations governing the flow of the proposed model are solved using the slip boundary condition and closed form expressions for the flow characteristics (the dimensionless resistance to flow and wall shear stress at the maximum height of stenosis) are derived. The effects of various parameters on these flow variables have been studied. It is observed that the resistance to flow as well as the wall shear stress increase with the height of stenosis, viscosity ratio and Darcy number. However, the trend is reversed as the slip and the couple stress parameter increase.

**Keywords:**
Stenosis,
Couple stress fluid,
Slip condition,
Peripheral layer.

##### 1399 An Improved Heat Transfer Prediction Model for Film Condensation inside a Tube with Interphacial Shear Effect

**Authors:**
V. G. Rifert,
V. V. Gorin,
V. V. Sereda,
V. V. Treputnev

**Abstract:**

The analysis of heat transfer design methods in condensing inside plain tubes under existing influence of shear stress is presented in this paper. The existing discrepancy in more than 30-50% between rating heat transfer coefficients and experimental data has been noted. The analysis of existing theoretical and semi-empirical methods of heat transfer prediction is given. The influence of a precise definition concerning boundaries of phase flow (it is especially important in condensing inside horizontal tubes), shear stress (friction coefficient) and heat flux on design of heat transfer is shown. The substantiation of boundary conditions of the values of parameters, influencing accuracy of rated relationships, is given. More correct relationships for heat transfer prediction, which showed good convergence with experiments made by different authors, are substantiated in this work.

**Keywords:**
Film condensation,
heat transfer,
plain tube,
shear stress.

##### 1398 Rheological Behavior of Fresh Activated Sludge

**Authors:**
Salam K. Al-Dawery

**Abstract:**

Despite of few research works on municipal sludge, still there is a lack of actual data. Thus, this work was focused on the conditioning and rheology of fresh activated sludge. The effect of cationic polyelectrolyte has been investigated at different concentrations and pH values in a comparative fashion. Yield stress is presented in all results indicating the minimum stress that necessary to reach flow conditions. Connections between particle-particle is the reason for this yield stress, also, the addition of polyelectrolyte causes strong bonds between particles and water resulting in the aggregation of particles which required higher shear stress in order to flow. The results from the experiments indicate that the cationic polyelectrolytes have significant effluence on the sludge characteristic and water quality such as turbidity, SVI, zone settling rate and shear stress.

**Keywords:**
Rheology,
Polyelectrolyte,
Settling volume index,
Turbidity.

##### 1397 Experimental Investigation on the Shear Strength Parameters of Sand-Slag Mixtures

**Authors:**
Ayad Salih Sabbar,
Amin Chegenizadeh,
Hamid Nikraz

**Abstract:**

Utilizing waste materials in civil engineering applications has a positive influence on the environment by reducing carbon dioxide emissions and issues associated with waste disposal. Granulated blast furnace slag (GBFS) is a by-product of the iron and steel industry, with millions of tons of slag being annually produced worldwide. Slag has been widely used in structural engineering and for stabilizing clay soils; however, studies on the effect of slag on sandy soils are scarce. This article investigates the effect of slag content on shear strength parameters through direct shear tests and unconsolidated undrained triaxial tests on mixtures of Perth sand and slag. For this purpose, sand-slag mixtures, with slag contents of 2%, 4%, and 6% by weight of samples, were tested with direct shear tests under three normal stress values, namely 100 kPa, 150 kPa, and 200 kPa. Unconsolidated undrained triaxial tests were performed under a single confining pressure of 100 kPa and relative density of 80%. The internal friction angles and shear stresses of the mixtures were determined via the direct shear tests, demonstrating that shear stresses increased with increasing normal stress and the internal friction angles and cohesion increased with increasing slag. There were no significant differences in shear stresses parameters when slag content rose from 4% to 6%. The unconsolidated undrained triaxial tests demonstrated that shear strength increased with increasing slag content.

**Keywords:**
Direct shear,
shear strength,
slag,
UU test.

##### 1396 Hemodynamic Characteristics in the Human Carotid Artery Model Induced by Blood-Arterial Wall Interactions

**Authors:**
Taewon Seo

**Abstract:**

The characteristics of physiological blood flow in human carotid arterial bifurcation model have been numerically studied using a fully coupled fluid-structure interaction (FSI) analysis. This computational model with the fluid-structure interaction is constructed to investigate the flow characteristics and wall shear stress in the carotid artery. As the flow begins to decelerate after the peak flow, a large recirculation zone develops at the non-divider wall of both internal carotid artery (ICA) and external carotid artery (ECA) in FSI model due to the elastic energy stored in the expanding compliant wall. The calculated difference in wall shear stress (WSS) in both Non-FSI and FSI models is a range of between 5 and 11% at the mean WSS. The low WSS corresponds to regions of carotid artery that are more susceptible to atherosclerosis.

