Akış, Tolga

Profile Picture
Profile URL
https://hdl.handle.net/20.500.14411/6697
Name Variants
Akis T.
Akis,Tolga
Tolga, Akış
Akış,T.
Akis,T.
T., Akış
Akis, Tolga
Akış, Tolga
Tolga Akış
T., Akis
T.,Akış
Akış T.
T.,Akis
Akiş T.
A.,Tolga
A., Tolga
Tolga, Akis
Akis, T
Job Title
Profesör Doktor
Email Address
tolga.akis@atilim.edu.tr
Main Affiliation
Civil Engineering
Status
Website
ORCID ID
0000-0002-6754-4497
Scopus Author ID
55144319800
Turkish CoHE Profile ID
177192
Google Scholar ID
27HKOkIAAAAJ
WoS Researcher ID
P-6181-2014

Sustainable Development Goals

NO POVERTY1
NO POVERTY
0
Research Products
ZERO HUNGER2
ZERO HUNGER
0
Research Products
GOOD HEALTH AND WELL-BEING3
GOOD HEALTH AND WELL-BEING
1
Research Products
QUALITY EDUCATION4
QUALITY EDUCATION
0
Research Products
GENDER EQUALITY5
GENDER EQUALITY
0
Research Products
CLEAN WATER AND SANITATION6
CLEAN WATER AND SANITATION
0
Research Products
AFFORDABLE AND CLEAN ENERGY7
AFFORDABLE AND CLEAN ENERGY
0
Research Products
DECENT WORK AND ECONOMIC GROWTH8
DECENT WORK AND ECONOMIC GROWTH
0
Research Products
INDUSTRY, INNOVATION AND INFRASTRUCTURE9
INDUSTRY, INNOVATION AND INFRASTRUCTURE
0
Research Products
REDUCED INEQUALITIES10
REDUCED INEQUALITIES
0
Research Products
SUSTAINABLE CITIES AND COMMUNITIES11
SUSTAINABLE CITIES AND COMMUNITIES
6
Research Products
RESPONSIBLE CONSUMPTION AND PRODUCTION12
RESPONSIBLE CONSUMPTION AND PRODUCTION
2
Research Products
CLIMATE ACTION13
CLIMATE ACTION
0
Research Products
LIFE BELOW WATER14
LIFE BELOW WATER
0
Research Products
LIFE ON LAND15
LIFE ON LAND
0
Research Products
PEACE, JUSTICE AND STRONG INSTITUTIONS16
PEACE, JUSTICE AND STRONG INSTITUTIONS
0
Research Products
PARTNERSHIPS FOR THE GOALS17
PARTNERSHIPS FOR THE GOALS
0
Research Products
Documents

28

Citations

508

h-index

13

Go to Scopus profile
Documents

27

Citations

539

Go to WoS profile
Scholarly Output

53

Articles

34

Views / Downloads

9/0

Supervised MSc Theses

16

Supervised PhD Theses

0

WoS Citation Count

539

Scopus Citation Count

651

Patents

0

Projects

0

WoS Citations per Publication

10.17

Scopus Citations per Publication

12.28

Open Access Source

10

Supervised Theses

16

JournalCount
Iranian Journal of Science and Technology, Transactions of Mechanical Engineering3
Acta Mechanica2
Journal of the Croatian Association of Civil Engineers2
Journal of the Faculty of Engineering and Architecture of Gazi University2
Mechanics Based Design of Structures and Machines2
Current Page: 1 / 6

