• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.3A
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• pp.235-241
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• 2009

PSC girder bridge is known to be more economical than other types of bridges and has been usually applied to a span range of 25 m to 35 m according to the standard shapes for highway bridges in Korea. The spans of the recently developed new types of PSC girders are also limited to 50 m at most. In this study, therefore, feasibility of the long-span PSC girder that reaches more than 50 m is investigated by applying several strategies from the perspectives of materials, design and construction. A systematic procedure is proposed that can be used to assess the effect of each strategy on the span. The proposed scheme adopts a graphical approach that represents a relationship between the number of prestressing tendons and the span, and is derived on a basis of safety assessment equations of the girder in each stage of fabrication and in service. In the companion paper, the amount of span extension is quantitatively evaluated by applying the proposed scheme into a sample PSC girder bridge.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.2
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• pp.389-402
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• 2014

In this paper, the load test of full-scale precast concrete arch bridges considering reinforced joint and backfill was conducted. It is an improved method that the reinforced joint enhanced the structural performance of conventional masonry arch system which was proposed by previous researchers. The models of full-scale test are $10m(span){\times}3m$ (rise) and $10m(span){\times}2m$ (rise), which are 2 meters in width. The critical load position was shown at a third-span from the results of the pre-analysis. Based on the this results, the positions of load, measuring items and points were determined in experiments. As a result, the maximum load capacity of the specimen $10m{\times}2m$, a relatively small rise to span ratio (compared to the specimen $10m{\times}3m$), was higher than the specimen $10m{\times}3m$. It was evaluated that all the specimens have sufficient structural performance on the design load.

• Journal of Korean Society of Steel Construction
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• v.17 no.3 s.76
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• pp.317-324
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• 2005

The specially orthotropic plate theory is used to analyse three-span continuous composite slab bridges with elastic intermediate supports. A method of calculating the natural frequency corresponding to the first mode of vibration of beams and tower structures, with irregular cross sections and with arbitrary boundary conditions, was developed and the result of application of this method to the three-span continuous composite slab bridges with elastic intermediate supports is presented. This type of bridge represents either concrete or sandwich type three-span bridge on polymeric supports for passive control or on actuators for active control. Any method may be used to obtain the deflection influence surfaces needed for this vibration analysis. The finite difference method is used for this purpose in this paper. The influence of flexural stiffnesses and the modulus of the foundation are studied.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.3
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• pp.97-102
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• 2018

Conventional PSC I type girders were adversely affected by the self - weight of concrete, anchorage, prestressing. In order to overcome this problem, PSC girder was constructed with a hollow in the web and developed a hollow web PSC type I girder which is applicable to 50 - 70m span by multistage stressing and then actually long span hollow web PSC girder bridge was constructed. In this study, the results of Static Load Test and the Finite Element Analysis of the hollow web PSC I girder bridges were compared and analyzed, and the Load Carrying Capacity and safety of PSC girder bridges were evaluated. The Static Load Test and the numerical analysis results of this bridge showed similar tendency and the behavior of the hollow web PSC I girder was well simulated. The entire girders of the bridges had sufficient Load Carrying Capacity under the live load design condition and the bridges satisfied the safety and confirmed the appropriateness of the construction.

• Magazine of the Korea Concrete Institute
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• v.20 no.3
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• pp.34-39
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• 2008

• Journal of Navigation and Port Research
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• v.32 no.10
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• pp.743-750
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• 2008

Recently Bridges crossing waterway are constructed in navigable waterway, so marine accidents near bridges navigable waterway often occurred bemuse that has affect dangerous element for. This paper analysed the necessary environmental factors to navigate safely near bridges and how to set up the environmental factors. Marine accidents elements occurred near bridges relate to span of bridge, size of navigating ship, length of straight way and traffic volume except mistake of mariners. As results of marine accident parameter analysis, Span of bridge is necessary more than 300m at least based on marine accident's analysis, and in case of more than ship's Length 150m, span of bridge is necessary more than 500m, $3{\sim}4L$(L; Ship's Length). Length of straight way before bridge is necessary more than 8L to minimize the marine accident.

• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.6
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• pp.102-110
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• 2023

PSC-I girder bridges constitute the largest proportion among highway bridges in Korea. According to the precision safety diagnosis data for the past 10 years, approximately 41.3% of the PSC-I bridges have been graded as C. Furthermore, with the increase in the aging of bridges, preemptive management is becoming more important. Damage and deterioration to the deck and girder with a long replacement cylce can have considerable impacts on the service and deterioration of a bridge. In addition, the high rate of device damages, including expansion joints and bearings, necessitates an investigation into the influence of the device damage in the structural members of the bridge. Therefore, this study defined representative PSC-I girder bridges with single and multiple spans to evaluate heterogeneous damages that incorporate the damage of the bridge member and device with the deterioration of the deck. The heterogeneous damages increased a crack area ratio compared to the individual single damage. For the single-span bridge, the occurrence of bearing damage leads to the spread of crack distribution in the girder, and in the case of multi-span bridges, expansion joint damage leads to the spread of crack distribution in the deck. The research underscores that bridge devices, when damaged, can cause subsequent secondary damage due to improper repair and replacement, which emphasizes the need for continuous observation and responsive action to the damages of the main devices.

• Proceedings of the KSR Conference
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• 2002.05a
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• pp.177.1-182
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• 2002

본 연구는 합성교량의 경우 브라켓이나 가로보에 사용되고 비합성교량의 경우 연결재로 사용되는 스랩앵커를 Push-Out Test를 하여 실험으로 얻은 특성을 실제 소수주형모델에 적용하여 FEM해석을 통하여 거동특성을 파악 하고자 한다. 일반적으로 전단연결재 실험의 경우 콘크리트 슬래브와 강재 주형 사이에 직접 길이 방향 전단력을 작용시킬 수 있을 뿐 아니라 실험의 편리함 때문에 주로 Push-out 실험이 많이 이용되고 있다. 본 실험에서는 BS-5400에 제시된 바에 근거하여 실험체를 제작하였다. 이 실험을 통하여 탄성구간에서의 강성(k) 값을 알아내어 3D FEM 해석에 적용한다. 이때 콘크리트 바닥판과 강재와의 연결을 축 방향으로는 특정한 강성 값을 넣을 수 있는 Joint Element를 사용하여 연결시키고, 1경간 단순지지와 2경간 연속교에 대하여 연구를 수행하는데, 1경간 단순지지의 경우에는 Joint Element에 여러 강성 값과 실험을 통해 얻은 강성 값을 적용하여 합성거동을 파악하고 강성 값에 따른 합성정도를 규명하고자 한다. 또한 2경간 연속교에서는 슬랩앵커의 강성 값을 적용하여 많이 문제시되고 있는 내부지점부에 슬랩앵커를 사용하였을 때 슬래브의 인장응력이 어떤 변화양상을 나타내는지 파악 하고자한다.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.5
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• pp.87-95
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• 2014

Cable stayed bridge is supported by cables and the negative reaction occurs by cables at anchor pier. To solve this problem, the proper side span ratio and the negative reaction measure of anchor pier are needed. And structural system of cable stayed bridge is determined by solution of the negative reaction as installation of the intermediate pier, counterweight and so on. In feasibility study, Vam Cong bridge was planned as 5 span cable stayed bridge. However, it was changed to 3 span cable stayed bridge in detailed design because of constructability and economy. The intermediate pier was excluded in order to improve the constructability, and side span ratio increased to control the negative reaction. As a result, Vam Cong bridge secure constructability, structural safety, and efficiency.

• Journal of the Earthquake Engineering Society of Korea
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• v.8 no.4
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• pp.21-32
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• 2004

A Seismic analysis procedure of bi-directional brideg motions is developed by using mechanical bridge model. A three-dimensional mechanical model can consider major phenomena under bi-directional seismic excitations, such as nonlinear pier motion under biaxial bending, pounding and bearing damage due to the rotaion of the superstructure, etc. The analyses utilizing the uni-directional and the bi-directional bridge model for the 3-span simply supported bridge are then performed. The seismic responses in two cases are examined and compared by investigating the relative displacements of each superstructure to both ground and adjacent superstructures and the restoring forces of RC pier. The analysis using either the uni-directional model or bi-directional model is acceptable for estimating the displacement responses of a bridge, but the bi-directional analysis is found to give more conservative results for resisting forces of RC piers. To make general conclusions, therefore, the analysis using the bi-directional bridge model should be performed in evaluating the seismic safety of bridges.