• 한국안전학회지
• /
• 제28권5호
• /
• pp.41-48
• /
• 2013

This paper is intended to provide the background information and justification for Korean highway bridge design code(limit state design)(2012). Limit state design method calculates reliability index and probability of failure through the analysis of the reliability of the experimental database. It has become possible to perform the economical and consistent design by evaluating the safety of a structure quantitatively. In this paper, we used the design specifications of RC slab bridge of superstructure form of Road Design Manual in Part 5 bridge built in highway bridge. This study conducted structural analysis using the method of frame structure theory, design and analysis of bridge by limit state design method, the design code including various standards and Load model applied Korean highway bridge design code limit state design(KHBDC;2012). As a result, it analyzed the effect of safety through comparison. Showing effect of improvement the safety factor and comparing the value of the result, it is determined to be capable of economical design and safety. Furthermore, limit state design method was able to determine many redundant force of cross-section compared with existing design method. It is determined that it can reduce the overall amount because of the reduction of the cross-section and girder depth.

• 한국강구조학회 논문집
• /
• 제16권5호통권72호
• /
• pp.587-598
• /
• 2004

본 연구에서는 합성보의 전체 춤을 절감할 수 있도록 속 빈 프리캐스트 콘크리트 슬래브를 철골보의 춤내에 삽입하여 일체화함으로써 철골조 고층건물에서 층고를 최소화 할 수 있는 이른바 "슬림플로어"공법에 대한 연구를 수행하였다. 본 연구는 콘크리트에 매입된 비대칭 철골보를 가지는 불완전 합성 슬림플로어 시스템의 휨 거동에 관한 것이다. 총 10개의 실대형 실험체를 철골보 춤, 속빈 프리캐스트 콘크리트 슬래브 춤, 슬래브 유효폭, 및 콘크리트 슬래브의 지지방식 별로 제작하여 실험을 수행하였다. 실험결과, 매입형 합성보의 경우, 별도의 전단연결재를 설치하지 않아도 자체가 가지고 있는 기계적 화학적 부착응력으로 인해 완전합성보에 비해서 0.48~0.98의 전단합성비를 나타내었다.

• KIEAE Journal
• /
• 제7권6호
• /
• pp.113-118
• /
• 2007

The composite beam adopted in the study was designed to reduce the floor height as well as to embed the top flange of steel frame into the slab that will enable to avoid applying the fire-resistant coating and to unify the joint method with a steel frame-type. As the steel frame and bottom concrete of the beam is pre-fabricated at the factory it could reduce the overall schedule at the jobsite. Applying such composite beam system to the work is expected to provide the efficient and enhanced performance, given the current tendency of the building construction that tends to be getting higher, larger and dense. The study focused on combining the composite beam with various column systems in a bid to propose the details thereof. A desirable composite girder can be adopted depending on site conditions through the evaluation of various beam and jointing approaches. Among the column systems applied to the study are steel column, SRC column, RC-PC column and RC column. The ways of combining with the columns addressed in the study were categorized into the rigid joint, pin joint, steel frame joint and bracket type joint. Besides, the instruction for site fabrication of beam-column was added in an effort to help set up the site fabrication procedures.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2013년도 춘계 학술논문 발표대회
• /
• pp.14-15
• /
• 2013

Green Frame is precast concrete column-beam structure. There are three types on column connection. The coupler type which is one of the three, need to be improved because of unstability caused by pre-installation of column before casting the slab, and quality deterioration caused by lack of workspace. Therefore, in this study, new coupler connection type with thread rebar is suggested. The result of this study shall be used for the efficiency analysis of the new coupler connection.

• 한국강구조학회 논문집
• /
• 제13권1호
• /
• pp.29-40
• /
• 2001

상업건축물에서 사용이 증가하고 있는 철골조 건물은 일반적으로 콘크리트 바닥 슬래브와 함께 합성거동하도록 설계된다. 현제 "합성 구조"가 사용성 측면에서 경제적이고 작업성이 좋으며, 시공상의 편의성 등의 장점이 있다는 것은 일반화된 사실이지만, 자체의 춤이 깊기 때문에 철골조 아파트에 적용되기에는 어려움이 있다. 따라서 본 연구는 이러한 합성의 전체 춤을 절감할 수 있는 반슬림플로어 시스템을 개발하였다. 본 시스템은 철골보 춤내에 콘크리트 슬래브를 삽입하여 일체화함으로써 철골조 고층건물에서 층고를 최소화 할 수 있는 공법이다. 실험은 12개의 합성슬래브 실험체를 데크현상, 슬래브폭, 스터드볼트의 유무와 콘크리트 토핑두께를 변수로하여 휨성능을 평가하였다.

