• 한국철도학회:학술대회논문집
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• 한국철도학회 2006년도 추계학술대회 논문집
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• pp.530-537
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• 2006

Recently, the railroad route plan is trying to minimize the damage of the local resident which is caused by railroad construction. For this reason, reducing the banking height of soil roadbed, lowering the bridge girder height of a solid intersection and a part of cross river, the through bridge type which can achieve a required span length must apply. The representative through bridges of railroad are arch bridges, truss bridges and plate girder bridges, the through plate girder bridge of variable section can apply that the span length of these bridges is about $30{\sim}50m$, namely, middle span length bridge types, and that can satisfy structural capacity and beauty of railroad at the same time. This paper introduces plan and design process of the Su-eo cheon bridge applied by a through plate girder bridge type of the Jinju-Gwangyang double track 6th construction ordered at Korea Rail network Authority in 2005.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 1999년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Fall
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• pp.251-258
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• 1999

The vibration control of bridge is studied considering the vibration characteristics of the Korean-type high-speed railway bridge. Fast nonlinear analysis is adopted as time integration method and the bridge and the train are modeled by FEM and sequentially moving constant forces respectively. Additional damping mechanism is indispensable to the Korean-type high-speed railway bridge because resonance vibration is excited under the maximum design speed. The optimal position and capacity of the damper is studied through the parametric studies, Transient vibration of the bridge is effectively controlled by such additional dampers which means that dampers play a role as structural damping. And also the maximum response of the bridge is reduced. Therefore it is verified that the increase of expected service life and the improvement of serviceability can be obtained through dampers.

• EDISON SW 활용 경진대회 논문집
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• 제4회(2015년)
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• pp.251-256
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• 2015

In this paper, an systematic approach is presented, in which the bridge-type traffic sign structure is body out by CSDDA PrePost Processor. There is dead load and wind load that is working on the structure which will make force and moment. Analyzied the stress distribution of the standard form and by changing the shape, compared the safety in terms of deflection and stress (with the standard form) to know the effect of each component in the bridge-type traffic sign structure. The safety of deflection and stress is evaluated by maximum distance/100) and ASIC code respectively. The standard form of bridge-type traffic sign structure is established by two pairs of pillar and two pairs of floor beam. Replaced the links which is consist of flange and screws as the torsion spring and nm our analysis program. By adjusting variable of rigidity modulus of torsion spring, moment between column and beam is controled depending on value of rigidity modulus.

• Structural Engineering and Mechanics
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• 제11권1호
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• pp.35-48
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• 2001

The objective of this study is to investigate the stability behavior of steel cable-stayed bridges by comparing the buckling loads obtained by means of finite element methods with eigen-solver. In recent days, cable-stayed bridges dramatically attract engineers' attention due to their structural characteristics and aesthetics. They require a number of design parameters and present a high degree of static indetermination, especially for long span bridges. Cable-stayed bridges exhibit several nonlinear behaviors concurrently under normal design loads due to the individual nonlinearity of substructures such as the pylons, stay cables, and bridge deck, and their interactions. The geometric nonlinearities arise mainly from large displacements of cables. Strong axial and lateral forces acting on the bridge deck and pylons cause structural nonlinear behaviors. The interaction is among the substructures. In this paper, a typical three-span steel cable-stayed bridge with a variety of design parameters has been investigated. The numerical results indicate that the design parameters such as the ratio of $L_1/L$ and $I_p/I_b$ are important for the structural behavior, where $L_1$ is the main span length, L is the total span length of the bridge, $I_p$ is the moment of inertia of the pylon, and $I_b$ is the moment of inertia of the bridge deck. When the ratio $I_p/I_b$ increases, the critical load decreases due to the lack of interaction among substructures. Cable arrangements and the height of pylon are another important factors for this type of bridge in buckling analysis. According to numerical results, the bridges supported by a pylon with harp-type cable arrangement have higher critical loads than the bridges supported by a pylon with fan-type cable arrangement. On contrary, the shape of the pylon does not significantly affect the critical load of this type of bridge. All numerical results have been non-dimensionalized and presented in both tabular and graphical forms.

• 한국방재학회 논문집
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• 제4권1호
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• pp.15-24
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• 2004

일반적으로, 2개의 I형 거더로 이루어진 ${\pi}$형거더는 공기역학적으로 불안하여 내풍설계에 있어 매우 불리 한 것으로 알려져 있다. 공기역학적 진동은 구조물의 강성이나 감쇠의 향상, 단면 형상의 연구 등에 의해 억제될 수 있으므로 본 연구에서는 ${\pi}$ 형단면을 가진 4경간 사장교에 대해 영각과 공기역학적 제진장치의 추가로 인한 단면의 변화에 따른 2차원 진동실험을 통하여 공기역학적 특성을 파악하도록 하였다. 등류와 난류에서의 실험결과 본 교량단면은 기본단면만으로도 내풍안정성을 충분히 갖추고 있기 때문에 페어링(Fairing) 및 베플(Baffle Plate) 등의 추가적인 공기역학적 제진장치가 필요하지 않을 것으로 판단된다. 이는 본 교량의 경우 주경간이 230m인 4경간으로 이루어져 있어 비슷한 단면을 가진 교량에 비하여 수직 및 비틀림 진동수가 크고 강성이 크기 때문에 설계풍속 내에서 공기역학적으로 안정한 것으로 보여진다.