Scopus Quartile Distribution

Competency Cloud

GCRIS Competency Cloud
Start date: 2003

Scholarly Output Search Results

Now showing 1 - 10 of 53
  • Thumbnail Image
    Article
    Citation - WoS: 3
    On the Yielding of Two-Layer Composite Spherical Pressure Vessels
    (Gazi Univ, 2017) Akis, Tolga
    The yielding of two-layer composite spherical pressure vessels under either internal or external pressure is investigated analytically in the framework of small deformations and von Mises yield criterion. It is shown for both pressure cases that depending on the material properties and sphere dimensions, different modes of plasticization may take place. Unlike the deformation behavior of a single layer spherical pressure vessel, yielding may commence at the inner layer or at the outer layer or simultaneously at both layers of the assembly.
  • Thumbnail Image
    Master Thesis
    Polimer Beton Dolgulu Alüminyum Tüplerin Mekanik Davranışının Araştırılması
    (2021) Alkarkhı, Alı Hafedh Mahmood; Akış, Tolga; Şengönül, Cemal Merih
    Bu araştırmada atık döküm kumu, epoksi ve pirinç çeltiği külünden üretilen yeni bir polimer betonla doldurulmuş alüminyum tüplerin mekanik davranışı ve sargılama etkileri incelenmiştir. Ayrıca, karbon fiberle güçlendirmenin polimer beton dolgulu alüminyum tüplerin eksenel yük kapasitesine etkisi ve her iki sargılama yönteminin temel faktörleri araştırılmıştır. Test numuneleri, 120, 150, 180 mm uzunluklarında, 40, 50, 60 ve 70 mm çaplarında veya 2, 3 ve 4 mm kalınlıklarında hazırlanmışlardır. Boş alüminyum tüp, polimer beton dolgulu alüminyum tüp ve karbon fiberle güçlendirilmiş polimer beton dolgulu alüminyum tüpler olmak üzere üç farklı gruba ayrılan deneylerde her geometri için 3 numune kullanılmıştır. Polimer beton dolgulu alüminyum tüpler ve karbon fiberle güçlendirilmiş polimer beton dolgulu alüminyum tüpler iki farklı sargılama modeli kullanılarak incelenmiştir. Tüp çapı ve kalınlığın kompozit tüplerin eksenel yük taşıma kapasitesini etkilediği görülmüştür. Tüp kalınlığının özellikle göçme biçimi üzerinde önemli bir etkiye sahip olduğu gözlenmiştir. Deney sonuçları ayrıca karbon fiberle güçlendirmenin yük taşıma kapasitesini önemli oranda artırdığını göstermiştir. Bunların yanı sıra polimer beton dolgulu alüminyum tüpler için kullanılan sargılama modelinin deneysel sonuçlarla uyum içerisinde olduğu belirlenmiştir. Karbon fiberle güçlendirilmiş polimer beton dolgulu alüminyum tüpler için kullanılan sargılama modeli ise deney sonuçları göz önünde bulundurulduğunda oldukça güvenli tarafta kalmıştır.
  • Thumbnail Image
    Article
    Citation - WoS: 20
    Citation - Scopus: 20
    The Stress Response of Partially Plastic Rotating Fgm Hollow Shafts: Analytical Treatment for Axially Constrained Ends
    (Taylor & Francis inc, 2006) Eraslan, Ahmet N.; Akis, Tolga
    analytical solutions to estimating the elastoplastic response of rotating functionally graded (FGM) hollow shafts with fixed ends are presented. The modulus of elasticity, as well as the uniaxial yield limit of the shaft material, are assumed to vary nonlinearly in the radial direction. The plastic model is based on Tresca's yield criterion, its associated flow rule, and ideal plastic material behaviour. Elastic, partially plastic, fully plastic, and residual stress states are investigated. It is shown that the elastoplastic stress response of a rotating FGM hollow shaft is affected significantly by the nonhomogeneity of the material. Unlike the case of a homogeneous hollow shaft, plastic deformation may commence at the inner surface, at the outer surface, or simultaneously at both surfaces. Accordingly, each case requires different mathematical treatment to arrive at its partially plastic solution. It is also shown that, by taking a numerical limit, the complete FGM solution presented herein converge to the solution of a homogeneous rotating shaft.
  • Thumbnail Image
    Article
    Citation - WoS: 23
    Citation - Scopus: 30
    On the Elastic-Plastic Deformation of a Rotating Disk Subjected To a Radial Temperature Gradient
    (Marcel dekker inc, 2003) Eraslan, AN; Akis, T
    Elastic-plastic stress distribution in a nonisothermal rotating annular disk is analyzed by the use of Tresca and von Mises criteria. An energy equation that accounts for the convective heat transfer with a variable heat transfer coefficient is modeled. For a given angular velocity, the steady temperature distribution in the disk is obtained by the analytical solution of the energy equation. Tresca yield criterion and its associated flow rule are used to obtain the analytical stress distributions for a linearly hardening material. A computational model is developed to analyze elastic-plastic deformations of the disk using von Mises yield criterion and its flow rule. This model incorporates Swift's hardening law to simulate linear as well as nonlinear hardening material behavior. It is shown that the stress distribution in the disk is affected significantly by the presence of the temperature gradient.
  • Thumbnail Image
    Article
    Citation - Scopus: 13
    Deformation Analysis of Elastic-Plastic Two Layer Tubes Subject To Pressure: an Analytical Approach
    (2004) Eraslan,A.N.; Akiş,T.
    Analytical solutions are obtained for axisymmetric elastic-plastic deformations in tightly fitted concentric tubes with fixed ends subjected to either internal or external pressure. Tresca's yield criterion and its associated flow rule are used to estimate the elastic-plastic response of the assembly. The closed form solutions for all elastic-plastic deformation stages are obtained by assuming linear hardening material behavior. Some numerical examples are handled using the mechanical properties of real engineering materials.
