• 제목/요약/키워드: 혼합 변분 이론

검색결과 13건 처리시간 0.014초

Static and Vibration Analysis of Axisymmetric Shells Using Mixed Finite Element (혼합 유한요소를 이용한 축대칭 쉘의 정.동적해석)

  • 김진곤;노병국
    • Journal of the Computational Structural Engineering Institute of Korea
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    • 제16권2호
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    • pp.165-172
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    • 2003
  • In this study, a new and efficient harmonic axisymmetric shell element for static and dynamic analysis Is proposed. The present element considering shear strain is based on a modified mixed variational principle in which the independent unknowns are only the Quantities prescribable at the shell edges. Unlike existing hybrid-mixed axisymmetric shell elements, the present element introduces additional nodeless degrees for displacement field Interpolation In order to enhance the numerical performance. The stress parameters are eliminated by the stationary condition and the nodeless degrees are condensed out by the Guyan reduction. Through several numerical examples, the hybrid-miked shell element with the additional nodeless degrees and the consistent stress parameters is shown to be efficient and yield very accurate results for static and vibration analysis.

A New Higher-Order Hybrid-Mixed Element for Curved Beam Vibrations (곡선보의 자유진동해석을 위한 고차 혼합요소)

  • Kim Jin-Gon;Park Yong-Kuk
    • Journal of the Computational Structural Engineering Institute of Korea
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    • 제19권2호
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    • pp.151-160
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    • 2006
  • In this study, we propose a new efficient 2-noded hybrid-mixed element for curved beam vibrationshaving a uniform and non-uniform cross section. The present element considering transverse shear strain is based on Hellinger-Reissner variational principle and introduces additional nodeless degrees for displacement field interpolation in order to enhance the numerical performance. The stress parameters are eliminated by the stationary condition and then the nodeless degrees are condensed out by the Guyan reduction. In the performance evaluation process of the present field-consistent higher-order element, we carefully examine the effects of field consistency and the role of higher-order interpolation functions on the hybrid-mixed formulation. Several benchmark tests confirm e superior behavior of the present hybrid-mixed element for curved beam vibrations.

Application of High-precision Accelerometer Made in Korea to Health Monitoring of Civil Infrastructures (국산 고정밀 가속도계의 건설 구조물 적용성 평가)

  • Kwon, Nam-Yeol;Kang, Doo-Young;Sohn, Hoon
    • Journal of the Computational Structural Engineering Institute of Korea
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    • 제29권3호
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    • pp.277-283
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    • 2016
  • A high-precision force-feedback 3-axes accelerometer developed in Korea has been investigated and studied for the verification of feasibility in the computational analysis and health monitoring of civil infrastructures. Through a series of experiment, the nonlinearity, bandwidth, low-frequency signal measurement accuracy and bias characteristics of the accelerometer has been thoroughly compared to those of two accelerometers produced by two market leaders in domestic and global accelerometer market. The experiment results shows that the overall measurement performance of the accelerometer has superiority over the performance of the two accelerometers from global market leader companies. Especially, the accelerometer shows a better low-frequency signal measurement accuracy and constant bias characteristic, which are mostly required in the computational analysis and the long-term health monitoring of large-scale civil infrastructures.