• Advances in Computational Design
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• 제2권4호
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• pp.257-271
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• 2017

There are many plain concrete arch bridges in Iran that have been used as railway bridges for more than seventy years. Owe to the fact that these bridges have not been designed seismically, and even may be loaded under high-speed trains, evaluation of fundamental frequencies of the bridges against earthquake and high-speed train vibrations is necessary for considering dynamics effects. To evaluate complex behavior of these bridges, results of field tests are useful. Since it is not possible to perform field tests for all arch bridges, these structures should be simulated correctly by computers for structural assessment. Several parameters are employed to describe the bridges, such as number of spans, length of spans, geometrical and material properties. In this study, results of field tests are used for modal analysis and adapted for 64 three dimensional finite element models with various physical parameters. Computer simulations show length of spans has important effect on fundamental frequencies of plain concrete arch bridge and modal deformations of bridges is in longitudinal and transverse directions. Also, these results demonstrate that fundamental frequencies of bridges decrease after increasing span length and number of spans. Plus, some relations based in the number of spans (n) and span length (l) are proposed for calculation of fundamental frequencies of plain concrete arch bridge.

• 복합신소재구조학회 논문집
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• 제6권4호
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• pp.1-7
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• 2015

In this paper, we present the result of analytical investigation pertaining to the structural behavior of steel-concrete composite plate girder with arch-type web stiffener. In the arch-type web stiffener located in the compression side of web, infill concrete is cast to strengthen the arch-type stiffener and also to exert resisting force against compression force. This type of composite steel-concrete plate girder bridge is built and is in service. To understand the behavior thoroughly, analytical parametric study was conducted by using the finite element method. As a result it was found that the effect of arch-type stiffener with infill concrete is considerable for the design of such type composite girder bridge.

• 한국전산구조공학회논문집
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• 제23권3호
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• pp.247-254
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• 2010

유리섬유강화 폴리에스터(GFRP) 복합소재는 가볍고 내구성이 뛰어나 강재, 콘크리트, 나무 등과 같은 기존의 구조 재료들을 대체할 수 있는 재료로 최근 각광 받고 있다. 이러한 복합소재를 활용하기 위해 쉽게 조립할 수 있는 수직결구식 복합소재 데크를 활용한 아치가교 유형을 선행 연구에서 제안하였고 유한요소해석을 통해 검증하였다. 이 논문에서는 선행연구에서 제안된 볼트결합에 의한 복합소재 데크 조립식 아치가교의 안전성 및 사용성을 구조성능시험을 통해 검증하여 문제점을 파악하고 그 문제점을 해결하기 위해 개선된 아치가교 유형을 제안한다.

• Smart Structures and Systems
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• 제17권6호
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• pp.1107-1127
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• 2016

Studies on dynamic characteristics of the hanger vibration using field monitoring data are important for the design and evaluation of high-speed railway truss arch bridges. This paper presents an analysis of the hanger's dynamic displacement responses based on field monitoring of Dashengguan Yangtze River Bridge, which is a high-speed railway truss arch bridge with the longest span throughout the world. The three vibration parameters, i.e., dynamic displacement amplitude, dynamic load factor and vibration amplitude, are selected to investigate the hanger's vibration characteristics in each railway load case including the probability statistical characteristics and coupled vibration characteristics. The influences of carriageway and carriage number on the hanger's vibration characteristics are further investigated. The results indicate that: (1) All the eight railway load cases can be successfully identified according to the relationship of responses from strain sensors and accelerometers in the structural health monitoring system. (2) The hanger's three vibration parameters in each load case in the longitudinal and transverse directions have obvious probabilistic characteristics. However, they fall into different distribution functions. (3) There is good correlation between the hanger's longitudinal/transverse dynamic displacement and the main girder's transverse dynamic displacement in each load case, and their relationships are shown in the hysteresis curves. (4) Influences of the carriageway and carriage number on the hanger's three parameters are different in both longitudinal and transverse directions; while the influence on any of the three parameters presents an obvious statistical trend. The present paper lays a good foundation for the further analysis of train-induced hanger vibration and control.

• 농촌계획
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• 제22권3호
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• pp.63-70
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• 2016

Due to the Korea's topographic characteristic, there are a lot of marine bridges to connect between islands and mainland. In addition, marine bridges play an important role in a regional landscape. For these reasons, landscape design of bridge is necessary in order to improve beautification of region. So, this studies analyzed image and landscape preference of marine bridges in rural area. The main results were summarized as follows: When rating the image of the background in sea and mountain image, 'stable' and 'natural' were rated highly. When rating the image of the arch bridge in sea and mountain image, 'beautiful', and 'attractive' were rated highly. When rating the image of the cable-stayed bridge in sea and mountain image, 'splendid', and 'attractive' were rated highly. When rating the image of the suspension bridge in sea and mountain image, 'beautiful', and 'splendid' were rated highly. Next, When rating the image of the background in sea and building image, 'stable' and 'natural' were rated highly. When rating the image of the arch bridge in sea and building image, 'beautiful', and 'splendid' were rated highly. When rating the image of the cable-stayed bridge in sea and building image, 'beautiful', and 'attractive' were rated highly. When rating the image of the suspension bridge in sea and building image, 'beautiful', and 'attractive' were rated highly. And, The image of suspension bridges in sea and mountain image is more highly preferred than other image. The background in sea and mountain image is landscape of the lowest preference. In the mountain and sea image, the preference of suspension bridge landscape has the highest rating. In the sea and building image, the preference of arch bridge landscape has the highest rating. In conclusion, the results illustrate that the marine bridge's shape and its background in rural area are important elements of a visual preference. When designing the marine bridge, designer have to choose a proper bridge shape for its background. However, this research's limitation is that this research consider only bridge shape and background to analyze landscape preference of marine bridges. Therefore, further research is necessary to consider various elements.

