Sürdürülebilir Kalkınma Amaçları
Yayınlar
- MakaleYalnız künye2020Scopus SJRQ2Examination of analytical and finite element solutions regarding contact of a functionally graded layer
Yaylacı, Murat; Adıyaman, Gökhan; Öner, Erdal; Birinci, Ahmet
In this study, the continuous and discontinuous contact problems of functionally graded (FG) layer resting on a rigid foundation were considered. The top of the FG layer was loaded by a distributed load. It was assumed that the shear modulus and the density of the layer varied according to exponential functions along the depth whereas the the Poisson ratio remained constant. The problem first was solved analytically and the results were verified with the ones obtained from finite element (FE) solution. In analytical solution, the stress and displacement components for FG layer were obtained by the help of Fourier integral transform. Critical load expression and integral equation for continuous and discontinuous contact, respectively, using corresponding boundary conditions in each case. The finite element solution of the problem was carried out using ANSYS software program. In continuous contact case, initial separation distance and contact stresses along the contact surface between the FG layer and the rigid foundation were examined. Separation distances and contact stresses were obtained in case of discontinuous contact. The effect of material properties and loading were investigated using both analytical and FE solutions. It was shown that obtained results were compatible with each other.
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İncele - DüzeltmeAçık Erişim2020Scopus SJRQ2Correction to: Investigation of the solution for discontinuous contact problem between a functionally graded (FG) layer and homogeneous half-space (Archive of Applied Mechanics, (2020), 90, 12, (2799-2819), 10.1007/s00419-020-01750-y)
Öner, Erdal; Birinci, Ahmet
kUnfortunately, Figs. 5, 6, 8 and 10 have been processed incorrectly. Correct figures are provided in this correction article. The Original article has also been corrected.
AtıfScopus2WoS2OpenAlex2İncele - MakaleAçık Erişim2020Scopus SJRQ2Investigation of the solution for discontinuous contact problem between a functionally graded (FG) layer and homogeneous half-space
Öner, Erdal; Birinci, Ahmet
In this study, the discontinuous contact problem between a functionally graded (FG) layer, which is loaded symmetrically with point load P through a rigid block, and a homogeneous half-space was solved using the theory of elasticity and integral transform techniques. The shear modulus and density of the layer addressed in the problem vary with an exponential function along with its height. The half-space is homogeneous, and no binder exists on the contact surface containing the FG layer. In the solution, the body force of the FG layer was considered, whereas that of the homogeneous half-space was neglected. The Poisson’s ratios of both the FG layer and homogeneous half-space were assumed to remain constant. Additionally, all the surfaces addressed in the problem were assumed to be frictionless. Using the theory of elasticity and integral transform techniques, the discontinuous contact problem was reduced to two integral equations, wherein the contact stress under the rigid block and the slope of the separation, which occurred at the interface of the FG layer and homogeneous half-space, are unknown. These integral equations were solved numerically for the flat condition of the rigid block profile using the Gauss–Chebyshev integration formula. Consequently, the stress distributions, start–end points of the separation region, and separation displacements between the FG layer and homogeneous half-space were obtained for various dimensionless quantities.
AtıfScopus24WoS25OpenAlex23İncele - MakaleYalnız künye2018THE GENERAL SOLUTION OF A LAYERED MEDIUM RESTING ON A RIGID FOUNDATION
Adiyaman, Gokhan; Öner, Erdal; Birinci, Ahmet
In this study, the general solution of a receding contact problem of layered medium resting on rigid foundation is considered. The layered medium consists of N homogeneous layer with varying material properties and heights. The contact surfaces can be receding or attached. The problem may include M receding contact surfaces. The layered medium is loaded with n concentrated loads transmitted by circular stamps and r distributed loads. The problem is reduced to integral equation system using elasticity theory and Fourier integral transform. The numerical solution of the system is done by using Matlab. A program is written to solve the problem given by the user with any geometry and loading. The program is tested with two studies from the literature and it was shown that the results are compatible.
AtıfWoS3İncele - MakaleYalnız künye2017Mechanical Properties of Conventional Concrete Produced With Different Type of Aggregates in Bayburt Region
Tekin, Ilker; Kotan, Turkay; Yurdakul, Muhammet; Öner, Erdal
In this study, the limestone, natural aggregate, serpentine and Bayburt stone located in the province of Bayburt used as aggregate in conventional concrete production. In the experiments, the cement dosage and workability were kept constant. Slump, Ve-Be, unit weight and the highest temperature values in first 2 hours of the fresh concrete were measured. The concrete samples prepared with Bayburt stone were cured for 90 days and the others were cured for 28 days in lime-saturated water. Strain-stress data and water absorption values were measured on the hardened concretes at 7 and 28th days age through the records of stress and strain data during compressive strength tests. According to results of this study, the compressive strengths of the concrete samples with limestone, natural aggregate and serpentine were on average of 40, 35 and 5 MPa, respectively, on the 28th day. Also, in concrete samples with Bayburt stone, the compressive strengths were reached to 16 MPa for 28 days and to 22 MPa for 90 days.
