• 제목/요약/키워드: Pasternak

검색결과 310건 처리시간 0.024초

집중질량 위치변화에 따른 변단면 후판의 진동해석 (Vibration Analysis of Tapered Thick Plates on Position of Concentated Mass)

  • 오숙경;이용수;김일중
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2006년도 정기 학술대회 논문집
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    • pp.681-688
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    • 2006
  • This paper has the object of investigating natural frequencies of tapered thick plate on pasternak foundation by means of finite element method and providing kinetic design data for mat of building structures. Finite element analysis of rectangular plate is done by use of rectangular finite element with 8-nodes. In order to analysis plate which is supported on pasternak foundation. the Winkler parameter is varied with 10, $10^2,\;10^3$ and the shear foundation parameter is 5, 10. This paper is analyzed varying thickness by taper ratio. The taper ratio is applied as 0.0, 0.25, 0.5, 0.75, 1.0 respectively.

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면내응력을 받는 보강 후판의 유한요소법에 의한 진동해석 (Vibration Analysis of Stiffened Thick Plate Subjected to Static Inplane Stress Using Finite Element Method)

  • 오숙경;김일중;이용수
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2004년도 춘계학술대회논문집
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    • pp.952-956
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    • 2004
  • The soil-structure interactions are caused by the point sources of explosions, deriving piles, compaction of foundations and excavations those are frequently arose in the construction sites. Thus the analysis of soil-structure interactions is one of the most important subjects in the fields of dynamic analysis and vibration control. From this viewpoint, the aim of this study is to collect the basic data for designing foundation structures throughout understanding the dynamic structural behavior, which is embodied by the dynamic analysis of soil-structure systems. In this study, the dynamic analyses of stiffened thick plates subjected to in-plane stress on elastic foundations are carried out. The foundation is modeled as Pasternak foundation that includes the continuity effect of foundations. Also both the Mindlin plate theory and Timoshenko beam-column theory are used for analyzing the thick plates and beams, respectively.

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유공 보강 후판의 진동해석 (Vibration Analysis of Stiffened Opening Thick Plate)

  • 이효진;김일중;오숙경;정진택;이용수
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2004년도 춘계학술대회논문집
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    • pp.794-798
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    • 2004
  • This paper is analysis of stiffened opening thick plate on foundation. This paper has the object of investigating natural frequencies of opening thick plates on Pasternak foundation by means of finite element method and providing Kinematic design data for mat of building structures. In this paper, vibration analysis of rectangular opening thick plate is done by use of Serendipity finite element with 8 nodes by considering shearing strain of plate. And vibration analysis of stiffener is done by used of Timoshenko beam-column element wit 3 nodes. It is shown that natural frequencies depend on not only Winkler foundation parameter but also shear foundation parameter, opening position, opening size, stiffener size.

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경사진 부분 탄성 지지부를 갖는 원통셸의 자유진동 (Free Vibrations of Cylindrical Shells on Inclined Partial Elastic Foundation)

  • 박경조;김영완
    • 한국소음진동공학회논문집
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    • 제24권3호
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    • pp.261-267
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    • 2014
  • The free vibration characteristics of cylindrical shells on inclined partial elastic foundations are investigated by an analytical method. The cylindrical shell is partially surrounded by the elastic foundations, these are represented by the Winkler or Pasternak model. The area of elastic foundation is not uniform and varies along the axial direction of the shell. The motion of shell is represented by first-order shear deformation theory(FSDT) to account for rotary inertia and transverse shear strains. The governing equation is obtained using the Rayleigh-Ritz method and a variation approach. To validate the present method, the numerical example is presented and compared with the present FEA results. The numerical results reveal that the elastic foundation has significant effect on vibration characteristics.

Post-buckling of cylindrical shells with spiral stiffeners under elastic foundation

  • Shaterzadeh, Alireza;Foroutan, Kamran
    • Structural Engineering and Mechanics
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    • 제60권4호
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    • pp.615-631
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    • 2016
  • In this paper, an analytical method for the Post-buckling response of cylindrical shells with spiral stiffeners surrounded by an elastic medium subjected to external pressure is presented. The proposed model is based on two parameters elastic foundation Winkler and Pasternak. The material properties of the shell and stiffeners are assumed to be continuously graded in the thickness direction. According to the Von Karman nonlinear equations and the classical plate theory of shells, strain-displacement relations are obtained. The smeared stiffeners technique and Galerkin method is used to solve the nonlinear problem. To valid the formulations, comparisons are made with the available solutions for nonlinear static buckling of stiffened homogeneous and un-stiffened FGM cylindrical shells. The obtained results show the elastic foundation Winkler on the response of buckling is more effective than the elastic foundation Pasternak. Also the ceramic shells buckling strength higher than the metal shells and minimum critical buckling load is occurred, when both of the stiffeners have angle of thirty degrees.

