RC Arch Deck Development and Performance Evaluation for Enhanced Deck Width

Dal?Hun Yang,Min?Jae Kwon,Gi?Ha Eom,Jang?Ho Jay Kim 한국콘크리트학회 2018 International Journal of Concrete Structures and M Vol.12 No.6

Due to extreme business competitions in bridge construction industries, the cost reduction became the most important issue in winning a contract bidding. The largest bridge construction cost saving can be obtained by using precasted construction method and by reducing required number of girders, columns, and decks in the bridge system. Therefore, an precasted arch deck system is proposed to widen the lateral span of the deck, which can result in reducing the number of required I-type PSC girders for construction cost saving. A usual lateral width of a flat deck is 1.5–2.0 m, but the width of arch deck is 2.5 m, an increase of 25–60%. Therefore, for a PSC girder bridge with a total width 10 m, a number of required girders needed for ordinary flat RC deck and arch deck is 5 and 4, respectively. This means that one less girder can be required, which means that 20% of girder construction cost can be achieved by using arch deck over ordinary flat deck. In this study, precasted RC arch deck is developed and manufactured to evaluate structural performance of the deck. The study results showed that arch deck has performance exceeding ordinary flat deck and can be used as alternative decks for precasted PSC I-girder bridge construction. The study results are discussed in detail in the paper.

Crack width control of precast deck loop joints for continuous steel-concrete composite girder bridges

Shim, Changsu,Lee, Chidong Techno-Press 2020 Advances in concrete construction Vol.10 No.1

Precast deck joints have larger crack width than cast-in-place concrete decks. The initial crack typically occurs at the maximum moment but cracks on precast joints are significant and lead to failure of the deck. The present crack equation is applied to cast-in-place decks, and requires correction to calculate the crack width of precast deck joints. This research aims to study the crack width correction equation of precast decks by performing static tests using high strength and normal strength concrete. Based on experimental results, the bending strength of the structural connections of the current precast deck is satisfied. However it is not suitable to calculate and control the crack width of precast loop connections using the current design equation. A crack width calculation equation is proposed for crack control of precast deck loop joints. Also included in this paper are recommendations to improve the crack control of loop connections.

2거더 연속합성형교 요철형 루프이음 프리캐스트 바닥판의 피로성능

이한주,여운영,신동호,김인규,박세진 한국구조물진단유지관리공학회 2019 한국구조물진단유지관리공학회 논문집 Vol.23 No.1

Structural performance and serviceability of precast deck system are mostly determined by connection details between precast decks. Particularly, since the bridge deck is under repeated loads such as traffic loads, fatigue behavior and performance of joints should be investigated. In this study, a two-girder continuous composite bridge specimen was fabricated using the asymmetric ribbed loop joints, and static and fatigue load tests were conducted to evaluate the structural behavior and the crack pattern of the bridge deck. From the test results, the proposed precast deck system resulted in sufficient fatigue performance and failure strength. Therefore, the proposed precast deck system can be applied to the connection part of precast decks effectively. 프리캐스트 바닥판 공법은 바닥판간 이음부가 존재하며, 이음부의 연결성능에 따라 전체 교량 구조물의 성능이 좌우되므로 이음부의 연결성능 확보가 중요한 요소이다. 특히, 교량바닥판은 차량하중과 같은 반복하중을 받는 구조물이므로 피로하중에 대한 이음부의 거동 및 성능평가가 이루어져야 한다. 본 연구에서는 비대칭 요철형 루프이음을 적용한 2거더 연속합성형 교량을 제작하여 정적 및 200만회 반복하중의 피로실험을 통해 프리캐스트 바닥판의 구조적 거동 및 균열양상을 검토하였다. 실험결과, 제안된 프리캐스트 바닥판 연결시스템은 균열 폭, 누수, 인장철근의 응력 등 충분한 피로성능 및 파괴강도를 확보하는 것으로 나타났으며, 프리캐스트 바닥판 이음부에 효과적으로 적용 가능할 것으로 판단된다.

