• Title/Summary/Keyword: initial element

Search Result 1,684, Processing Time 0.029 seconds

A Study on the Fatigue Strength Analysis of Hub in a Wind Turbine (풍력터빈 허브의 피로 강도 해석에 대한 연구)

  • Koh, Jang-Wook;Kim, Hyang-Ki;Ahn, Kyoung-Min;Choi, Won-Ho
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2006.11a
    • /
    • pp.265-268
    • /
    • 2006
  • Performed fatigue strength analysis for Hub to get the targeted service life of 20 years. ANSYS is used to analysis. The major structure of bearing which connect the hub and blades is modeled using the element of LINK10. To represent the stiffness of LINK10 element, initial strain and diameter of LINK10 element is applied. Prior to calculating the fatigue damages, the influence matrix is extracted from the unit loads. The target service life of 20 years is achieved from the Analysis results.

  • PDF

An Analysis of English Reduplicative compounds (영어 중첩복합어 분석)

  • 김형엽
    • Lingua Humanitatis
    • /
    • v.2 no.1
    • /
    • pp.303-314
    • /
    • 2002
  • The main purpose of this paper is to show how Jespersen analyzed the date of English compound related with reduplication. Especially dealing with the compound words he classified the examples related with reduplication as a separate part and attempted to account for the patters based on the structure of the first syllable constituting the initial part of the second element in a compound word. 1 tried to explain the peculiar shape of the reduplicational pattern in English based on the Optimality Theory, especially the method of 'melodic overwriting' of McCarthy(1997). According to the analysis the initial part of the second element of a compound has to be stipulated before reduplication occurs. When the reduplicant has to be decided at the first syllable of the second element, the form which is stipulated to take the position comes to appear at the post instead of repeating the morphemic shape of the first syllable at the first element of the word.

  • PDF

Efficient finite element analysis for the ultimate strength estimation of cylindrical structure (원통구조의 최종강도 추정을 위한 효율적인 유한요소해석)

  • 박치모
    • Journal of Ocean Engineering and Technology
    • /
    • v.10 no.4
    • /
    • pp.28-37
    • /
    • 1996
  • A finite element analysis code considering elasto-plastic large deformation is developed to predict the ultimate strength of circular cylinders subject to external pressure loading by introducing a new type of axisymmetric shell element which can take into account the plasticity effect due to the circumferential bending while drastically saving the computing efforts compared with the tree dimensional finite element analysis. It is observed that analsis results of present approach show good agreement with the test results of previous works. Parametric study gives the effects of initial imperfections on ultimate strength ahd this information is recommended to be used to modify the actual test data to the ones which can be used more reasonably in making empirical design formulas.

  • PDF

Static behavior of nonlocal Euler-Bernoulli beam model embedded in an elastic medium using mixed finite element formulation

  • Nguyen, Tuan Ngoc;Kim, Nam-Il;Lee, Jaehong
    • Structural Engineering and Mechanics
    • /
    • v.63 no.2
    • /
    • pp.137-146
    • /
    • 2017
  • The size-dependent behavior of single walled carbon nanotubes (SWCNT) embedded in the elastic medium and subjected to the initial axial force is investigated using the mixed finite element method. The SWCNT is assumed to be Euler-Bernoulli beam incorporating nonlocal theory developed by Eringen. The mixed finite element model shows its great advantage of dealing with nonlocal behavior of SWCNT subjected to a concentrated load owing to the existence of two coefficients ${\alpha}_1$ and ${\alpha}_2$. This is the first numerical approach to deal with a puzzling fact of nonlocal theory with concentrated load. Numerical examples are performed to show the accuracy and efficiency of the present method. In addition, parametric study is carefully carried out to point out the influences of nonlocal effect, the elastic medium, and the initial axial force on the behavior of the carbon nanotubes.

Repaired concrete columns with fiber reinforced thixotropic mortar: experimental & FEA approach

  • Achillopoulou, Dimitra V.;Arvanitidou, Konstantinia C.;Karabinis, Athanasios I.
    • Computers and Concrete
    • /
    • v.15 no.1
    • /
    • pp.73-88
    • /
    • 2015
  • Following previous studies, the current paper describes the results of an experimental program concerning the repair of reinforced concrete columns by thixotropic pseudo plastic mortar, preformed to analyze and quantify the influence of initial construction damage to the behavior of the repaired element. Five columns (section scale 1:2) were designed according to the minimum requirements of reinforcement of ductility orientated codes' design with variables the percentages of initial construction damages. All were tested in axial compression with repeated cycles up to failure. For comparison reasons, another one of the same characteristics, yet healthy, was constructed and tested as a reference specimen. A numerical study (Finite Element Analysis) was conducted for further investigation of the behavior of the thixotropic mortar as repair material. The results indicate that: a) surpassing a specific amount of damage, columns even suitably repaired present lower strain capacity, b) finite element analysis present the same way of deboning of the repaired material taking into consideration the buckling of the reinforcement bars.