  • Thumbnail Image
    Article
    Numerical Solutions of a Simplified Reactive Flow Model
    (2007) Eraslan,A.N.; Akiş,T.
    A simple model problem well describing the interaction of convection, diffusion and fast chemistry in laminar reactive flows is formulated. The model involves a minimum number of parameters which are chosen to be close to those in real problems so that the strong interaction of various important processes taking place in reactive flows can be evaluated. Dimensionless forms of the strongly coupled model equations are solved numerically using the collocation method. Steady-state solutions are obtained as the time-asymptotic solution of unsteady problems by using arbitrary initial profiles for temperature. Parametric analyses are performed to investigate the effect of important model parameters on the calculated temperature and concentration distributions.
  • Thumbnail Image
    Article
    Citation - WoS: 10
    Citation - Scopus: 11
    Influence of Cement Replacement by Calcinated Kaolinitic and Montmorillonite Clays on the Properties of Mortars
    (Springer Heidelberg, 2023) Al-Noaimat, Yazeed A. A.; Akis, Tolga
    This study aims to investigate the decomposition and pozzolanic reactivity of two different clays (kaolinitic and montmorillonite) from different origins and to determine their effects after calcination on the properties of cement mortars when used to replace Portland cement partially. Mineralogical and chemical compositions of the clay samples were determined using XRD (X-ray Diffractometer) and XRF (X-ray Fluorescence) tests, respectively. TG-DTA (Thermogravimetry-Differential Thermal Analyses) was used to determine the temperature profiles and the burning temperatures of the clays. The density and fineness of the burnt clays were also determined. In order to investigate the optimum material properties, different burning temperatures and replacement levels were considered. It was found that for all temperatures, the two burnt clays possess good pozzolanic activity. The highest compressive strength and lowest water absorption capacity were achieved when the clay determined as kaolinitic was burned at 700 & DEG;C and with 10% replacement level. While for the clay determined as montmorillonite, the optimum properties were obtained at 700 & DEG;C with a 20% substitution level. Kaolinite had better pozzolanic reactivity than montmorillonite, achieving higher strength performance with lower water absorption when partially replaced with cement. Moreover, it had compressive strength values even higher than plain cement.
  • Thumbnail Image
    Article
    Citation - WoS: 1
    Citation - Scopus: 3
    Modeling of Asymmetric Shear Wall-Frame Building Structures
    (Architectural inst Japan, 2009) Akis, Tolga; Tokdemir, Turgut; Yilmaz, Cetin
    Based on the conventional wide column analogy, two different three-dimensional shear wall models for open and closed sections are proposed. These approximate models are verified in comparison to not only the results available in the literature but also the ones obtained by Using models containing shell elements. With the help of these new models five different groups of shear wall-frame structures with different floor plans and different heights are analyzed. The first three natural vibration periods are determined and time history analyses are performed. The results Of these computations are observed to be in good agreement with those obtained by detailed models containing shell elements.
  • Thumbnail Image
    Article
    Citation - WoS: 1
    Citation - Scopus: 1
    Metaheuristic Optimization of Rotating Multilayer Composite Tubes Under Internal Heating and Pressure
    (Springer, 2022) Azad, Saeid Kazemzadeh; Akis, Tolga; Kazemzadeh Azad, Saeid
    Although analysis/design of multilayer assemblies has been always an active field of research, works on the optimal design of rotating multilayer composite tubes are very limited. This paper addresses the design optimization of rotating multilayer composite tubes under internal heating and pressure. For determining the structural responses, analytical solutions are provided based on different boundary conditions. The automated selection of optimal material as well as thickness optimization of pressurized multilayer assemblies is carried out under different angular speed and internal heating conditions using a metaheuristic algorithm. The corresponding optimum design for each angular speed as well as internal heating condition is sought, and the numerical results are discussed. The study provides general guidelines for conceptual design of rotating multilayer composite tubes subjected to internal heating and pressure.
  • Thumbnail Image
    Article
    Citation - WoS: 33
    Citation - Scopus: 36
    Exact Solution of Rotating Fgm Shaft Problem in the Elastoplastic State of Stress
    (Springer, 2007) Akis, Tolga; Eraslan, Ahmet N.
    Plane strain analytical solutions to estimate purely elastic, partially plastic and fully plastic deformation behavior of rotating functionally graded (FGM) hollow shafts are presented. The modulus of elasticity of the shaft material is assumed to vary nonlinearly in the radial direction. Tresca's yield criterion and its associated flow rule are used to formulate three different plastic regions for an ideal plastic material. By considerina different material compositions as well as a wide range of bore radii, it is demonstrated in this article that both the elastic and the elastoplastic responses of a rotating FGM hollow shaft are affected significantly by the material nonhomogeneity.