• Title, Summary, Keyword: 전달행렬법

Search Result 108, Processing Time 0.032 seconds

An Analysis of Continuous Beam by Material Non-linear Transfer Matrix Method (재료비선형 전달행렬법에 의한 연속보의 해석)

  • Seo, Hyun Su;Kim, Jin Sup;Kwon, Min Ho
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.15 no.1
    • /
    • pp.77-84
    • /
    • 2011
  • This study is to develop nonlinear analysis algorithm for transfer matrix method, which can be applied to continuous beam analysis. Gauss-Lobatto integral rule is adopted and the transfer matrix is derived from stiffness matrix. In the transfer matrix method, the system equation has a constant number of unknowns regardless of number of D.O.F. Therefore, the transfer matrix method has computational efficiencies not only in linear elastic analysis but also in nonlinear analysis. To verify the developed method, the analysis results of several examples are compared with commercial code in moment-curvature, moment-displacement and load-displacement relation.

Influence Lines of a Portal Frame with Joint Translations by Transfer Matrix Method (전달행렬법에 의한 변위를 허용하는 문형라멘의 영향선해석)

  • 남문희;하대환
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.14 no.1
    • /
    • pp.29-34
    • /
    • 2001
  • 구조물설계에 있어서 영향선은 최대반력, 최대전단력, 최대휨모멘트 등을 계산하는데 아주 유용하게 사용된다. 모멘트분배법, 인도행렬법, 전달행렬법, 그리고 Muller-Breslau 원리에 의한 단순보와 연속보의 영향선은 잘 알려져 있고 또 교량공학에서 널리 사용되고 있다. 그러나 변위를 허용하는 특별한 구조물의 영향선을 계산할 경우에는 약간의 어려움이 있다. 이 연구에서는 절점변위를 허용하는 문형라멘의 영향선을 전달행렬법에 의하여 구하고 유한요소법에 의하여 얻은 영향선과 비교하였고 그 결과는 좋은 일치를 보이고 있다.

  • PDF

An Analysis of Cylindrical Tank of Elastic Foundation by Transfer Matrix and Stiffness Matrix (전달행렬과 강성행렬에 의한 탄성지반상의 원형탱크해석)

  • 남문희;하대환;이관희;장홍득
    • Computational Structural Engineering
    • /
    • v.10 no.1
    • /
    • pp.193-200
    • /
    • 1997
  • Even though there are many analysis methods of circular tanks on elastic foundation, the finite element method is widely used for that purpose. But the finite element method requires a number of memory spaces, computation time to solve large stiffness equations. In this study many the simplified methods(Analogy of Beam on Elastic Foundation, Foundation Stiffness Matrix, Finite Element Method and Transfer Matrix Method) are applied to analyze a circular tank on elastic foundation. By the given analysis methods, BEF analogy and foundation matrix method, the circular tank was transformed into the skeletonized frame structure. The frame structure was divided into several finite elements. The stiffness matrix of a finite element is related with the transfer matrix of the element. Thus, the transfer matrix of each finite element utilized the transfer matrix method to simplify the analysis of the tank. There were no significant difference in the results of two methods, the finite element method and the transfer matrix method. The transfer method applied to a circular tank on elastic foundation resulted in four simultaneous equations to solve completely.

  • PDF

Reconstruction of Vibroacoustic Field from the Measured Pressures Using the Boundary Element Method (경계요소법과 음장측정치에 의한 소음원의 진동장 및 음장 재구성)

  • 김봉기;이정권
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • /
    • pp.50-55
    • /
    • 1995
  • 진동하는 경계면의 진동장 및 음장을 재구성하기 위하여 음장측정치 및 경계요소법을 이용한 음향 홀로그래피 방법을 연구하였다. 특히, 측정잡음 및 전달행렬의 특이성에 의해 발생하는 재구성 오차에 대하여 고찰하였다. 재구성의 정확도를 나타내기 위하여 전달행렬의 특이인자를 도입하였다. 예제로 한면이 진동하는 직육면체 상자를 고려하였다. 결과로부터 매우 작은 측정잡음에 대해서도 전달행렬의 특이성 재구성 오차가 크게 발생하며, 측정위치에 따라 전달행렬의 특이성이 크게 영향 받음을 확인하였다. EfI방법을 이용하여 최적의 측정점을 선택한 결과 전달행렬의 특이성을 크게 줄일 수 있었으며 이때 측정점의 위치는 가진주파수에 관계없이 큰 음장이 형성되는 소음원의 근접장에 위치함을 알 수 있다. 또한 저주파 가진에 비해 고주파 가진이 작은 특이인자값을 나타내며, 따라서 재구성 오차가 작음을 알 수 있었다. 재구성장의 정밀도를 향상시키기 위하여, 부가적으로 진동장의 norm을 제한하는 적절화방법을 도입하였다. 모델의 최소자승오차를 최소화 하는 최적의 적절화변수를 추정하여 이로부터 재구성 오차를 줄일 수 있었다.

  • PDF

Static Aanlysis of Curved box Girder Bridge with Variable Cross Section by Transfer Matrix Method (전달행렬법에 의한 변단면 곡선 상자형 거더교의 정적해석)

  • Kim, Yong-Hee;Lee, Yoon-Young
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.7 no.4
    • /
    • pp.109-120
    • /
    • 2003
  • The state-of-art of curved box girder bridge with cross section design has advanced in various area. In these days, several analytical techniques for behaviors of curved box girder bridges cross section are available to engineers. The transfer matrix method is extensively used for the structural analysis because its merit in the theoretical background and applicability. The technique is attractive for implementation on a numerical solution by means of a computer program coded in Fortran language with a few elements. To demonstrate this fact, it gives good results which compare well with finite element method. Therefore, this paper proposed the static analysis method of curved box bridge with cross section by transfer matrix method based on pure-torsional theory and the optimal span ratio/variable cross section ratio of 3 span continuous curved box girder bridge.