AtıfWoS4OpenAlex3İncele - MakaleYalnız künye2017Scopus SJRQ1Continuous and discontinuous contact problem of a functionally graded layer resting on a rigid foundation
Adıyaman, Gökhan; Öner, Erdal; Birinci, Ahmet
In this study, the continuous and discontinuous contact problem of a functionally graded (FG) layer resting on a rigid foundation is considered. The top of the FG layer is subjected to normal tractions over a finite segment. The graded layer is modeled as a non-homogenous medium with a constant Poissons’ ratio and exponentially varying shear modules and density. For continuous contact, the problem was solved analytically using plane elasticity and integral transform techniques. The critical load that causes first separation and contact pressures is investigated for various material properties and loadings. The problem reduced to a singular integral equation using plane elasticity and integral transform techniques in case of discontinuous contact. The obtained singular integral equation is solved numerically using Gauss–Jacobi integral formulation, and an iterative scheme is employed to obtain the correct separation distance. The separation distance and contact pressures between the FG layer and the foundation are analyzed for various material properties and loading. The results are shown in Tables and Figures. It is seen that decreasing stiffness and density at the top of the layer result in an increment in both critical load in case of continuous contact and separation distance in case of discontinuous contact.
AtıfScopus24WoS24OpenAlex26İncele - MakaleYalnız künye2016ANALYSIS OF A LONG STRIP CONTAINING AN INTERNAL OR EDGE CRACK USING FEM
Yaylaci, Murat; Birinci, Ahmet; Adiyaman, Gokhan; Öner, Erdal
This paper presents the elastostatic plane problem of a long strip containing an internal or edge crack perpendicular to its boundaries. The plane problem consists of an infinitely long strip of thickness h. The infinitely long strip is loaded by uniformly distributed load and rests on two simple supports. It is assumed that the effect of gravity is neglected. The finite element model of the problem is constituted using ANSYS software and the two dimensional analysis of the problem is carried out. Normalized stress-intensity factors for the cases with internal and edge crack, and normal stress (sigma(x)) for uncracked layer case are obtained for various dimensionless quantities. Finally, the results obtained from the finite element analysis are verified by comparing with analytical ones and it is seen that the results from finite element analysis indicate a good agreement with the analytical solution.
AtıfWoS4İncele - MakaleYalnız künye2016Scopus SJRQ1A receding contact problem between a functionally graded layer and two homogeneous quarter planes
Adıyaman, Gökhan; Birinci, Ahmet; Öner, Erdal; Yaylacı, Murat
In this paper, the plane problem of a frictionless receding contact between an elastic functionally graded layer and two homogeneous quarter planes is considered when the graded layer is pressed against the quarter planes. The top of the layer is subjected to normal tractions over a finite segment. The graded layer is modeled as a non-homogeneous medium with a constant Poisson’s ratio and exponentially varying shear modules. The problem is converted into the solution of a Cauchy-type singular integral equation in which the contact pressure and the receding contact half-length are the unknowns using integral transforms. The singular integral equation is solved numerically using Gauss–Jacobi integration. The corresponding receding contact half-length that satisfies the global equilibrium condition is obtained using an iterative procedure. The effect of the material non-homogeneity parameter on the contact pressure and on the length of the receding contact is investigated.
AtıfScopus58WoS55OpenAlex42İncele - MakaleAçık Erişim2015Scopus SJRQ2Analysis of continuous and discontinuous cases of a contact problem using analytical method and FEM
Birinci, Ahmet; Adıyaman, Gökhan; Yaylacı, Murat; Öner, Erdal
In this paper, continuous and discontinuous cases of a contact problem for two elastic layers supported by a Winkler foundation are analyzed using both analytical method and finite element method. In the analyses, it is assumed that all surfaces are frictionless, and only compressive normal tractions can be transmitted through the contact areas. Moreover, body forces are taken into consideration only for layers. Firstly, the problem is solved analytically using theory of elasticity and integral transform techniques. Then, the finite element analysis of the problem is carried out using ANSYS software program. Initial separation distances between layers for continuous contact case and the size of the separation areas for discontinuous contact case are obtained for various dimensionless quantities using both solutions. In addition, the normalized contact pressure distributions are calculated for both cases. The analytic results are verified by comparison with finite element results. Finally, conclusions are presented.