**Keywords:**
Carotid artery,
Fluid-structure interaction,
Hemodynamics,
Wall shear stress.

##### 1395 Numerical Simulation of Punching Shear of Flat Plates with Low Reinforcement

**Authors:**
Fatema-Tuz-Zahura,
Raquib Ahsan

**Abstract:**

**Keywords:**
Flat plate,
finite element model,
punching shear,
reinforcement ratio.

##### 1394 Experimental Study of Light Crude Oil-Water Emulsions

**Authors:**
M. Meriem-Benziane,
Sabah A. Abdul-Wahab,
H. Zahloul,
M. Belhadri

**Abstract:**

This paper made an attempt to investigate the problem associated with enhancement of emulsions of light crude oil-water recovery in an oil field of Algerian Sahara. Measurements were taken through experiments using RheoStress (RS600). Factors such as shear rate, temperature and light oil concentration on the viscosity behavior were considered. Experimental measurements were performed in terms of shear stress–shear rate, yield stress and flow index on mixture of light crude oil–water. The rheological behavior of emulsion showed Non-Newtonian shear thinning behavior (Herschel-Bulkley). The experiments done in the laboratory showed the stability of some water in light crude oil emulsions form during consolidate oil recovery process. To break the emulsion using additives may involve higher cost and could be very expensive. Therefore, further research should be directed to find solution of these problems that have been encountered.

**Keywords:**
Emulsion,
Flow index,
Herschel-Bulkley model,
Newton model,
Oil field,
Rheology,
Yield stress

##### 1393 An Experimental Investigation in Effect of Confining Stress and Matric Suction on the Mechanical Behavior of Sand with Different Fine Content

**Authors:**
S. Asreazad

**Abstract:**

This paper presents the results that the soil volumetric strain and shear strength are closely related to the confining stress and initial matric suction under constant water content testing on the specimens of unsaturated sand with clay and silt fines contents. The silty sand specimens reached their peak strength after a very small axial strain followed by a post-peak softening towards an ultimate value. The post-peak drop in stress increased by an increment of the suction, while there is no peak strength for clayey sand specimens. The clayey sand shows compressibility and possesses ductile stress-strain behaviour. Shear strength increased nonlinearly with respect to matric suction for both soil types. When suction exceeds a certain range, the effect of suction on shear strength increment weakens gradually. Under the same confining stress, the dilatant tendencies in the silty sand increased under lower values of suction and decreased for higher suction values under the same confining stress. However, the amount of contraction increased with increasing initial suction for clayey sand specimens.

**Keywords:**
Unsaturated soils,
silty sand,
clayey sand,
triaxial test,
constant water content.

##### 1392 Shear Modulus Degradation of a Liquefiable Sand Deposit by Shaking Table Tests

**Authors:**
Henry Munoz,
Muhammad Mohsan,
Takashi Kiyota

**Abstract:**

Strength and deformability characteristics of a liquefiable sand deposit including the development of earthquake-induced shear stress and shear strain as well as soil softening via the progressive degradation of shear modulus were studied via shaking table experiments. To do so, a model of a liquefiable sand deposit was constructed and densely instrumented where accelerations, pressures, and displacements at different locations were continuously monitored. Furthermore, the confinement effects on the strength and deformation characteristics of the liquefiable sand deposit due to an external surcharge by placing a heavy concrete slab (i.e. the model of an actual structural rigid pavement) on the ground surface were examined. The results indicate that as the number of seismic-loading cycles increases, the sand deposit softens progressively as large shear strains take place in different sand elements. Liquefaction state is reached after the combined effects of the progressive degradation of the initial shear modulus associated with the continuous decrease in the mean principal stress, and the buildup of the excess of pore pressure takes place in the sand deposit. Finally, the confinement effects given by a concrete slab placed on the surface of the sand deposit resulted in a favorable increasing in the initial shear modulus, an increase in the mean principal stress and a decrease in the softening rate (i.e. the decreasing rate in shear modulus) of the sand, thus making the onset of liquefaction to take place at a later stage. This is, only after the sand deposit having a concrete slab experienced a higher number of seismic loading cycles liquefaction took place, in contrast to an ordinary sand deposit having no concrete slab.

**Keywords:**
Liquefaction,
shaking table,
shear modulus degradation,
earthquake.

##### 1391 Application Research on Large Profiled Statues of Steel-Concrete Composite Shear Wall

**Authors:**
Zhao Cai-qi,
Ma Jun

**Abstract:**

**Keywords:**
Twin steel plates-concrete composite shear wall,
huge statue of Buddha,
shear capacity,
initial lateral stiffness,
overturning moment bearing.