• 콘크리트학회논문집
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• 제29권4호
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• pp.371-378
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• 2017

본 연구에서는 철근콘크리트 아치 데크의 정적재하실험을 통해 휨 거동을 평가하였다. 휨 실험은 길이 2.5 m, 폭 1.2 m, 중심단면 두께 100 mm, 단부단면 두께 160 mm의 실제 크기 프리캐스트 철근콘크리트 아치 데크의 정적재하 실험을 실시하였다. 실험결과는 극한설계강도에 비하여 약 1.74배 높은 하중을 견디는 것으로 관찰되었다. 반면, 실험체에는 구간에 따라 각각 다른 거동이 관찰되었다. 이러한 거동은 아치 데크와 이를 지지하는 반력대 사이에 일체거동이 이뤄지지 않은 이유로 인한 것으로 판단되었다. 그러므로 추후 연구에서는 반력대를 제외한 아치 데크의 정적재하 실험을 통해 정밀한 거동을 확인해야 할 것으로 사료된다. 실험결과를 종합하여 보면, 철근콘크리트 아치 데크는 일반형태의 바닥판에 비하여 우수한 구조적 이점을 통해 설계기준보다 높은 구조성능을 나타내었다. 이를 통해, 향후에는 장지간 바닥판으로써의 활용이 가능할 것으로 사료된다.

• 한국산학기술학회논문지
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• 제15권11호
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• pp.6898-6905
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• 2014

스트레스 리본 교량(Stress Ribbon Bridge)이란 두께가 얇은 상부구조(바닥판)가 특정한 현수 형태(catenary type)로 유지되고 긴장된 바닥판 (Post-tensioned deck)이 하중에 의해 역 아치(Reverse arch) 거동을 보이는 PSC 구조물이다. 현재 스트레스 리본 교량의 경우 국외에서 자연파괴를 최소화 하고 아름다운 구조로 인식되어 차도교, 보도교 등에 활발하게 이용되고 있으나 국내에서는 이와 관련된 연구가 매우 미흡한 실정이다. 본 연구에서 시공단계가 고려된 스트레스 리본교량의 비선형, 시간의존적 해석이 고려된 모델을 정립하는데 목표가 있다. 정립된 모델을 이용하여 시공단계에 따른 단면력을 이론에 의한 수치와 비교하여 그 타당성을 입증하였으며, 시공단계에 따른 교량의 거동을 분석하였다.

• Earthquakes and Structures
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• 제10권2호
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• pp.483-494
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• 2016

Historical structures that function as a bridge from past to present are the cultural and social reflections of societies. Masonry bridges are one of the important historical structures. These bridges are vulnerable against to seismic action. In this study, linear and non-linear dynamic analyses of historical Nadir Bridge are assessed. The bridge is modelled with three dimensional finite elements. For the seismic effect, artificial acceleration records are generated considering the seismic characteristics of the region where the bridge is located. Seismic response of the bridge is investigated.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 지반공학 공동 학술발표회
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• pp.613-620
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• 2005

This research is experimental paper to prepare the structural safety of the upper bridge for support type on tunnel and the effect of settlement. Unit weight test and uni-axial compression test have been performed to simulate the physical property of foundation on the tunnel. Tunnel model of slip form type for centrifuge model has been developed to performed the tunnel excavation while field stress is activated. And the support type of tunnel such as umbrella arch method and large diameter steel pipe reinforce method has been tested for the centrifuge model. After the analysis of experiment, results show that internal displacement of large diameter steel pipe reinforce method is smaller than that of the umbrella arch method.

• Earthquakes and Structures
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• 제2권2호
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• pp.189-206
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• 2011

In this study, the subspace stochastic realization theories (SSR model I and SSR model II) have been applied to a real bridge for estimating its dynamic characteristics (natural frequencies, damping constants, and vibration modes) under ambient vibration. A numerical simulation is carried out for an arch-type steel truss bridge using a white noise excitation. The estimates obtained from this simulation are compared with those obtained from the Finite Element (FE) analysis, demonstrating good agreement and clarifying the excellent performance of this method in estimating the structural dynamic characteristics. Subsequently, these methods are applied to the vibration induced by both strong and weak winds as obtained by remote monitoring of the Kabashima bridge (an arch-type steel truss bridge of length 136 m, and situated in Nagasaki city). The results obtained with this experimental data reveal that more accurate estimates are obtained when strong wind vibration data is used. In contrast, the vibration data obtained from weak wind provides accurate estimates at lower frequencies, and inaccurate accuracy for higher modes of vibration that do not get excited by the wind of lower intensity. On the basis of the identified results obtained using both simulated data and monitored data from a real bridge, it is determined that the SSR model II realizes more accurate results than the SSR model I. In general, the approach investigated in this study is found to provide acceptable estimates of the dynamic characteristics of highway bridges as well as for the vibration monitoring of bridges.