Loading...
Search for: in-plane
0.006 seconds
Total 47 records

    Optimal design of stiffened plates for buckling under in-plane forces and bending moments

    , Article Proceedings of the Eight International Conference on Civil and Structural Engineering Computing, Vienna, 19 September 2001 through 21 September 2001 ; 2001 , Pages 83-84 ; 0948749768 (ISBN) Ghorashi, M ; Askarian, A ; Gashtasby, M ; Sharif University of Technology
    2001
    Abstract
    The optimal design of stiffened plates for buckling under in-plane forces and bending moments was presented. The virtual work principle was applied in order to calculate the buckling coefficient and the critical load factor of the stiffened plates. It was observed that the buckling coefficient is a function of the displacement coefficients  

    Predictive tri-linear benchmark curve for in-plane behavior of adobe walls

    , Article International Journal of Architectural Heritage ; Volume 9, Issue 8 , Nov , 2015 , Pages 986-1004 ; 15583058 (ISSN) Rafsanjani, S. H ; Bakhshi, A ; Ghannad, M. A ; Yekrangnia, M ; Soumi, F ; Sharif University of Technology
    Taylor and Francis Inc  2015
    Abstract
    In the present study, numerical simulations are conducted to estimate the in-plane response of adobe walls subjected to pseudo-static cyclic loading based on the finite element code ABAQUS. The simplified micro-modeling approach is adopted and an interface model reported in ABAQUS material library is applied as material model for zero-thickness interface elements. The comparison between obtained results and field test data results in good agreement. Parametric studies are carried out to evaluate the effectiveness of independent parameters changes on response of adobe walls. It is noted that mechanical properties of joints and adobe units play an active role on in-plane behavior of walls. A... 

    In-plane free vibrations of annular elliptic and circular elastic plates of non-uniform thickness under classical boundary conditions

    , Article International Review of Mechanical Engineering ; Volume 4, Issue 1 , 2010 , Pages 112-119 ; 19708734 (ISSN) Hassani, A ; Hojjati, M. H ; Fathi, A. R ; Sharif University of Technology
    Abstract
    This paper presents a formulation for in-plane modal characteristics of non-uniform thickness annular elliptic and circular plates for all classical boundary conditions. The investigations are performed for elastic and isotropic annular elliptic plates on the basis of two- dimensional linear plane stress theory of elasticity. Two-dimensional boundary characteristic orthogonal polynomials (BCOP) are used in the Rayleigh-Ritz method to obtain the natural frequencies and associated mode shapes. The proposed method, not only can find solution for those simple cases of annular circular plates available in literature as a simplified case study, but also it finds some natural frequencies which can... 

    On the rolling contact problem of two elastic solids with graded coatings

    , Article International Journal of Mechanical Sciences ; Volume 64, Issue 1 , 2012 , Pages 62-81 ; 00207403 (ISSN) Guler, M. A ; Alinia, Y ; Adibnazari, S ; Sharif University of Technology
    2012
    Abstract
    In this study, the rolling contact problem of two elastically similar cylinders coated with functionally graded materials is investigated. The singular integral equations approach is utilized to extract the governing equations of the problem. The governing equations are discretized into systems of algebraic equations by virtue of the Gauss-Chebyshev integration method. Comprehensive parametric study is performed to examine the effects of mechanical properties, coating thickness and external loads on the surface stress components, stick/slip transition, creep ratio and power loss. This study aimed to emphasize the capability of graded materials in improving the rolling contact fatigue of... 

    Schramm Loewner Evolutions (SLE)

    , M.Sc. Thesis Sharif University of Technology Jamshidpey, Arash (Author) ; Zohouri Zangeneh, Bijan (Supervisor)
    Abstract
    The purpose of this thesis is to introduce a very important and recent branch of probability, ”SLE”, its relation to some discrete models in statistical physics, motivation, geometrical intuition and some of its important properties. In chapter 1, we introduce three discrete models: Self Avoiding Walk (SAW), Loop Erased Random Walk (LERW), and Percolation that have an important role in the thesis. In chapter 2, we set up the concept of SLE on two of these models. Required preliminaries from complex analysis and Loewner equations will be studied in chapter 3, and then, in chapter 4 we will define Chordal and Radial SLE. Studying some important properties of SLE is the subject of chapter 5. In... 

