1축 대칭단면을 갖는 곡선교의 고유진동수특성

임성순,Yhim, Sung Soon 대한토목학회 1994 대한토목학회논문집 Vol.14 No.6

평면에서 곡선을 이루는 들보는 흔히 뒬효과를 고려한 원형곡선부재로 설계된다. 본 연구에서는 곡선교를 단면이 일축대칭이고 단순지지된 원형곡선부재로 이상화시켰다. 경계조건을 만족하는 변위형상함수를 퓨리어급수로 전개하고 이로부터 곡선교의 전동수방정식을 유도하였다. 곡선형교의 특성을 나타낼 수 있는 매개변수-중심각, 곡률계수 및 단면의 대칭성계수-의 변화에 따른 원형곡선부재의 고유진동수 특성분포를 보였다. 몇 개의 해석예를 통하여 고유진동수에 미치는 매개변수의 효과를 조사하였다. Beams curved in plan are often designed with the circular curved member system including warping effects. In this study, the curved bridges are idealized as the circular curved member system with singly symmetric cross sections and simply supported ends. Displacement fields of them to satisfy the boundary conditions are expanded by Fourier series and the governing equation of natural frequencies of them is derived. The distributions of the characteristics of natural frequencies of them are shown according to the variations of relevant parameters-angle of intersection, curvature, and parameter of symmetry of cross section which can represent the properties of the curved bridges. A parametric study is conducted to investigate the effect of relevant parameters on natural frequencies.

사장교의 케이블 초기장력 및 기준길이 결정에 관한 연구

임성순 한국구조물진단유지관리공학회 2005 한국구조물진단유지관리공학회 논문집 Vol.9 No.2

이동하중을 받는 직선형 거더교의 동적거동분석

임성순 서울시립대학교 산업기술연구소 1996 산업기술연구소논문집 Vol.4 No.-

This study presents the dynamic responses of the straight girder bridges subjected to moving load with constant speed. The bridges is considered to be a continuous system of constant cross sectional properties. An exact solution to the governing differential equation is obtained in the form of the transformed equation derived by Fourier sine integral transformation method and Laplace integral method. Some of main conclusions are that the mass of the moving loads is an important factor in determining the impact factor for displacements and bending moments, and that the speed of the moving load may play a primary role in the design of straight girder bridges in considering the dynamic effects.

연안정비 정책방향 -연안정비 기본계획 성과와 반성-

임성순 한국연안방재학회 2019 한국연안방재학회 학술발표대회 논문집 Vol.2019 No.1

주케이블의 슬라이딩을 고려한 현수교의 시공단계 해석

임성순,공민식,김병철 한국구조물진단유지관리공학회 2009 한국구조물진단유지관리공학회 논문집 Vol.13 No.3

현수교는 주케이블이 목표하는 형상을 이루어 기하학적 강성을 갖도록 앵커, 새들과 같은 장치를 적용하고 있다. 지금까지의 연구에서는 두 장치를 모두 고정절점으로 단순화하여 해석하는 것이 일반적이었다. 그러나 새들의 경우 주케이블의 슬라이딩 현상이 발생할 수 있으며 이로 인하여 구조물의 응답이 달라진다. 특히 현수교의 시공단계 초기에 셋백로프를 철거하거나 셋백을 수행하지 않는 경우 새들 전후 주케이블의 장력 차이가 커지므로 슬라이딩이 발생하기 쉽다. 따라서 본 연구는 유한요소법을 이용한 케이블의 슬라이딩 해석방법을 제시하고 슬라이딩을 고려한 현수교의 시공단계별 해석을 수행하여 슬라이딩을 고려하지 않은 해석결과와 차이를 분석하였다. 슬라이딩을 고려한 해석을 통해 얻어진 결과는 구조물에 불리한 응답을 나타낼 수 있으므로 주케이블과 새들 사이의 슬라이딩을 고려한 해석은 필수적이다. 또한 본 연구의 슬라이딩 해석방법 및 해석결과는 이후 현수교의 설계와 시공시의 참고자료로 활용될 수 있다. Anchors and saddles are used to have sufficient geometrical rigidity and make target configuration of main cable of suspension bridge. Neglecting the sliding effect at saddles, points at them have been idealized as fixed nodes in lots of former studies. In general, sliding effects are reported to show significant structural behaviors of main cable and cause to the different responses of bridges. During early erection steps of the suspension bridge, especially, the sliding effect occurs easily because there is large difference of cable tension between main and side span in removing set-back ropes or not applying set-back. This study presents the finite element analysis considering to cable sliding effect and shows the comparison of differences between sliding and non-sliding at election sequence. The analysis of sliding between main cables and saddles needs to obtain more realistic responses because the analysis result can represent unfavorably different responses of bridges. Moreover, the sliding analysis method and results in this study can be used to basic criteria in engineering design and construction steps.