프리캐스트 콘크리트 교량바닥판 female-female이음부의 전단실험

김영진,김영진,김종희 한국콘크리트학회 1998 콘크리트학회지 Vol.10 No.6

본 연구는 수직전단하중에 대한 프리캐스트 바닥판간 이음부거동을 규명하고 수직전단력 전달에 유리한 이음부 구조도출을 위해 female-female 형식의 이음부를 제안하고, 실험 및 유한요소해석을 수행한 것이다. 경사각, 이음부깊이/높이 및 구속응력을 변수로 총 18개의 실험체에 대한 실험 및 유한요소해석결과 ,이음부의균열저항성 개선을 위해서는 경사각이 60。, D/H가 1/4일 경우가 유리하며 측방향구속으로 이음부를 압축상태로 유지하는 것이 이음부 균열방지에 효과적임을 알았다. Increase of traffic volume in recent years results in deterioration of the bridge slab, which is directly subjected ot vehicle loads. Where extensive repair is necessary, replacement or enhancement of load carrying capacity using full depth precast concrete deck is often the most practical solution. Precast deck system has transverse joints between adjacent precast decks. Vertical shear forces occur when a vehicle wheel load is carried by precast decks and the joints are used to transfer the load to an adjacent deck. Effective load transfer between precast decks is critical for integral behavior. Finite element analysis and tests were run on the proposed femal-to-female type joint. 18 joint specimens were tested to investigate the effects of angle. D/H, and confining stress under static load. Results indicate joint with angle of 60$^{\circ}$ and D/H of 1/4 shows the improved load carrying capacity on crack. It is effective in protecting the cracking of joints to keep the joint in compression using confining stress.

Structural behavior of precast concrete deck with ribbed loop joints in a composite bridge

Dong-Ho Shin,Chul-Hun Chung,Daewoo Institute of Construction Techno,Se-Jin Park,In-Gyu Kim,Young-Jin Kim,Tae-Kwan Byun,Myoung-Gu Kang 국제구조공학회 2016 Smart Structures and Systems, An International Jou Vol.17 No.4

This study is intended to propose a precast bridge deck system, which has ribbed loop joints between the decks and lacks internal tendons to improve the workability of existing precast deck system. A composite bridge deck specimen was fabricated using the proposed precast deck system, and static and fatigue load tests were conducted to evaluate the structural behavior and the crack pattern of the deck. Leakage test of the deck joints was also conducted and finite element analysis was carried out to compare with the test results.

급속 시공을 위한 일체형 프리캐스트 바닥판의 구조성능 평가

이상열 ( Sang Youl Lee ) 한국복합신소재구조학회 2015 복합신소재구조학회논문집 Vol.6 No.3

In this study we developed an integrated precast concrete decks for a rapid construction. The structural performance in the integrated precast bridge decks is evaluated by real-scale test bed and detailed finite element analyses. The numerical analysis results were compared with the experimental data from a real-scaled single-span precast/prestressed concrete bridge decks under truck loading. Parametric studies are focused on the various effects of external loads on the structural behavior for different locations and measuring points on the precast bridge decks. The assessment in this study indicates that the integrated precast bridge decks show an excellent structural performance as expected.

루프이음 반단면 프리캐스트 패널을 이용한 PSC 바닥판의 강도평가

정철헌(Chung Chul Hun),김유석(Kim Yu Seok),현병학(Hyun Byung Hak),김인규(Kim In Gyu) 대한토목학회 2009 대한토목학회논문집 A Vol.29 No.5A

프리캐스트 패널은 교량바닥판의 합성 구조부재로서 사용된다. 프리캐스트 패널의 횡방향 강재는 교량바닥판의 주철근 역할을 하며, 또한, 패널은 상부의 현장타설 콘크리트 시공시 거푸집 대용으로 적용된다. 이 연구에서는 프리캐스트 패널과 현장타설 바닥판의 합성효과를 위해 패널 상부에 도입되는 전단철근 필요성을 확인하였다. 또한, 프리캐스트 패널을 갖는 합성 바닥판에서 패널간에는 횡방향 이음부의 연속적인 거동이 요구된다. 본 연구에서는 전단철근과 루프이음을 갖는 합성바닥판의 정적실험을 수행하였다. 실험결과로부터 바닥판의 연속성 확보를 위한 루프철근 이음부의 연속성을 확인하고, 패널과 현장타설 바닥판 사이의 합성효과를 확인하였다. 전단철근이 있는 합성바닥판은 합성효과의 증가로 인해 전단철근이 없는 바닥판에 비해 약 140~164%의 극한내력을 보인다. 따라서 접합면에 도입되는 전단철근은 파괴시까지 합성거동을 확보해주는 역할을 하는 것으로 판단된다. The panels are used as a composite part of the completed deck. They replace the main bottom transverse deck reinforcement and also serve as a form surface for the cast-in-place concrete upper layer that contains the top of deck reinforcement. Research has also demonstrated that mechanical shear ties on the top of the panels are required. In a composite deck with precast panels, it is required to notice behavior of transverse joints between panels. In this paper, static tests of composite deck with shear ties and loop joints were conducted. From the results, the validity of loop joints for continuity of deck was observed. Also, a composite behavior was abserved between precast panel and slab concrete. Tested composite decks with shear ties have 140~164% ultimate strength than have no shear ties due to the increase of composite action. Therefore, the shear ties between the slabs were sufficient to enforce composite flexural behavior to failure.

