• Title/Summary/Keyword: prefabricated system

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Comparison of Totally Prefabricated Bridge Substructure Designed According to Korea Highway Bridge Design (KHBD) and AASHTO-LRFD

  • Kim, Tae-Hoon
    • International Journal of Concrete Structures and Materials
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    • v.7 no.4
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    • pp.319-332
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    • 2013
  • The purpose of this study was to investigate the design comparison of totally prefabricated bridge substructure system. Prefabricated bridge substructure systems are a relatively new and versatile alternative in substructure design that can offer numerous benefits. The system can reduce the work load at a construction site and can result in shorter construction periods. The prefabricated bridge substructures are designed by the methods of Korea Highway Bridge Code (KHBD) and load and resistance factor design (AASHTO-LRFD). For the design, the KHBD with DB-24 and DL-24 live loads is used. This study evaluates the design method of KHBD (2005) and AASHTO-LRFD (2007) for totally prefabricated bridge substructure systems. The computer program, reinforced concrete analysis in higher evaluation system technology was used for the analysis of reinforced concrete structures. A bonded tendon element is used based on the finite element method, and can represent the interaction between the tendon and concrete of a prestressed concrete member. A joint element is used in order to predict the inelastic behaviors of segmental joints. This study documents the design comparison of totally prefabricated bridge substructure and presents conclusions and design recommendations based on the analytical findings.

Prefabricated Apartments Project Using Precast Concrete Large Panel System (프리캐스트 콘크리트 대형 패널을 이용한 조립식 아파트 공사)

  • 박의식
    • Proceedings of the Korea Concrete Institute Conference
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    • 1989.10a
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    • pp.49-52
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    • 1989
  • This report introduces the large scale prefabricated apartment project in Saudi Arabia designed and built by Hyundai Engineering and construction Co. as turn-key basis from ministry of Public works and ltousing of Saudi Arabia. This project using precast large panel system is 7,600 dwelling unit, total building area 1.8 mil sguare meters. Large panel system is a kind of industrialized building method which classified as monolithic system, total system and structural system. Hyundai Engineering and Construction Co. develop his own prefabricated large panel system for this project and named "HYUNDAI SYSTEM". The key point of this system is vertical and horizontal joints between panels. Also stability of whole building structure is especially important for this kind of prefabricated building. building.

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Upgrading flexural performance of prefabricated sandwich panels under vertical loading

  • Kabir, M.Z.;Rezaifar, O.;Rahbar, M.R.
    • Structural Engineering and Mechanics
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    • v.26 no.3
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    • pp.277-295
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    • 2007
  • 3-D wall panels are used in construction of exterior and interior bearing and non-load bearing walls and floors of building of all types of construction. Fast construction, thermal insulation, reduced labor expense and weight saving are the most well pronounced advantage of such precast system. When the structural performance is concerned, the main disadvantage of 3D panel, when used as floor slab, is their brittleness in flexure. The current study focuses on upgrading ductility and load carrying capacity of 3D slabs in two different ways; using additional tension reinforcement, and inserting a longitudinal concentrated beam. The research is carried on both experimentally and numerically. The structural performance in terms of load carrying capacity and flexural ductility are discussed in details. The obtained results could give better understanding and design consideration of such prefabricated system.

Development of Top-Down Connection System to Solve the Problem of Construction Tolerances in Installing Prefabricated Beams to Pre-founded Columns (시공오차가 있는 선기초기둥에 공장제작보의 설치가 용이한 탑다운공사용 접합기술개발)

  • Kim, Seung-Weon;Jung, Hee-Weon;Park, Dae-Yung;Kim, Dong-Gun;Park, Joo-Hyun
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2011.05b
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    • pp.25-30
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    • 2011
  • Almost prefounded columns for top-down construction certainly have construction tolerances in plan and plumbness. Therefore, it is very difficult to connect prefabricated beams to prefounded columns at each floor level after excavation by usual top-down connection method and this usual connection method leads to long construction time, increasing cost and decreasing quality. This paper presents a new method for connecting prefabricated beam to prefounded column with GROUT-JACKET CONNECTION SYSTEM consisting of sleeve, bearing-shear bands and grout. Details and illustrations of the connections and applications by GROUT-JACKET CONNECTION SYSTEM for the top-down construction are also included in this paper.

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Seismic performance of prefabricated bridge columns with combination of continuous mild reinforcements and partially unbonded tendons

  • Koem, Chandara;Shim, Chang-Su;Park, Sung-Jun
    • Smart Structures and Systems
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    • v.17 no.4
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    • pp.541-557
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    • 2016
  • Prefabricated bridge substructures provide new possibility for designers in terms of efficiency of creativity, fast construction, geometry control and cost. Even though prefabricated bridge columns are widely adopted as a substructure system in the bridge construction project recently, lack of deeper understanding of the seismic behavior of prefabricated bridge substructures cause much concern on their performance in high seismic zones. In this paper, experimental research works are presented to verify enhanced design concepts of prefabricated bridge piers. Integration of precast segments was done with continuity of axial prestressing tendons and mild reinforcing bars throughout the construction joints. Cyclic tests were conducted to investigate the effects of the design parameters on seismic performance. An analytical method for moment-curvature analysis of prefabricated bridge columns is conducted in this study. The method is validated through comparison with experimental results and the fiber model analysis. A parametric study is conducted to observe the seismic behavior of prefabricated bridge columns using the analytical study based on strain compatibility method. The effects of continuity of axial steel and tendon, and initial prestressing level on the load-displacement response characteristics, i.e., the strain of axial mild steels and posttensioned tendon at fracture and concrete crushing strain at the extreme compression fiber are investigated. The analytical study shows the layout of axial mild steels and posttensioned tendons in this experiment is the optimized arrangement for seismic performance.