    In-plane and out-of-plane waves in nanoplates immersed in bidirectional magnetic fields

    , Article Structural Engineering and Mechanics ; Volume 61, Issue 1 , 2017 , Pages 65-76 ; 12254568 (ISSN) Kiani, K ; Gharebaghi, S. A ; Mehri, B ; Sharif University of Technology
    Techno Press  2017
    Abstract
    Prediction of the characteristics of both in-plane and out-of-plane elastic waves within conducting nanoplates in the presence of bidirectionally in-plane magnetic fields is of interest. Using Lorentz's formulas and nonlocal continuum theory of Eringen, the nonlocal elastic version of the equations of motion is obtained. The frequencies as well as the corresponding phase and group velocities pertinent to the in-plane and out-of-plane waves are analytically evaluated. The roles of the strength of in-plane magnetic field, wavenumber, wave direction, nanoplate's thickness, and small-scale parameter on characteristics of waves are discussed. The obtained results show that the in-plane... 

    Numerical Modeling of In-plane Behavior of Adobe Walls Strengthened by Various Retrofitting Methods Under Cyclic Loading

    , M.Sc. Thesis Sharif University of Technology Hashemi Rafsanjani, Ebrahim (Author) ; Bakhshi, Ali (Supervisor) ; Ghannad, Mohammad Ali (Supervisor)
    Abstract
    Adobe structures are considered as masonry structures which are out of scope of 2800 Iranian code. Due to this code, since these structures are made of weak materials, they do not have a considerable resistance to earthquakes. Since these structures can be found all around Iran; therefore, seismic study of walls as an important component of these structures, is, indeed, necessary. During this study, cyclic tests on three types of adobe walls, without opening, with window-opening, and with door-and-window-opening with a scale of 2:3 were done to study their in-plane behavior and also their failure modes. Based on our observations, in these walls, because of small ratio of height to length,... 

    Influence of Floor Diaphragm on Seismic Response of RC Structures

    , M.Sc. Thesis Sharif University of Technology Masoumi, Hassan (Author) ; Khaloo, Alireza (Supervisor)
    Abstract
    Modeling is one of the most important steps in analysis and design of structures. Most of the time behavior of floor diaphragms is assumed completely rigid in their plane in order to simplicity in practical design. Although this assumption leads to acceptable results in analysis and design of conventional buildings, erroneous results may assess in some particular buildings—for instance narrow buildings with stiff end walls. Accordingly, behavior of these buildings in future earthquakes opposes those were predicted in design phase, and they are so vulnerable since in-plane deflection of floor diaphragms are striking which cannot be ignored. This thesis investigates the significance of... 

    Numerical Studies of In-Plane and Out-of-Plane Behavioral Interaction of Masonry Walls

    , M.Sc. Thesis Sharif University of Technology Soleimanzadeh, Amir (Author) ; Bakhshi, Ali (Supervisor)
    Abstract
    Nowadays, over seventy percent of buildings in the world are Structures which show a weak and often vulnerable behavior. Therefore, cognition and perception of the behavior of these types of structures are of important matters.Brick walls are the most important components of brick structures which have two in-plane and out-of-plane failure mode that are the common failure modes. Up to this point, lots of studies taking into account in-plane and out-of-plane behavior of brick walls individually have yet been carried out. However, the way these two modes could affect each other has not been studied effectively and there is no precise vision about this issue in the engineering society.... 

    Mechanical properties of graphene cantilever from atomic force microscopy and density functional theory

    , Article Nanotechnology ; Volume 21, Issue 18, Article number 185503 , 2010 ; 09574484 Rasuli, R. (Reza) ; Iraji Zad, A. (Azam) ; Ahadian, M. M ; Sharif University of Technology
    Abstract
    We have studied the mechanical properties of a few-layer graphene cantilever (FLGC) using atomic force microscopy (AFM). The mechanical properties of the suspended FLGC over an open hole have been derived from the AFM data. Force displacement curves using the Derjaguin–Müller–Toporov (DMT) and the massless cantilever beam models yield a Young modulus of Ec ~ 37, Ea ~ 0.7 TPa and a Hamakar constant of ~ 3 × 10 − 18 J. The threshold force to shear the FLGC was determined from a breaking force and modeling. In addition, we studied a graphene nanoribbon (GNR), which is a system similar to the FLGC; using density functional theory (DFT). The in-plane Young's modulus for the GNRs were calculated... 