##### 1390 Flow of a Second Order Fluid through Constricted Tube with Slip Velocity at Wall Using Integral Method

**Authors:**
Nosheen Zareen Khan,
Abdul Majeed Siddiqui,
Muhammad Afzal Rana

**Abstract:**

**Keywords:**
Approximate solution,
constricted tube,
non-Newtonian fluids,
Reynolds number.

##### 1389 Experimental Study of Strength Recovery from Residual Strength on Kaolin Clay

**Authors:**
Deepak R. Bhat,
Netra P. Bhandery,
Ryuichi Yatabe

**Abstract:**

Strength recovery effect from the residual-state of shear is not well address in scientific literature. Torsional ring shear strength recovery tests on kaolin clay using rest periods up to 30 days are performed at the effective normal stress 100kN/m2. Test results shows that recovered strength measured in the laboratory is slightly noticeable after rest period of 3 days, but recovered strength lost after very small shear displacement. This paper mainly focused on the strength recovery phenomenon from the residual strength of kaolin clay based on torsional ring shear test results. Mechanisms of recovered strength are also discussed.

**Keywords:**
Kaolin clay,
Residual strength,
Strength recovery,
Torsional ring shear test.

##### 1388 Development of a New Method for T-joint Specimens Testing under Shear Loading

**Authors:**
R. Doubrava,
R. Růžek

**Abstract:**

Nonstandard tests are necessary for analyses and verification of new developed structural and technological solutions with application of composite materials. One of the most critical primary structural parts of a typical aerospace structure is T-joint. This structural element is loaded mainly in shear, bending, peel and tension. The paper is focused on the shear loading simulations. The aim of the work is to obtain a representative uniform distribution of shear loads along T-joint during the mechanical testing. A new design of T-joint test procedure, numerical simulation and optimization of representative boundary conditions are presented. The different conditions and inaccuracies both in simulations and experiments are discussed. The influence of different parameters on stress and strain distributions is demonstrated on T-joint made of CFRP (carbon fibre reinforced plastic). A special test rig designed by VZLU (Aerospace Research and Test Establishment) for T-shear test procedure is presented.

**Keywords:**
T-joint,
shear,
composite,
mechanical testing,
Finite
Element analysis,
methodology.

##### 1387 Pulsating Flow of an Incompressible Couple Stress Fluid Between Permeable Beds

**Authors:**
T. K. V. Iyengar,
Punnamchandar Bitla

**Abstract:**

The paper deals with the pulsating flow of an incompressible couple stress fluid between permeable beds. The couple stress fluid is injected into the channel from the lower permeable bed with a certain velocity and is sucked into the upper permeable bed with the same velocity. The flow between the permeable beds is assumed to be governed by couple stress fluid flow equations of V. K. Stokes and that in the permeable regions by Darcy-s law. The equations are solved analytically and the expressions for velocity and volume flux are obtained. The effects of the material parameters are studied numerically and the results are presented through graphs.

**Keywords:**
Pulsating flow,
couple stress fluid,
permeable beds,
mass flux,
shear stress.

##### 1386 Influence of Hydraulic Hysteresis on Effective Stress in Unsaturated Clay

**Authors:**
Anuchit Uchaipichat

**Abstract:**

**Keywords:**
Unsaturated soils,
Hydraulic hysteresis,
Effectivestress

##### 1385 Determination of Small Shear Modulus of Clayey Sand Using Bender Element Test

**Authors:**
R. Sadeghzadegan,
S. A. Naeini,
A. Mirzaii

**Abstract:**

In this article, the results of a series of carefully conducted laboratory test program were represented to determine the small strain shear modulus of sand mixed with a range of kaolinite including zero to 30%. This was experimentally achieved using a triaxial cell equipped with bender element. Results indicate that small shear modulus tends to increase, while clay content decreases and effective confining pressure increases. The exponent of stress in the power model regression analysis was not sensitive to the amount of clay content for all sand clay mixtures, while coefficient A was directly affected by change in clay content.

**Keywords:**
Small shear modulus,
bender element test,
plastic fines,
sand.

##### 1384 Analysis of Cyclic Elastic-Plastic Loading of Shaft Based On Kinematic Hardening Model

**Authors:**
Isa Ahmadi,
Ramin Khamedi

**Abstract:**

In this paper, the elasto-plastic and cyclic torsion of a shaft is studied using a finite element method. The Prager kinematic hardening theory of plasticity with the Ramberg and Osgood stress-strain equation is used to evaluate the cyclic loading behavior of the shaft under the torsional loading. The material of shaft is assumed to follow the non-linear strain hardening property based on the Prager model. The finite element method with C^{1} continuity is developed and used for solution of the governing equations of the problem. The successive substitution iterative method is used to calculate the distribution of stresses and plastic strains in the shaft due to cyclic loads. The shear stress, effective stress, residual stress and elastic and plastic shear strain distribution are presented in the numerical results.

**Keywords:**
Cyclic Loading,
Finite Element Analysis,
Prager Kinematic Hardening Model,
Torsion of shaft.