AtıfScopus38WoS39OpenAlex36İncele - MakaleYalnız künye2015Scopus SJRQ2Analytical solution of a contact problem and comparison with the results from FEM
Öner, Erdal; Yaylaci, Murat; Birinci, Ahmet
This paper presents a comparative study of analytical method and finite element method (FEM) for analysis of a continuous contact problem. The problem consists of two elastic layers loaded by means of a rigid circular punch and resting on semi-infinite plane. It is assumed that all surfaces are frictionless and only compressive normal tractions can be transmitted through the contact areas. Firstly, analytical solution of the problem is obtained by using theory of elasticity and integral transform techniques. Then, finite element model of the problem is constituted using ANSYS software and the two dimensional analysis of the problem is carried out. The contact stresses under rigid circular punch, the contact areas, normal stresses along the axis of symmetry are obtained for both solutions. The results show that contact stresses and the normal stresses obtained from finite element method (FEM) provide boundary conditions of the problem as well as analytical results. Also, the contact areas obtained from finite element method are very close to results obtained from analytical method; disagree by 0.03-1.61%. Finally, it can be said that there is a good agreement between two methods.
AtıfScopus84WoS84OpenAlex35İncele - MakaleAçık Erişim2014Scopus SJRQ1Comparison between Analytical and ANSYS Calculations for a Receding Contact Problem
Yaylaci, Murat; Öner, Erdal; Birinci, Ahmet
This paper considers a receding contact problem for two elastic layers (with different elastic constants and heights) supported by two elastic quarter planes. The lower layer is supported by two elastic quarter planes, and the upper elastic layer is subjected to a symmetrical distributed load whose length is 2a on its top surface. It is assumed that contact between all surfaces is frictionless, and the effect of gravity force is neglected. First, the problem is formulated and solved using the theory of elasticity and integral transform technique. Using the integral transform technique and boundary conditions of the problem, the problem is reduced to a system of singular integral equations in which contact pressures and contact areas are unknown. The system of singular integral equations is solved numerically by using the Gauss-Jacobi integration formulation. Second, the receding contact problem has been developed based on the FEM ANSYS software. Two-dimensional analysis of the problem is carried out. The ANSYS and analytical results for the contact pressures, contact areas, and normal stresses (sigma(x) and sigma(y)) along the axis of symmetry are given for various dimensionless quantities. The ANSYS results are verified by comparison with analytical results. (C) 2014 American Society of Civil Engineers.
AtıfWoS50OpenAlex35İncele - MakaleYayıncıda açık erişim2014Scopus SJRQ2Continuous contact problem for two elastic layers resting on an elastic half-infinite plane
Öner, Erdal; Birinci, Ahmet
The continuous contact problem for two elastic layers resting on an elastic half-infinite plane and loaded by means of a rigid stamp is presented. The elastic layers have different heights and elastic constants. An external load is applied to the upper elastic layer by means of a rigid stamp. The problem is solved under the assumptions that all surfaces are frictionless, body forces of elastic layers are taken into account, and only compressive normal tractions can be transmitted through the interfaces. General expressions of stresses and displacements are obtained by using the fundamental equations of the theory of elasticity and the integral transform technique. Substituting the stress and the displacement expressions into the boundary conditions, the problem is reduced to a singular integral equation, in which the function of contact stresses under the rigid stamp is unknown. The integral equation is solved numerically by making use of the appropriate Gauss-Chebyshev integration formula for circular and rectangular stamp profiles. The contact stresses under the rigid stamp, contact areas, initial separation loads, and initial separation distances between the two elastic layers and the lower-layer elastic half-infinite plane are obtained numerically for various dimensionless quantities and shown in graphics and tables.
AtıfScopus24WoS25OpenAlex26İncele - MakaleAçık Erişim2014Scopus SJRQ2Solution of a receding contact problem using an analytical method and a finite element method
Öner, Erdal; Yaylaci, Murat; Birinci, Ahmet
In this study, a receding contact problem for two elastic layers supported by a Winkler foundation is handled using two different methods such as an analytical method and a finite element method. Firstly, the problem is solved analytically using linear elasticity theory. Then, in order to solve the same problem in a different way, a finite element model of the problem is created by ANSYS software, and finite element analysis of the problem is performed. The contact stresses and the contact areas at the interfaces between punch-Layer 2 and Layer 1-Layer 2 are obtained for both solutions, and it is shown that the finite element method indicates a good agreement with the analytical method.
AtıfScopus36WoS37OpenAlex25İncele