Dynamic Analysis of Cracked Timoshenko Beams Using the Transfer Matrix Method (전달행렬법을 사용하여 균열이 있는 티모센코 보의 동특성 해석)

  • Kim, Jung Ho;Kwak, Jong Hoon;Lee, Jung Woo;Lee, Jung Youn
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.26 no.2
    • /
    • pp.179-186
    • /
    • 2016
  • This paper presents a numerical method that can evaluate the effect of crack for the in-plane bending vibration of Timoshenko beam. The method is a transfer matrix method that the element transfer matrix is deduced from the element dynamic stiffness matrix. An edge crack is expressed as a rotational spring, and then is formulated as an independent transfer matrix. To demonstrate the accuracy of this theory, the results computed from the present are compared with those obtained from the commercial finite element analysis program. Based on these comparison results, a parametric study is performed to analyze the effects for the size and locations of crack.

Numerical Analysis for Modeling of Sound Absorbing Medium using Transmission Line Matrix Modeling (전달선로행렬법을 이용한 흡음재 모델링에 대한 수치해석)

  • Park, Kyu-Chil;Yoon, Jong-Rak
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.16 no.8
    • /
    • pp.1599-1605
    • /
    • 2012
  • We introduced an approach of modeling of a sound absorbing medium that had different absorbing coefficient according to frequency. To obtain the time domain result of the frequency characteristics of a sound absorbing medium, transmission line matrix modeling was used. To input sound absorbing effect in TLM modeling, we added a FIR filter at a node instead of absorbing component using resistance component. There were simulated the characteristics of time-shift, low pass filter, high pass filter using the FIR filter with 7-tap coefficients, then compared with theoretical results. From various simulation results, we could find that added FIR filter coefficient in TLM modeling was an useful way to model a sound absorbing medium.

On the Reconstruction of Vibrating Source by using the Nearfield Acoustic Holography based on the Nonsingular BEM (특이성의 제거된 경계요소법에 기초한 음향 홀로그래피에 의한 음원 진동장 재구성에 관하여)

  • 강승천
    • Proceedings of the Acoustical Society of Korea Conference
    • /
    • /
    • pp.313-317
    • /
    • 1998
  • 경계요소법에 기초한 음향 홀로그래피의 재구성 정확도 향상을 위해서는 근접 음장에서의 음압 측정을 수반한다. 이에 따라 비전파음 성분이 측정에 포함되어 전달행렬의 특이성에 의한 오차를 줄일 수 있다. 그러나, 전달행렬 구성을 위해서 사용되는 일반적인 경계요소법은 Kirchhoff-Helmholtz 방정식의 기본해가 갖는 특이성 때문에 근접음장에서 큰 수치 오차를 유발하는 문제가 있다. 특이성이 제거된 경계 적분방정식을 도입하여 음향 홀로그래피를 수행함으로써 근접 음장에서의 수치오차 문제를 극복하고 정확한 음장 예측 및 전달 행렬을 구성할 수 있다. 본 연구에서는 단순한 수치 해석 모델을 이용하여 음향 홀로그래피 계산을 수행하였고, 일반 경계요소법을 사용한 경우와 비교하여 향상된 결과를 얻을 수 있음을 밝혔다.

  • PDF

A Simple Analysis of the Cylindrical Shell Subjected to a Nonaxisymmetric Load (비축대칭 하중을 받는 원통형 쉘의 단순화 해석)

  • 남문희;이관희
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.13 no.2
    • /
    • pp.179-187
    • /
    • 2000
  • When one considers the property of the axisymmetry, an analysis of an axisymmetric shell subjected to unaxisymmetric loading can be employed to save time and computer memory space. If one considers the Fourier series of the circumference direction of loads and displacements, an axisymmetric tank subjected to a nonaxisymmetric load can be treated as a frame element. Using the Fourier series, the authors derived the stiffness matrix of the cylindrical shell subjected to unaxisymmetric loading by the usual finite element method, and converted the stiffness matrix of a frame element into a transfer matrix by rearranging the stiffness matrix to apply the transfer matrix method. Here the most significant purpose of this paper is to achieve the fewest number of simultaneous equations for analysing an axisymmetric shell subjected to a nonaxisymmetric load. The results of the proposed method of the analysis of the cylindrical shell subjected to a wind load and a water load show no differences when compared to the other methods.

  • PDF

Vibration Analysis of Three-Dimensional Piping System by Transfer Matrix Method (전달행렬법을 이용한 3차원 파이프 계의 진동해석)

  • 이동명
    • Journal of The Korean Society of Manufacturing Technology Engineers
    • /
    • v.7 no.6
    • /
    • pp.110-116
    • /
    • 1998
  • For the vibration analysis of 3-dimensional piping system containing fluid flow, a transfer matrix method is presented. The fluid velocity and pressure were considered, that coupled to longitudinal and flexural vibrations. Transfer matrices and point matrices were derived from direct solutions of the differential equations of motion of pipe conveying fluids, and the variations of natural frequency with flow velocity for 3-dimensional piping system were investigated.

  • PDF