• International Journal of Concrete Structures and Materials
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• 제7권4호
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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.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2011년도 춘계 학술논문 발표대회 2부
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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.

• Smart Structures and Systems
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• 제17권4호
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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.

• 국제학술발표논문집
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• The 7th International Conference on Construction Engineering and Project Management Summit Forum on Sustainable Construction and Management
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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.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1998년도 봄 학술발표회 논문집
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• pp.119-126
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• 1998

• 한국공간구조학회논문집
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• 제20권3호
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• pp.71-79
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• 2020

In this paper, the hybrid prefabricated retrofit method that improve structural performance and reduce construction period was developed by using a finite element analysis. The hybrid prefabricated retrofit method consist of a Z-shaped side plate, a L-shaped lower plate, and a bottom plate containing an steel plate with openings. This shape has advantage that a retrofit method is possible regardless of the size of the beams and a follow-up process such as reinforcement bars placing are not required. The finite element analysis of hybrid Prefabricated retrofit method showed the most ideal stress distribution when the thickness of bottom plate was 10mm, the thickness of the L-shaped lower plate was 5mm, the thickness of the Z-shaped side plate was 2.5mm, and the bolt spacing was 200mm. The bending strength equation of Hybrid prefabricated retrofit method was proposed through the plastic stress distribution method in KDS 41 31 00. The result of Comparison the proposed equation with the finite element analysis, it is determined that the design of hybrid prefabricated retrofit method is possible through the KDS 41 31 00.

• International Journal of Safety
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• 제9권1호
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• pp.21-29
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• 2010

When a new member of a scaffold is developed, it is necessary to follow the standard. Therefore, all scaffolds will assume the same structure. The aim of this study was to establish a new method for evaluating scaffold performance. In the present study, a buckling analysis of prefabricated scaffolds was executed, using the shear rigidity of the vertical and the horizontal frames as parameters. From the results, an equation is proposed for evaluating the strength of prefabricated scaffolds.

• 한국산학기술학회논문지
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• 제11권7호
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• pp.2670-2675
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• 2010

한옥에서 축부는 건물의 외관과 실내 환경, 공사기간 및 공사비와 밀접한 관련을 지닌 부분이다. 본 연구에서는 전통적인 시공법을 분석하여 전통 한옥의 장점으로서의 특성을 유지하면서 개선된 한옥 축부의 시공법을 제안하였다. 그 개선안은 기성품의 사용, 전체 공정의 건식 조립공법화, 기둥과 벽체의 일괄 시공, 기밀성과 단열성능 향상 등의 특성을 지닌다. 앞으로 시제품의 제작과 성능 시험 등의 단계를 거쳐야 하겠지만 한옥의 형태적 특성을 유지하면서 공사기간과 공사비를 줄이는데 일조할 수 있을 것으로 기대한다.

• 한국건축시공학회지
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• 제15권6호
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• pp.631-639
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• 2015

유닛모듈러 공법에서는 정밀 제작된 유닛모듈과 시공정밀도가 낮은 기초부의 접합부에서 수평 정밀도 차이가 발생한다. 이러한 정밀도 차이로 인하여 상부 유닛모듈이 뒤틀리거나, 간격이 벌어지는 등 다양한 문제가 야기될 수 있다. 이러한 배경에서 본 연구는 Pre-Fab 독립기초의 높이조절이 가능한 공법을 개발하는 것을 목적으로 하였다. 이를 위하여 본 연구에서는 볼트와 너트를 이용한 높이조절 공법을 제안하고 시공 상세도와 시공순서를 제시하였다. 그리고 구조 시뮬레이션을 수행하여 구조적 안정성을 확인하였다. 향후 개발된 높이조절 공법의 mock-up 시험, 경제성 분석 등을 실시하여 시공성과 유용성을 검토할 예정이다.

• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.132-137
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• 2015

A modular construction method includes factory-prefabricated room-sized volumetric units. Although low-rise buildings have been constructed worldwide using this method for more than 30 years, it is a relatively new technology in high-rise construction. There are three basic methods of constructing high-rise buildings using modular construction: the core method, the core-and-podium combination method, and the modular in-fill method. While the first two have been used in the USA and in several European countries, the third method, introduced in 2011 by an international cruise ship development firm, is a rather new approach for which there are few case histories. Therefore, its applicability and construction feasibility should be verified. As a pilot study to test the applicability of the modular in-fill method, a 12-story residential building was built in Korea. This paper describes a case study of the pilot project. The advantages and disadvantages of the method and its applicability in terms of cost effectiveness and construction schedule management were evaluated.