Analysis of seismic behaviors of digging well foundation with prefabricated roots

  • Wang, Yi;Chen, Xingchong;Zhang, Xiyin;Ding, Mingbo;Gao, Jianqiang;Lu, Jinhua;Zhang, Yongliang
    • Earthquakes and Structures
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    • v.21 no.6
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    • pp.641-652
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    • 2021
  • Digging well foundation has been widely used in railway bridges due to its good economy and reliability. In other instances, bridges with digging well foundation still have damage risks during earthquakes. In this study, a new type of digging well foundation with prefabricated roots was proposed to reduce earthquake damage of these bridges. Quasi-static tests were conducted to investigate the failure mechanism of the root digging well foundation, and then to analyze seismic behaviors of the new type well foundation. The testing results indicated that these prefabricated roots could effectively limit the rotation and uplift of the digging well foundation and increase the lateral bearing capacity of the digging well foundation. The elastic critical load and ultimate load can be increased by 69% and 36% if prefabricated roots were added in the digging well foundation. The prefabricated roots drived more soil around the foundation to participate in working, the stiffness of the bridge pier with root digging well foundation was improved. Moreover, the root participation could improve the energy dissipation capacity of soil-foundation-pier interaction system. The conclusions obtained in this paper had important guiding significance for the popularization and application of the digging well foundation with prefabricated roots in earthquake-prone zones.

Research on Facility Layout of Prefabricated Building Construction Site

  • Yang, Zhehui;Lu, Ying;Zhang, Xing;Sun, Mingkang;Shi, Yufeng
    • International conference on construction engineering and project management
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    • 2017.10a
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    • pp.42-51
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    • 2017
  • Due to the high degree of mechanization and the good environmental benefits, the prefabricated buildings are being promoted in China. The construction site layout of the prefabricated buildings has important influence on its safety benefit. However, few scholars have studied the safety problem on it. Firstly, in order to give a follow-up study foreshadowing the characteristics of prefabricated buildings are analyzed, the research assumptions are given and three types of safety buffers are established. And then a mult-objective model for the prefabricated buildings site layout is presented: taking into account the limits of noise, the coverage of the tower crane and the possibility of exceeding boundaries and overlapping, the constraints are and designed established respectively; Based on the improved System Layout Planning (SLP) method, the efficiency\cost\safety interaction matrices among the facilities are also founded for objective function. For the sake of convenience, a hypothetical facility layout case of the prefabricated building is used, the optimal solution of that is obtained in MATLAB with particle swarm algorithm (PSO), which proves the effectiveness of the model presented in this paper.

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An Experimental Study on Heat Transmission Characteristics of the Conventional and Prefabricated Ondol (기존온수온돌과 조립식 온수온돌의 전열특성에 관한 실험적 연구)

  • Min, J.H.;Lee, C.G.;Jang, M.S.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.7 no.4
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    • pp.611-621
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    • 1995
  • The objectives of this study are to find out and to analyze the heat transmission characteristics of the conventional and prefabricated Ondol systems. To compare the thermal characteristics of these Ondol, a real sized Ondol model is set in a chamber. Hot water whose temperature is varied from $45^{\circ}C$ to $60^{\circ}C$ with $5^{\circ}C$ interval is supplied to each Ondol system. At that time the temperature distribution of floor surface, the amount of supplied heat, the heat radiation aspect and the heat loss from the floor to the underground are measured and analyzed simultaneously. As a result, even if the supplied hot water temperature to the prefabricated Ondol panel is lower by about $5^{\circ}C$ than that of the conventional Ondol panel, the net radiant effect is same. Heat radiation efficiency of the prefabricated Ondol panel is over 5% better than that of the conventional Ondol panel. It takes 12 hours for the conventional Ondol and 45 minutes for the prefabricated Ondol, respectively to reach steady state.

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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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Feasibility Analysis on the Application of Eco-friendly Prefabricated Rainwater Detention System in Grit Chamber and Permanent Pond by the Two-dimensional Diffusion-wave Analysis Model (2차원 확산파 해석모형을 통한 침사지겸 저류지의 친환경 조립식 빗물침투저류시설 적용 타당성 분석)

  • Kim, Ho-jin;Choi, Hee-Yong;Lee, Tae-Gyu;Choi, Hyeonggil
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2022.11a
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    • pp.185-186
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    • 2022
  • In this study, a numerical analysis was conducted using a two-dimensional diffusion-wave analysis model to analyze the validity about the application of eco-friendly prefabricated rainwater detention system in grit chamber and permanent pond. As a result of the analysis, it is confirmed that the flood prevention effect, such as a decrease in peak flow rate and a delay in peak time, is excellent, so it is considered reasonable to apply eco-friendly prefabricated rainwater detention system in grit chamber and permanent pond.

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