• Title/Summary/Keyword: Prefabricated

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Seismic Performance of Prefabricated Composite Column for Accelerated Bridge Construction (급속시공을 위한 조립식 합성교각의 내진성능 평가)

  • Lee, Jung-Woo;Chin, Won-Jong;Joh, Chang-Bin;Kwark, Jong-Won
    • Journal of the Korean Society for Railway
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    • v.13 no.4
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    • pp.425-430
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    • 2010
  • This paper investigates the seismic behavior of a prefabricated composite column which is made by onsite connection of precast composite column segments to accelerate bridge construction. Quasi-static cyclic loading tests were performed on three prefabricated composite columns with different connection details to find their seismic capacity. Test results show that the onsite connections remains in elastic range and no slip is observed as designed in spite of plastic hinge formation at the column. The test results also indicate that the prefabricated composite column has better overall seismic capacity compared to a conventional reinforced concrete column with seismic details.

Development of a Gable-roofed Prefabricated Pipe-house for Improvement of Snow Endurance (내설성 향상을 위한 지붕형 조립식 파이프하우스의 개발)

  • Yang, In-Kyoo;Nam, Sang-Woon
    • Journal of The Korean Society of Agricultural Engineers
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    • v.51 no.3
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    • pp.71-78
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    • 2009
  • Pipe section of bending part at the arch type pipe-house showed an ellipse with oblateness of 0.076 on the average. Flexural rigidity of bending part decreased by average 6.3% than that of an original round shape section. The deflection of arch type pipe-house measured by model experiments showed much bigger than the result of structural analysis. In case of arch type pipe-house, we supposed that the decrease of flexural rigidity for the bending part of pipes had an effect on deflection of roof under the working load. This effect should be considered in the structural analysis. Bending resistance of gable type pipe-house used a prefabricated connector which developed in this study showed about $1.5{\sim}1.8$ times stronger than that of the existing arch type or gable type processed bending. Therefore, we supposed that the gable-roofed prefabricated pipe-house is safer than arch type or bent gable type in case of heavy snowfall. According to house scales and section properties of steel pipe in use, safe snow depths and rafter intervals were presented for design of gable-roofed prefabricated pipe-house. Their standards were established in the range of the durable models recommended by RDA, and the comparative examinations were conducted by means of structural analysis. It was evaluated that the developed greenhouse model had a high applicability in the field.

Design Comparison of Totally Prefabricated Bridge Substructure Systems Designed by Present Design and LRFD Methods (현행설계법 및 하중저항계수설계법에 의한 완전 조립식 교량 하부구조의 설계결과 비교)

  • Kim, Tae-Hoon;Kim, Young-Jin;Shin, Hyun-Mock
    • Journal of the Earthquake Engineering Society of Korea
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    • v.15 no.2
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    • pp.11-22
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    • 2011
  • The design comparison and nonlinear analysis of totally prefabricated bridge substructure systems are performed. The prefabricated bridge substructures are designed by the methods of present design and load and resistance factor design (LRFD). For the design, the current Korea Highway Bridge Code (KHBD), with DB-24 and DL-24 live loads, is used. This study evaluates the present design method of KHBD (2005) and AASHTO-LRFD (2007) for totally prefabricated bridge substructure systems. A computer program, named RCAHEST (Reinforced Concrete Analysis in Higher Evaluation System Technology), for the analysis of reinforced concrete structures, was used.

Flexural analysis of transverse joints of prefabricated T-girder bridge superstructure

  • Kye, Seungkyung;Jung, Hyung-Jo;Park, Sun-Kyu
    • Structural Engineering and Mechanics
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    • v.77 no.1
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    • pp.89-102
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    • 2021
  • Rapid construction of prefabricated bridges requires minimizing the field work of precast members and ensuring structural stability and constructability. In this study, we conducted experimental and analytical investigations of transverse joints of prefabricated T-girder bridge superstructures to verify the flexural performance and serviceability. In addition, we conducted parametric studies to identify the joint parameters. The results showed that both the segmented and continuous specimens satisfied the ultimate flexural strength criterion, and the segmented specimen exhibited unified behavior, with the flexural strength corresponding to that of the continuous specimen. The segmented specimens exhibited elastic behavior under service load conditions, and the maximum crack width satisfied the acceptance criteria. The reliability of the finite element model of the joint was verified, and parametric analysis of the convexity of the joint section and the compressive strength of the filler concrete showed that the minimum deflection and crack width occurred at a specific angle. As the strength of the filler concrete increased, the deflection and crack width decreased. However, we confirmed that the reduction in the crack width was hardly observed above a specific strength. Therefore, a design suitable for prefabricated bridges and accelerated construction can be achieved by improving the joint specifications based on the required criteria.