Initial Shape Finding and Stress-Deformation Analysis of Pretensioned Membrane Structures with Triangular Constants Strain Element (TCS요소론 이용한 인장 막구조물의 초기명상해석 및 응력변형해석)

  • Ko, Hyuk-Jun;Song, Pyung-Hun;Song, Ho-San
    • 한국공간정보시스템학회:학술대회논문집
    • /
    • 2004.05a
    • /
    • pp.230-237
    • /
    • 2004
  • In this study, equation of finite element is formulated to analyze relations of large deformation-small deformation considering geometrical nonlinear for membrane structure. Total Lagrangian Formulation(TLF) is introduced to formulate theory and equation of motion considering Triangular Constant Strain(TCS) element in finite, element analysis is formulated. Finite element program is made by equation of motion considering TLF. This study analyzed a variety of examples, so compared with the past results.

  • PDF

Technology for Initial Design and Analysis of Vehicle Pillar Structures for Vibration (저진동 차체의 필라 설계 및 최전화 기법)

  • 임홍재;이상범
    • Journal of KSNVE
    • /
    • v.5 no.3
    • /
    • pp.395-402
    • /
    • 1995
  • In general low frequency vibration characteristics like an idleshake is mainly influeced by pillar section properties and joints. So the design technique development of vehicle pillar structures is required to initial design and vehicle development stage. In this paper to develop pillar structure design technique considering low frequency vibration characteristics, strain energy method, design sensitivity analysis method, and design optimization method using commercial finite element analysis program and optimization program are presented.

  • PDF

Dynamic Nonlinear Analysis of Marine Cables Under Wave Force and Earthquake Force (파랑하중 및 지진하중을 받는 해양케이블의 동적 비선형 해석)

  • 김문영
    • Proceedings of the Earthquake Engineering Society of Korea Conference
    • /
    • 1999.04a
    • /
    • pp.292-299
    • /
    • 1999
  • In order to investigate dynamic behaviors of marine cables under wave and earthquake forces a geometric nonlinear. F, E formulation of marine cables is presented and tangent stiffness and mass matrices for the isoparametric cable element are derived, The initial equilibrium state of cables subjected to self -weights and current forces is determined and free vibration and dynamic nonlinear analysis of cable structures under additional environmental loads are performed based on the initial configuration Challenging examples are presented and discussed in order to demonstrate the feasibility of the present finite element method and investigate dynamic nonlinear behaviors of marine cables.

  • PDF

A Study on compressive behavior of laminated plates with initial delamination (박리가 발생된 적층평판의 압축 거동에 관한 연구)

  • Lee, Nam-Ju;Jo, Yong-Oug
    • Proceeding of EDISON Challenge
    • /
    • 2016.03a
    • /
    • pp.167-174
    • /
    • 2016
  • Recently laminated plates like composite materials has been used in a various field to grow the specific strength of the composition. However, delamination area caused by barely visible impact damage has potential risk that it can raise buckling of the delaminated plate. Because it can interrupt compressive behavior of laminated plates and reduce their strength, the whole structure can't be constituted by these materials. Many studies assume that behavior of the delaminated plate which is in lamanated plates equals theoretical buckling but their actual motion doesn't coincide because of initial imperfections of materials like deflection, residual stress, eccentricity and so on. In this paper, we change laminated plates with initial delamination into a beam of rectangular cross section with the initial crack and analyze compressive behavior according to initial imperfections through finite element method(FEM). Consequently analysis results show that behavior of laminated plates involving delamination differs from ideal buckling of the delaminated plate in actual conditions and we can predict its motion through imperfections relationship.

  • PDF

Study on Ultimate Behavior of Steel Transmission Tower with Residual Stress and Initial Imperfection (잔류응력과 초기변형을 고려한 송전철탑의 비선형 극한거동에 관한 해석적 연구)

  • Chang, Jin Won;Kim, Seung Jun;Park, Jong Sup;Kang, Young Jong
    • Journal of Korean Society of Steel Construction
    • /
    • v.20 no.3
    • /
    • pp.421-435
    • /
    • 2008
  • This paper presents an investigation on the ultimate behavior of a transmission tower using nonlinear analyses inconsideration of residual stress and initial imperfection. Main members, such as main post, horizontal member and diagonal member of the transmission tower were modeled using beam element. Moreover, submembers of the transmission tower were modeled using truss element. ABAQUS (2004) program was used to perform finite element analyses. Initial condition options of the ABAQUS program considering initial stress and imperfection were used in this study. Before performing the analysis of the total transmission tower, simple angle section models using beam or plate/shell element w ere investigated to verify the appropriateness of ABAQUS analysis models and options. According to the verification results, the beam element was used for nonlinear analyses of the transmission tower. From nonlinear analyses results, buckling failure was in the main member of the leg part because of ${P-{\triangle}}$ effect at that point. Also, this paper includes significant results to define real structural failure modes and quantitative values. This study should be used in the development of a reasonable and economic design method for transmission towers.