Regarding deck replacement of bridge structures, it is important to minimize total construction time and costs ensuring safety of it. Since cast-in-place concrete deck takes a long time for replacement, precast concrete deck system is considered as an effective alternative. Structural performance, economic feasibiltity and constructability of precast deck system are mostly affected by joint properties between precast deck panels. To improve the joint properties, this research presents a new precast deck system of ribbed section joint with protruding lower concrete and verifies tits applicability through parameter tests.

In this study, A preliminary research has been attempted by design and strength analysis on a series of precast ultra high-strength concrete slab systems in order to evaluate. To compare with conventional reinforced concrete slabs, current slab systems can improve serviceability and ultimate load capacities, crack control, and durability, so as to apply in long span, lightweight, and slender building slab systems.

The development and field application of the environment friendly Precast concrete by replacing the blast furnace slag were examined. As a result, it was found that compressive strength of Precast concrete used 50% of blast furnace slag was similar to Plain. While 70% of blast furnace slag was slightly decreased. In the result of Mock-up Test, the compressive strength of Precast concrete used 50% of blast furnace slag was satisfied with the target strength. but greening phenomenon occurred. Although greening occurred on the surface of the Precast concrete, it was gradually disappeared over the age. Therefore, the use of blast furnace slag was available up to 50%.

Precast modular bridge was designed by ultimate strength design method(USD), though it is aimed at development of the world's first permanent bridge applying modular technology. Therefore, it is necessary to review the LSD in order to achieve the goal. In this study, the slab-type precast modular bridge(span 8m) was examined on the stability of bending moment in the longitudinal direction by the LSD.

1994년 성수대교 붕괴사고 이후 강구조물의 품질 관리를 위해 철강구조물제작공장 인증제도가 건설기술관리법에 도입되어 법정임의 인증제도로 운영되고 있다. 그러나 콘크리트 부재의 공장 생산 방식인 PC (Precast Concrete)에 대해 국가적인 품질인증 체계는 마련되어있지 않다. 이에 건축 구조용 PC를 대상으로 적절한 품질인증제도 도입을 위해 북미, 유럽, 일본 등의 PC 품질인증제도를 조사하였다. 북미에서 PC 공장인증제도를 운영하고 있는 곳은 PCI, NPCA, CPCI 등이 있다. 유럽에서 PC 제품을 판매하기 위해서는 CPR 305/2011을따르도록 법으로 정해져 PC 제품을 포함한 모든 건설 제품은 2013년 7월부터 CE 마크를 의무적으로 부착해야 한다. 일본의 경우 토목용PC 제품은 제품인증인 JIS 마크 인증을 받도록 되어 있고 건축 구조용 PC를 생산하는 공장은 일본 프리패브협회의 심사를 받고 있다. 이런 조사 결과에 근거하여 국내 인증 체계에 부합될 수 있도록 건축 구조용 PC 제품의 인증제도의 도입 방향을 이 논문에 제시하였다.

Precast concrete deck through factory production of precast products can minimize construction method and the traffic congestion and can be effective alternative to conventional cast-in-place. In particular, in the case of precast deck, connection details between precast decks are very important because durability and load-bearing performance of structures is greatly affected by them. so conneciotion details to secure constructability and safety, affordability are very important. In this study, a new connection detail on the precast deck connections are proposed and test results comparison from various parametric experiments would be performed to verify the applicability of the proposed technique.

In this research, a total of seven specimens were tested under reversed cyclic loading, controlled by displacement and three times of reversed loads were given at each displacement. The goal of experiments is to identify the seismic and structural performance of pure dry precast concrete beam-column joints using bolt type connection and/or prestressing methods. Two representative results are examined and compared in this paper.

This paper introduce a calculation method for the length of steel and rebar due to load onto the member in large scale structure using precast composite structure system. As result, cost effectiveness of members in large scale structure is procurable by utilizing steel and rebar economically.

This paper presents a half-precast composite concrete slab using a strain-hardening cementitious composites (SHCC). The flexural characteristics of SHCC-RC Composite slab was evaluated with a conventional reinforced concrete slab and the composite slab was excellent in crack control to compare with the reinforced concrete slab.

This paper presents a design process of columns in precast concrete frame building structure constructed by using hollowed precast concrete (HPC) column. An example PC frame building was designed and the structural safety of HPC columns was checked as a form for during slab construction and a composite column for design load after construction based on the previous research.

To strengthen the competitiveness of the domestic precast concrete industry, any legal or institutional measures for a guarantee of quality and safety standards are required. So, the overseas cases for precast concrete certification program were investigated and analyzed to present the new certification program in Korea.

As existing bridges become deteriorated, deck replacement is highly demand. Precast concrete deck system is considered as a effective alternative to in-site concrete deck system in terms of reducing construction period and securing deck quality. In this paper, technology trends in precast deck connections are studied, which is an important factor for securing deck performance. The result shows that studies in precast deck connections are recently increasing drastically and development of new precast deck system is needed.