    Anomalous diffusion of proteins in sheared lipid membranes

    , Article Physical Review E - Statistical, Nonlinear, and Soft Matter Physics ; Volume 88, Issue 3 , September , 2013 ; 15393755 (ISSN) Khoshnood, A ; Jalali, M. A ; Sharif University of Technology
    2013
    Abstract
    We use coarse grained molecular dynamics simulations to investigate diffusion properties of sheared lipid membranes with embedded transmembrane proteins. In membranes without proteins, we find normal in-plane diffusion of lipids in all flow conditions. Protein embedded membranes behave quite differently: by imposing a simple shear flow and sliding the monolayers of the membrane over each other, the motion of protein clusters becomes strongly superdiffusive in the shear direction. In such a circumstance, the subdiffusion regime is predominant perpendicular to the flow. We show that superdiffusion is a result of accelerated chaotic motions of protein-lipid complexes within the membrane voids,... 

    Design and manufacturing of ultrasonic motor with in-plane and out-of-plane bending vibration modes of rectangular plate with large contact area

    , Article Measurement: Journal of the International Measurement Confederation ; Volume 109 , 2017 , Pages 425-431 ; 02632241 (ISSN) Dabbagh, V ; Sarhan, A. A. D ; Akbari, J ; Mardi, N. A ; Sharif University of Technology
    Abstract
    Ultrasonic motor working with coupled in-plane and out-of-plane vibration modes of rectangular plate is proposed and experimentally investigated. Thanks to its unique configuration, proposed motor provides large contact area between stator and rotor of motor which can reduce wear and enhance motor life-time. The proposed motor is designed using finite element method and according to the design, a prototype is fabricated and its working characteristics such as speed, normal and driving force and working frequency are measured. Overall dimension of designed prototype is 49 × 14 × 2 mm, working frequency of motor is 49.6 kHz, no-load speed and stall force of motor are 122 rpm and 0.32 mN m at... 

    Effect of the FRP sheet's arrays and NSM FRP bars on in-plane behavior of URM walls

    , Article Journal of Building Engineering ; Volume 20 , 2018 , Pages 679-695 ; 23527102 (ISSN) Jafari, A ; Vatani Oskouei, A ; Bazli, M ; Ghahri, R ; Sharif University of Technology
    Elsevier Ltd  2018
    Abstract
    This paper studies the results of compression diagonal tests conducted on a series of retrofitted and non-retrofitted small-scale masonry walls (which are also known as wallettes). Wallettes with the same characteristics and mechanical properties of large masonry walls were retrofitted by using two arrays of glass fiber reinforcement polymer (GFRP) sheets (grid and diagonal), two arrays of carbon fiber reinforcement polymer (CFRP) sheets (grid and diagonal), and near surface mounted bars (steel and GFRP). FRP sheets were applied to both surfaces of the wallettes, and rebar was mounted onto one of the surfaces in two horizontal and two vertical arrangements. All of the methods significantly... 

    Tree-dimensional Free Vibration of Nano-Composite Plates with Arbitrary Geometry within Couple Stress Theory

    , M.Sc. Thesis Sharif University of Technology Forouzan, Bahareh (Author) ; Mohammadi Shoja, Hossein (Supervisor)
    Abstract
    Based on Hamilton’s principle, a three-dimensional semi-analytical method for the analysis of free vibration of a nano-composite plate within the couple stress theory is developed. Computation of dynamic behavior as well as natural frequencies and mode shapes is interested. In this method, the mechanical displacement functions, in each layer, are defined as product of a base function and a three-dimensional polynomial with unknown coefficients. The base functions are defined with respect to the kinematical boundary condition and the domain geometry. The mode shapes will be obtained and the accuracy of the present approach is demonstrated by comparison it in both classical elasticity and... 

    Investigation of Cyclic Behavior of Adobe Walls Strengthened With Various Retrofitting Methods

    , M.Sc. Thesis Sharif University of Technology Soumi, Farzad (Author) ; Bakhshi, Ali (Supervisor) ; Ghannad, Mohammad Ali (Supervisor)
    Abstract
    Adobe structures are considered as masonry structures which are out of scope of 2800 Iranian code. Due to this code, since these structures are made of weak materials, they do not have a considerable resistance to earthquakes. Since these structures can be found all around Iran; therefore, seismic study of walls as an important component of these structures, is, indeed, necessary. During this study, cyclic tests on three types of adobe walls, without opening, with window-opening, and with door-and-window-opening with a scale of 2:3 were done to study their in-plane behavior and also their failure modes. Based on our observations, in these walls, because of small ratio of height to length,... 