루프이음 반단면 프리캐스트 패널을 이용한 교량 바닥판의 피로성능

정철헌(Chung Chul Hun),임승준(Lim Seung Jun),김현준(Kim Hyun Jun) 대한토목학회 2010 대한토목학회논문집 A Vol.30 No.1A

프리캐스트 패널은 교량바닥판의 합성 구조부재로서 사용된다. 프리캐스트 패널의 횡방향 강재는 교량바닥판의 주철근 역할을 하며, 또한, 패널 상부의 현장타설 콘크리트 시공시 거푸집 대용으로 적용된다. 그러나 프리캐스트 패널의 장점을 살리기 위해서는 필연적으로 갖게 되는 구조적 특징이자 취약점이 될 수 있는 이음부 부분에 대한 이해와 지식이 필요하다. 특히 교량바닥판은 차량하중과 같은 반복하중을 받는 구조물이므로 피로하중에 대한 이음부의 거동 및 성능 평가가 이루어져야 한다. 본 연구에서는 전단철근과 루프이음부를 갖는 프리캐스트 패널 합성바닥판의 피로실험을 수행하였다. 피로실험은 고정점 반복하중과 윤하중을 적용하여 수행되었다. 피로에 대한 현행 설계기준을 고려하고 이음부의 피로파괴 특성과 반복하중 하에서의 사용성 평가를 위해 결과 분석을 수행하였다. The panels are used as a composite part of the completed deck. They replace the main bottom transverse deck reinforcement and also serve as a form surface for the cast-in-place concrete upper layer that contains the top of deck reinforcement. However, in order to apply the precast panels to bridges properly, it is necessary to fully understand the structural characteristics of joint in precast panels. Particularly, since the bridge deck is under repeated loads such as traffic loads, fatigue behavior and characteristics of joint should be investigated. In this paper, fatigue tests of composite deck with shear ties and loop joints were conducted. The fatigue tests were conducted with an application of repeated loading and wheel loading. Test results were analyzed to examine the current design code for fatigue of reinforcement bar and serviceability under repeated loading.

이음철근이 보강된 반단면 프리캐스트 판넬 이음부의 강도 안전성 평가

황훈희 한국안전학회 2019 한국안전학회지 Vol.34 No.2

The Half-depth precast deck is a structural system that utilizes pre-cast panels pre-built at the factory as formwork at the construction stage and as a major structural member at the same time after completion. These systems have joints between segments, and the detail and performance of the joints are factors that have a very large impact on the quality, such as the constructability and durability of the bridge decks. In this study, strength performance evaluation was performed for improved joints using connecting rebar by experimental method. Static loading tests were conducted on the test specimen with improved joint, those with existing joint and those without joint. The test results of the specimens were compared to each other, and the flexural strength required by the design was compared. The flexural strength required in the design was presented by finite element analysis. It has been shown that the flexural strength of the specimens with joints were more than twice that required by the design. But the flexural strength of the specimen with existing joint was about 84% of that without joint. The flexural strength of the specimen with improved joints was a nearly similar degree of that compared to the specimen without joint. And a comparison of the moment-deflection relationship curves of the two specimens also shows a very similar flexural behavior. It is confirmed that improved joint has sufficient flexural strength. In addition to strength, the bridge decks require serviceability, such as deflection and cracking, and in particular, fatigue resistance due to repetitive live loads is an important performance factor. Therefore, further verification studies are required.

Flexural Performance of Prefabricated Composite Girders along with Precast Deck-to-Girder Continuous Connections

Choi Byung H.,Diep Hung Thanh,문지호 한국강구조학회 2024 International Journal of Steel Structures Vol.24 No.1

Recently, a great amount of research has been carried out to resolve a growing need for durable and resilient highway bridge construction/reconstruction systems in many countries. As a part of such studies, prefabricated composite girders with innovative precast deck-to-girder continuous connections have been proposed that facilitate construction by eliminating interference during on-site processes. This study aims to fi gure out the eff ects on the fl exural performance of the prefabricated composite girders along with the non-interference deployment of the precast deck-to-girder interface connections. In this study, two test specimens of the prefabricated composite girder were designed. Ultimate bending tests were conducted to experimentally evaluate the behavior of shear interfaces and fl exural performances of the test specimen girders. It was revealed from this study that the intersection of the lap connection between the transverse deck reinforcement and the shear connectors will have a signifi cant eff ect on the fl exural performance of the prefabricated composite girder. The fl exural performance of the prefabricated composite girder with intersected connection type is ensured while the non-intersected connection type infl uences the fl exural performance more seriously than the intersected connection type. The AASHTO LRFD specifi cations appears applicable to the existing intersected connection details. Further, a series of parametric studies based on the verifi ed fi nite element model were performed to examine the infl uence of various dominant factors on the fl exural moment strength of the prefabricated composite girder. From the results of parametric studies, conclusions were drawn. The results of this study could be used for future research to establish a procedure for evaluating the bending resistance capacity of prefabricated composite girders based on structural ductility through rotating capacity.