이 연구에서는 고로슬래그 미분말을 사용한 프리캐스트 보의 전단성능에 대하여 평가하였다. 실험체는 고로슬래그 미분말 치환율에 따라 총 4체의 실험체를 제작하였다. 모든 실험체는 전단경간비 2.5, 보의 폭 200mm, 유효깊이 300mm이며, 3점 가력을 받는 단순보로 계획하였다. 또한 이 연구에서는 실험체의 전단강도를 예측하기 위하여 기존 전단강도 예측식을 이용하여 실험결과와 비교하였으며, 총 89개의 기존 전단 실험결과를 이용하여 실험결과와 비교 분석하였다. 실험결과, 고로슬래그 미분말을 치환한 실험체는 포틀랜드 시멘트만을 사용한 실험체와 비교분석한 결과 유사한 전단성능을 나타내었다.

In this paper, experimental study of composite slab systems was performed. The slab system could minimize reinforcements and improve crack control by applying high-ductile cementitious composites. In the application of the field construction, the construction process of the half-precast system could minimize the formwork of concrete construction.

The objective of this study is to investigate the safety of the slab type precast module. To achieve this, the designed slab type precast module was made using the manufacturing facility for the precast modular superstructure and the flexural performance test was conducted.

In this study, the mock-up test of a girder-type precast module was conducted for evaluated construction applicability. Results of mock-up test, girder type precast module`s process of manufacturing and transport, fabrication, installation was satisfied the construction application.

In recent years, many potholes in asphalt pavement occurred. In order to facilitate the repair, in this study, repair materials with high durability and excellent productivity appropriate for asphalt pre-cast materials was developed. Physical properties test and durability test of various repair materials(SMA, PMA, guss mixtures, water-reactive mixtures) were performed. In order to evaluate the workability at pre-production time of samples using repair materials were made in different shapes and sizes. Finally, after comparing mixtures, water-reactive mixture was selected as repair material. This was verified through several testing.

This study utilizes an equation proposed for the calculation of the lateral-torsional buckling moment of a reinforced concrete beam to evaluate the lateral rollover stability of a precast concrete girder particularly during construction. The result of this study showed the lateral-torsional capacity of a girder significantly decreased with an increase in the initial sweep of the girder. The capacity of a girder with the initial sweep in the order of around two times the PCI tolerance becomes smaller than its ultimate flexural capacity.

Prestressed concrete (PSC) members are readly available in civil engineering applications due to the convenience of construction and easy of quality control in the manufacturing process of the member. Especially, half-depth precast concrete composite slab, which is one of the PSC flexural members is developed recently using the long-line method. The half-depth precast concrete composite slabs are composed of the precast concrete and the in-situ concrete placed at the site. In this paper, we present the results of experimental investigations pertaining to the pretensioning efficiency and the flexural behavior of half-depth precast concrete composite slab which is made of precast PSC manufactured by the long-line method. In the long-line method, the pretensioned precast member is manufactured simultaneously, by tensioning tendons at once. In addition, we suggest the equation that can estimate the flexural strength of half-depth precast concrete composite slab reasonably by considering the effects of rebar embedded in the precast PSC flexural member.

최근, 프리캐스트를 통한 모듈화에 대한 관심으로 인해 교량 및 빌딩 뿐만 아니라, 원전구조물, LNG 가스탱크, 중소형 강합성 구조물 등 특수구조물에도 프리캐스트 모듈화에 대한 연구가 활발하게 이뤄지고 있다. 본 연구에서는 프리캐스트 제작의 시공 및 작업성, 원활한 자재의 조달할 수 있는 방법으로 페로시멘트 (ferrocement)를 바탕으로 한 스틸메쉬로 보강된 모르타르 프리캐스트 패널을 제작하였다. 모르타르는 고강도 및 고유동성을 지니도록 실리카퓸과 고로슬래그의 배합율에 대한 변수연구를 통해 최적의 배합을 선정하였으며, 1,200×600×150mm의 패널을 제작하여 스틸메쉬로 보강한 모르타르 시편과 일반 철근콘크리트 시편을 보강비 2%와 4%로 각각 제작하였다. 제작된 스틸메쉬로 보강한 모르타르의 프리캐스트 모듈화의 적용 가능성을 판단하기 위하여 기본적인 재료물성실험과 자유건조수축실험을 수행하였으며, 선하중으로 하중을 재하하여 3점 휨 시험으로 스틸메쉬로 보강한 모르타르의 구조성능을 검토하였다. 실험결과를 통해, 스틸메쉬로 보강된 모르타르 프리캐스트 패널은 높은 휨성능 및 연성효과가 있으나, 4%로 보강된 스틸메쉬 모르타르 프리캐스트 패널은 전단보강에 대한 고려가 필요하다고 판단되며, 이에 대한 조치가 이루어진다면 프리캐스트 모듈화 부재로 적용이 가능하다고 판단된다.