Seismic performance of prefabricated reinforced concrete column-steel beam sub-assemblages

  • Bai, Juju;Li, Shengcai
    • Earthquakes and Structures
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    • v.22 no.2
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    • pp.203-218
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    • 2022
  • In this paper, quasi-static tests were carried out on three prefabricated reinforced concrete column-steel beam (RCS) sub-assemblages with floor slabs and one comparison specimen without floor slab. The effects of axial compression and floor slab on the seismic performance were studied, and finite element simulations were conducted using ABAQUS. The results showed that the failure of prefabricated RCS sub-assemblages with floor occurred as a joint beam and column failure mode, while failure of sub-assemblages without floor occurred due to beam plastic hinge formation. Compared to the prefabricated RCS sub-assemblages without floor slab, the overall stiffness of the sub-assemblages with floor slab was between 19.2% and 45.4% higher, and the maximum load bearing capacity increased by 26.8%. However, the equivalent viscosity coefficient was essentially unchanged. When the axial compression ratio increased from 0.24 to 0.36, the hysteretic loops of the sub-assemblages with floor became fuller, and the load bearing capacity, ductility, and energy dissipation capacity increased by 12.1%, 12.9% and 8.9%, respectively. Also, the initial stiffness increased by 10.2%, but the stiffness degradation accelerated. The proportion of column drift caused by beam end plastic bending and column end bending changed from 35% and 46% to 47% and 36%, respectively. Comparative finite element analyses indicated that the numerical simulation outcomes agreed well with the experimental results.

Mechanical behavior of prefabricated steel-concrete composite beams considering the clustering degree of studs

  • Gao, Yanmei;Fan, Liang;Yang, Weipeng;Shi, Lu;Zhou, Dan;Wang, Ming
    • Steel and Composite Structures
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    • v.45 no.3
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    • pp.425-436
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    • 2022
  • The mechanical behaviors of the prefabricated steel-concrete composite beams are usually affected by the strength and the number of shear studs. Furthermore, the discrete degree of the arrangement for shear stud clusters, being defined as the clustering degree of shear stud λ in this paper, is an important factor for the mechanical properties of composite beams, even if the shear connection degree is unchanged. This paper uses an experimental and calculation method to investigate the influence of λ on the mechanical behavior of the composite beam. Five specimens (with different λ but having the same shear connection degree) of prefabricated composite beams are designed to study the ultimate supporting capacity, deformation, slip and shearing stiffness of composite beams. Experimental results are compared with the conventional slip calculation method (based on the influence of λ) of prefabricated composite beams. The results showed that the stiffness in the elastoplastic stage is reduced when λ is greater than 0.333, while the supporting capacity of beams has little affected by the change in λ. The slip distribution along the beam length tends to be zig-zagged due to the clustering of studs, and the slip difference increases with the increase of λ.

Assessment of Drainage Properties of PBDs(Prefabricated Board Drains) for Soft Soil Reinforcement

  • Jeon, Han-Yong;Kim, Hong-Gwan;Chang, Yong-Chai;Chung, Chin-Gyo
    • Proceedings of the Korean Fiber Society Conference
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    • 2003.10a
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    • pp.105-105
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    • 2003
  • Theoretical studies have been performed for drainage and filtration characteristics, low consolidation rate of sandmat and prefabricated horizontal and vertical drain. Discussion on quality control and methodology, cost analysis for sandmat and prefabricated horizontal drains were performed.

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A study on the Analysis and Effects for Unbalanced Swing Characteristics of Prefabricated Jumper Devices (조립식 점퍼장치의 불평형 횡진의 해석과 영향 연구)

  • Sohn, H.K.;Lee, E.W.
    • Proceedings of the KIEE Conference
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    • 2000.07b
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    • pp.819-821
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    • 2000
  • The purpose of swing analysis for prefabricated jumper devices are to prevent flashover between jumper device and tower post. To prevent flashover. proper weight is add to the horizontal rod. This paper is a proposed to the analysis methods and the effects for unbalanced swing characteristics of prefabricated jumper devices. And the proposed technique is applied with the 345kV and 765kV transmission lines.

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Characteristics of Walls Supported by Prefabricated Strut (조립식 버팀보로 지지된 흙막이 구조물의 거동 특성에 관한 연구)

  • 김낙경;박종식
    • Proceedings of the Korean Geotechical Society Conference
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    • 2003.03a
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    • pp.553-560
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    • 2003
  • From the analytical standpoint, it is advantageous to consider the behavior of supported walls as plane strain condition. But supported walls constitute geotechnical problems which, in strut terms, are not plane strain cases. These represent differences between the measured and the predicted due to the stiffness and spacing of supported walls and the behavior of discontinuous walls such as solider beams with lagging. This study is to investigate simulations of a system behavior along a horizontal section of walls supported by prefabricated strut. Using a beam column method, relative effects associated with prefabricated strut stiffness and spacing in a systematic behavior were investigated.

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