• 대한족부족관절학회지
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• 제20권2호
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• pp.73-77
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• 2016

Purpose: The purpose of this study was to evaluate the clinical outcome of a modified Kidner procedure using a suture bridge technique in symptomatic type II accessory navicular. Materials and Methods: Between January 2013 and December 2014, a total of 35 cases with symptomatic type II accessory navicular were treated with a modified Kidner procedure using the suture bridge technique. The patients were evaluated preoperatively, 3 months after surgery, and at the latest follow-up (at least six months postoperatively) clinically via the American Orthopaedic Foot and Ankle Society (AOFAS) midfoot score, visual analogue scale (VAS), and the self-subjective satisfaction score. Results: The mean AOFAS midfoot score demonstrated significant improvement from a mean of 45.3 preoperatively to a mean of 89.2 at 3 months after surgery. At the latest follow-up, the mean AOFAS midfoot score was 92.6 (p<0.001). The mean VAS also improved significantly, decreasing from 6.7 out of 10 preoperatively to 1.8 at 3 months after surgery. At the latest follow-up, the VAS was 1.2 (p<0.001). The mean time of a single-limb heel raise was 4.6 months postoperatively and the self-subjective satisfaction score was 1.4 out of 4 at the latest follow-up. Conclusion: The short-term surgical results of the modified Kidner procedure with a suture bridge technique for symptomatic type II accessory navicular were good to excellent in terms of pain, functional and clinical assessments. In conclusion, the modified Kidner procedure with the suture bridge technique is a reasonable treatment option for symptomatic type II accessory navicular.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2000년도 봄 학술발표회논문집
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• pp.246-252
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• 2000

The nonlinearity of a cable-stayed bridge results in the large displacement of main girder due to a long span, the large axial forces reduce the catenary action of cables and the flexural stiffness. Therefore, the static and dynamic behavior of pylon for a cable-stayed bridge plays an important role in determining its safety. This study was performed to find the behavior of pylon of cable-stayed bridge for the first-order analysis considering of axial load only and for the second-order analysis considering of lateral deflection due to axial load. The axial force and moment values of pylon were different from the results of the first-order analysis and second-order analysis according to pylon shape and cross beam stiffness when the pylon was subjected to earthquake and wind loads. In the second-order analysis, comparing the numerical values of the member forces for the dynamic analysis, types 3 and 4 (A type) were relatively more advantageons types than types 1 and 2 (H type). Considering the stability for pylon of cable-stayed bridge (whole structural system), types 3 and 4 (A type) with pre-buckling of girder were proper types than types 1 and 2 (H type) with buckling of pylon.

• Architectural research
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• 제7권2호
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• pp.81-89
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• 2005

Over the years, existing bridges have had various degrees of maintenance to extend the service life. As the existing bridges continue to deteriorate, however, each Department of Transportation (DOT) of the United States of America faces increasing demands on the limited funds available for bridge maintenance. Therefore, it is very important for State Department of Transportations to establish Maintenance, Repair, and Rehabilitation (MR&R) strategies for bridge structures such that funds get allocated for appropriate maintenance over the service life. This paper identifies the state-of-art and the state-of-practice of MR&R actions and the use of MR&R strategies in concrete bridge decks. In addition, a questionnaire survey was conducted to identify the type and timing for MR&R actions as well as existing MR&R strategies taken in concrete bridge deck by each DOT. This paper also presents the results of the survey.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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• pp.615-620
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• 2001

The aim of this paper is to open up a relatively new type in bridge engineering by introducing plan and design of extradosed bridge which is implemented in Sungnam-Janghowon T/K project. The topic encompasses parametric study including the behavior of the bridge relevant to the cable layout, the distance from pier table to the first cable's location, the height of pylon, the stiffness of cross section and wind vibration to ascertain sectional type of bridge and span length. For the purpose of the knowledge base presented here, the important feature of design is recommended such as modeling method, camber control, finite element analysis and heat hydration of pier table. We can verify the issue related to the characteristics of extradosed bridge as a result of study and design endeavor.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2007년도 추계학술대회 및 제23회 정기총회
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• pp.376-382
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• 2007

항로를 횡단하여 건설된 교량은 부근을 지나던 선박의 기관이나 조타기의 고장 또는 비상한 외력의 영향이나 인위적인 판단오류로 인하여 발생할 수 있는 선박과 교각의 충돌을 예방하고 불가피한 충돌의 경우에도 교량의 붕괴를 방지하는 대책을 마련하여야 한다. 충돌이나 간접 충격에 의하여 교량의 상판이 붕괴되는 경우 많은 인명의 손실과 교량으로 연결되는 간선도로의 장기간 폐쇄는 국가적인 재앙이 될 것이기 때문이다.