유공 후판의 자유진동해석 (Free Vibration Analysis of Opening Thick Plate)

  • 오숙경;김일중;이효진;이용수
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2003년도 추계학술대회논문집
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    • pp.808-813
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    • 2003
  • This paper is analysis of opening thick plate on foundation. This paper has the object of investigating natural frequencies of opening thick plates on pasternak foundation by means of finite element method and providing Kinematic design data for mat of building structures. In this paper, vibration analysis of rectangular opening thick plate is done by use of Serendipity finite element with 8 nodes by considering shearing strain of plate. It is shown that natural frequencies depend on not only Winkler foundation Parameter but also shear foundation parameter, opening position, opening size.

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탄성지반으로 부분 지지된 곡선보의 자유진동 (Free Vibrations of Curved Beams Partially Supported on Elastic Foundation)

  • 이병구;최규문;이태은;김무영
    • 한국농공학회지
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    • 제43권5호
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    • pp.106-115
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    • 2001
  • This paper deals with the free vibrations of horizontally curved beams partially supported on elastic foundations. Taking account of the effects of rotatory inertia and shear deformation, differential equations governing the free vibrations of such beams are derived, in which the Pasternak foundation model is considered as the elastic foundation. Differential equations are numerically solved to calculate natural frequencies and mode shapes. The experiments were performed in which the free vibration frequencies of such curved beams in laboratorial scale were measured and these results agreed quite well with the present studies. In numerical examples, the circular, parabolic, sinusoidal and elliptic curved members are considered. The parametric studies are performed and the lowest four frequency parameters are reported in tables and figures as the non-dimensional forms. Also the typical mode shapes are presented.

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집중질량 크기 변화해 따른 변단면판의 동적안정해석 (Dynamic Stability Analysis of Tapered Thick Plate on varying Concentrated Mass)

  • 김일중;오숙경
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2007년도 정기 학술대회 논문집
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    • pp.127-132
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    • 2007
  • This paper has the object of investigating dynamic stability of opening thick plates on Pasternak foundation by means of finite element method and providing Kinematic design data for mat of building structures. Finite element analysis of Tapered Thick plate is done by use of rectangular finite element with 8-nodes. In order to analysis plate which is supported on Pasternak foundation. the Winkler foundation parameter is varied with $10^2$, $10^3$ and the shear foundation parameter is 5, 10. The ratio of force to critical load is applied as 0.4, 0.6, respectively. This paper analyzed varying Tapered Ratio and Concentrated Mass.

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농촌지역 저층 조적조 건축물의 벽체 및 옹벽의 진동 안정 해석 - 전북 정읍시 ◯◯면 농촌지역 사례를 중심으로 - (Rural areas, Vibration Stability Analysis of Wall and Retaining Wall of Low-rise Masonry Buildings)

  • 이덕용;김일중
    • 한국농촌건축학회논문집
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    • 제16권4호
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    • pp.59-66
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    • 2014
  • This paper deals with vibration of plates with concentrated mass on elastic foundation. The object of investigating natural frequencies of tapered thick plate on pasternak foundation by means of finite element method and providing kinetic design data for mat of building structures. Free vibration analysis that tapered thick plate in this paper. Finite element analysis of rectangular plate is done by use of rectangular finite element with 8-nodes. In order to analysis plate which is supported on pasternak foundation. The Winkler parameter is varied with 10, $10^2$, $10^3$ and the shear foundation parameter is 5, 10. This paper is analyzed varying thickness by taper ratio. The taper ratio is applied as 0.0, 0.25, 0.5, 0.75, 1.0. And the Concentrated Mass is applied as P1, Pc, P2 respectively.

Frequency and critical fluid velocity analysis of pipes reinforced with FG-CNTs conveying internal flows

  • Ghaitani, M.;Majidian, A.
    • Wind and Structures
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    • 제24권3호
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    • pp.267-285
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    • 2017
  • This paper addresses vibration and instability of embedded functionally graded (FG)-carbon nanotubes (CNTs)-reinforced pipes conveying viscous fluid. The surrounding elastic medium is modeled by temperature-dependent orthotropic Pasternak medium. Flugge shell model is applied for mathematical modeling of structure. Based on energy method and Hamilton's principal, the motion equations are derived. Differential quadrature method (GDQM) is applied for obtaining the frequency and critical fluid velocity of system. The effects of different parameters such as volume percent of CNTs, elastic medium, boundary condition and geometrical parameters are discussed.