    Simulation of in Plane and Lateral Vibration of a Graphene Plate, Based on the Clasic Plate Theory and the most General form of Strain Gradient Theory and Deriving the Constitutive Law Parameters from Molecular Mechanic Parameters

    , M.Sc. Thesis Sharif University of Technology Hassanpour, Saba (Author) ; Dehghani Firouzabadi, Rohollah (Supervisor)
    Abstract
    Here the differential equations of a Graphene sheet deformation is determined by making use of the most general form of first Strain Gradient Elasticity (SGE) theory. In order to derive the equations of in-plane and out-of-plane deformations, the matrix representation of Strain Gradient constitutive law is used. Vibration of the nano-plate is studied by modeling the plate based on Kirchhoff theory and application of variation of energy, therefor the in-plane and out-of-plane vibration of the nano-plate is found through Navier analytical solution. After all natural frequencies are obtained based on SGE parameters. SGE parameters are determined by calculating the potential of a representative... 

    On the Seismic Behavior of RC Frames with Brick Infilled Walls with Opening, Retrofitted by FRP

    , M.Sc. Thesis Sharif University of Technology Paeini Vayghan, Mostafa (Author) ; Rahimzadeh Rofooei, Fayaz (Supervisor)
    Abstract
    Wall systems are an essential part of the buildings and their capacity should be properly considered in their design. However, the seismic behavior of building systems with in-filled walls and their interaction is a very complex issue, yet to be understood. Using the in-filled walls in the buildings without including them in the design process changes the whole behavior of the structural system as well as their failure mechanism under earthquake excitations. On the other hand, there have been extensive researches on rehabilitation of the structures with in-filled walls or designing them as the main or one of the lateral load carrying systems against seismic input. In this research, first the... 

    Design of Fillet Welds in Plastic State

    , M.Sc. Thesis Sharif University of Technology Ezzatnejad, Shahriyar (Author) ; Maleki, Shervin (Supervisor)
    Abstract
    Nowadays, many structural engineers use fillet welds in their designs because of their high strength and affordability. In these welds, eccentric loadings either out-of-plane or in-plane create complex condition in welds from stress point of view. To determine the capacity of such fillet welds different methods have been proposed over time. For instance, the method approved by AISC is the Elastic method. This method when combined with load factors, as required by the LRFD design method, yields very conservative designs for fillet welds. Therefore, in this project, we try to propose the plastic method for welds under eccentric loadings. This method is more economical than the elastic method... 

    Free vibration analysis of multilayered functionally graded composite cylinder

    , Article ASME International Mechanical Engineering Congress and Exposition, Proceedings (IMECE), 12 November 2010 through 18 November 2010 ; Volume 13 , 2010 , Pages 441-450 ; 9780791844502 (ISBN) Kargarnovin, M. H ; Hashemi, M ; Sharif University of Technology
    Abstract
    Free vibration of multilayered composite cylinder which volume fraction of fiber varies according to power law in longitudinal direction has been studied. Rule of mixture model and reverse of that are employed to represent elastic properties of this fibrous functionally graded composite. Straindisplacement relations employed are based on Reissner- Naghdi-Berry's shell theory. The displacement finite element model of the governing equations of motion is derived by writing weak form of them. The Lagrangian shape functions for in-plane displacements and Hermitian shape functions for displacement in normal direction to the surface of mid-plane are utilized by defining a conformal quadrilateral... 

    Influence of diaphragm opening on seismic response of rectangular RC buildings with end shear walls

    , Article Scientia Iranica ; Volume 23, Issue 4 , 2016 , Pages 1689-1698 ; 10263098 (ISSN) Khaloo, A. R ; Masoomi, H ; Nozhati, S ; Mohamadi Dehcheshmeh, M ; Sharif University of Technology
    Sharif University of Technology  2016
    Abstract
    Routinely, behavior of floor diaphragms is assumed completely rigid in their plane, which leads to erroneous results in analysis and design of some particular buildings. In this study, 4-story RC buildings, with end shear walls and plan aspect ratio of 3, are considered in order to investigate the influence of diaphragm openings on their seismic response. It is concluded that although in-plane floor flexibility has enormous effects on pre-yielding part of pushover curve, it has no influence on post-yielding part of that. Furthermore, the opening beside shear walls has crucial impact on response of building. Hence, it would be better off avoiding opening near the shear walls; if not, the...