장대 아치교 행어 파단에 의한 동적 해석

임성순,공민식,유이슬 한국구조물진단유지관리공학회 2010 한국구조물진단유지관리공학회 논문집 Vol.14 No.2

장대 아치교 설계 시 시공단계와 완성단계에서 발생할 수 있는 문제에 대하여 검토하고 있으나 케이블 손상에 대한 구조안전성 평가는 매우 미흡한 실정이다. 따라서 본 연구는 공용 중 충돌사고로 인한 행어 파단 시 교량의 구조안전성을 분석하는 것을 연구 목적으로 한다. 이를 위하여 행어 파단에 따른 하중을 충격함수로 이상화하여 동적 해석을 수행하였다. 행어가 파단 되었을 경우 각 행어의 최대 장력은 파단 된 행어와 인접한 행어에서 발생한 것으로 나타났으며 정적 하중보다 동적 하중에서 크게 나타났다. 그러므로 장대 아치교의 구조안전성을 확보하기 위해 행어 파단에 따른 충격하중을 동적 하중으로 고려한 해석이 필요하다. 또한 본 연구의 해석 방법 및 결과는 이후 아치교 설계 시 참고자료로 활용될 수 있다. Recently, various evaluations concerning structural stability under construction step and completely constructed step have been executed during a Long-span Arch Bridge designing procedure. However, the breakage of cable-hangers of arched bridge in unexpected accident or periodic cable-replacement has not been considered. Therefore, the purpose of this study is that analyzing structural safety of arched bridge when the cable-hangers being fractured by that reasons. Dynamic analysis are performed by idealizing impact load to three types of impact functions as fracturing the cables. Consequently, when the hangers are fractured, the maximum tensile force by dynamic analysis is larger than those by static analysis. Therefore, the dynamic analysis is demanded to accurately obtain the responses for the structural stability with a realistic impact loading model in the breakage and replacement of cable hangers of long-span arched bride. Moreover, the analysis method and results in this study can be used to basic criteria in design.

지진하중에 의한 사장교의 비선형 동적 응답

임성순 서울시립대학교 도시과학연구원 2001 도시과학논총 Vol.27 No.1

Cable-supported bridges consist of cables with high flexibility and girders with good stiffness. Typical models among these bridges are cable-stayed bridges and suspended bridges. In general, structural system composed of members with different strength presents very complex responses. Because cables with low stiffness cause geometrical non-linearity and entire structure shows up the non-linearity. When it subjects to earthquake excitation especially, the responses of cable-supported bridges are very complex. In this paper, Olympic grand bridge, typical cable-stayed bridge on Han-river in Seoul, is used as analytical model and cable is idealized as nonlinear Ernst's cable element. This paper presents the distribution of nonlinear dynamic responses of cable-stayed bridges subject to earthquake excitation.

케이블댐퍼 감쇠성능의 수치해석적 연구

임성순 한국복합신소재구조학회 2015 복합신소재구조학회논문집 Vol.6 No.2

Compared with a strong axial rigidity due to large intial tension, cable has a weak laterally flexural rigidity. A variety of dynamic loads such as traffic loads and wind loads etc. cause the cables to vibrate significantly and affect the mechanical properties and the performance of cables. Therefore, vibration reduction design is an urgent task to control the vibration of cable-supported bridges. Because a various kind of dampers have shown to reduce the amplitude and duration time of vibration of cable from measured date in field test, damper can be considered that it is effective device significantly to reduce the amplitude and duration time in vibration of cable. Vibration characteristics of cable can change according to manufacturing method and type of established form, and damper has been designed according to distribution of natural frequencies and vibration modes. In this study, numerical analysis is used to show the reduction effects of vibrations and present the design of damper for vibration reduction of cable.

아치요소를 이용한 평면뼈대구조물의 기하학적 비선형해석

任性淳 서울시립대학교 산업기술연구소 1994 산업기술연구소논문집 Vol.2 No.-

Most of the general loads on frames will produce significant nonlinear responses. Most modern codes recommend that frames be designed to resist severe loading, dynamic loading as well as static one, through ductile action. And Large displacements may occur before this ductility is mobilized. To date, however, nonlinear analysis has not been simple and foolproof enough to gain significant acceptance by designers. This study presents the contributions made toward both objectives. In the area of nonlinear mechanics, one of the most comprehensive theories, the updated Lagrangian formulation, is first reviewed for two-dimensional plane framed structures. From this review a more physically meaningful and computationally efficient form of this method for nonlinear structural analysis is proposed. Secondly, the stiffness formulation of two-dimensional curved arch element based on differential geometry used to complete the computer program for nonlinear analysis of the plane framed structures. Numerical results are presented to demonstrate the efficiency and accuracy of the proposed element.

임의방향 보강재를 가지는 복합적층 보강판의 해석

임성순,장석윤,박대용 한국구조물진단유지관리공학회 2004 한국구조물진단유지관리공학회 논문집 Vol.8 No.2