• 한국강구조학회 논문집
• /
• 제19권2호
• /
• pp.233-245
• /
• 2007

AASHTO Standard의 하중분배계수식은 지간과 주형간격이 클수록 안전측으로 나타나지만, 지간과 주형간격이 작으면 비안전측임을 기존의 유한요소 연구에서 밝혀졌다. AASHTO LRFD는 주형간격, 지간, 바닥판 두께, 그리고 종방향 강성에 따른 분배계수식을 규정하고는 있으나, 이 식은 초기에 알려지지 않은 종방향 강성 때문에 정확한 하중분배계수 값을 결정하기 위해서는 반복절차가 요구되어진다. 따라서 본 연구에서는 2경간 연속 I-형교의 내측 및 외측주형에 대하여 반복설계 과정을 필요로 하지 않는 하중분배계수 간략식을 제안한다. 주형간격, 주형길이, 바닥판 두께, 바닥판 폭, 그리고 브레이싱의 간격 및 크기의 영향을 조사하기 위하여 유한요소법을 사용하였다. GTSTRUDL을 사용하여 교량 상부구조를 편심 보모델로 이상화 하였으며, 바닥판은 쉘요소, 거더는 보요소, 그리고 이 요소들의 합성거동을 위하여 강절링크로 연결하였다. 이 해석으로부터 얻은 분배계수를 AASHTO Standard와 LRFD 방법과 비교하였으며, 다른 매개변수들에 비해 거더간격, 지간, 그리고 바닥판 두께는 분배계수에 미치는 영향이 크게 나타났다. 내측주형에서 LRFD의 분배계수는 대부분의 경우에 안전측으로 나타났지만, 외측주형에서는 지간이 길 경우 비안전측으로 나타났다. 또한, 회귀분석을 수행하여 하중분배계수 간략식을 개발하였으며, 이 식에 의한 하중분배계수는 유한요소결과 보다는 항상 안전측이면서, AASHTO LRFD 보다는 일반적으로 작게 나타났다. 제안된 간략식은 2경간 연속 I-형교에 대한 실제 하중분배계수 산정에서 교량설계자들에게 도움을 줄 것이다.

• Steel and Composite Structures
• /
• 제20권6호
• /
• pp.1237-1257
• /
• 2016

The paper concerns analysis of effects of shrinkage of slab concrete in a steel-concrete composite deck of a through truss bridge span. Attention is paid to the shrinkage alongside the span, i.e., transverse to steel-concrete composite cross-beams. So far this aspect has not been given much attention in spite of the fact that it affects not only steel-concrete decks of bridges but also steel-concrete floors of steel frame building structures. For the problem analysis a two-dimensional model is created. An analytical method is presented in detail. A set of linear equations is built to compute axial forces in members of truss girder flange and transverse shear forces in steel-concrete composite beams. Finally a case study is shown: test loading of twin railway truss bridge spans is described, verified FEM model of the spans is presented and computational results of FEM and the analytical method are compared. Conclusions concerning applicability of the presented analytical method to practical design are drawn. The presented analytical method provides satisfactory accuracy of results in comparison with the verified FEM model.

• Structural Engineering and Mechanics
• /
• 제49권1호
• /
• pp.95-110
• /
• 2014

The study deals with physical modeling of space frame-pile foundation and soil system using finite element models. The superstructure frame is analyzed using complete three-dimensional finite element method where the component of the frame such as slab, beam and columns are descretized using 20 node isoparametric continuum elements. Initially, the frame is analyzed assuming the fixed column bases. Later the pile foundation is worked out separately wherein the simplified models of finite elements such as beam and plate element are used for pile and pile cap, respectively. The non-linear behaviour of soil mass is incorporated by idealizing the soil as non-linear springs using p-y curve along the lines similar to that by Georgiadis et al. (1992). For analysis of pile foundation, the non-linearity of soil via p-y curve approach is incorporated using the incremental approach. The interaction analysis is conducted for the parametric study. The non-linearity of soil is further incorporated using iterative approach, i.e., secant modulus approach, in the interaction analysis. The effect the various parameters of the pile foundation such as spacing in a group and configuration of the pile group is evaluated on the response of superstructure owing to non-linearity of the soil. The response included the displacement at the top of the frame and bending moment in columns. The non-linearity of soil increases the top displacement in the range of 7.8%-16.7%. However, its effect is found very marginal on the absolute maximum moment in columns. The hogging moment decreases by 0.005% while sagging moment increases by 0.02%.

• Steel and Composite Structures
• /
• 제11권2호
• /
• pp.149-168
• /
• 2011

This paper presents a computational study of column loss scenarios for typical multi-story steel buildings with perimeter moment frames and composite steel-concrete floors. Two prototype buildings (three-story and ten-story) were represented using three-dimensional nonlinear finite element models and explicit dynamic analysis was used to simulate instantaneous loss of a first-story column. Twelve individual column loss scenarios were investigated in the three-story building and four in the ten-story building. This study provides insight into: three-dimensional load redistribution patterns; demands on the steel deck, concrete slab, connections and members; and the impact of framing configuration, building height and column loss location. In the dynamic simulations, demands were least severe for perimeter columns within a moment frame, but the structures also exhibited significant load redistribution for interior column loss scenarios that had no moment connectivity. Composite action was observed to be an important load redistribution mechanism following column loss and the concrete slab and steel deck were subjected to high localized stresses as a result of the composite action. In general, the steel buildings that were evaluated in this study demonstrated appreciable robustness.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2009년도 추계 학술논문 발표대회
• /
• pp.247-252
• /
• 2009

With the increasing use of tower cranes higher than free standing height, the importance of lateral support is also growing. Since the fall of 43 tower cranes hit by the last typhoon 'Mami' in 2003, regulations and concerns about safety of construction equipment have increased and construction laws regarding lateral support have been strengthened. In Korea, where there are many large-scale apartment housing construction works with the development of new towns, Rope Guying is a more economical construction method than Wall Brace which fixes building structure like building wall and slab. The safety of this Rope Guying is not verified and many construction works are still carried out based on the experience of site managers. There has been no case of construction work where frame and measurements are applied. The objective of this study is to examine the safety of Rope Guying method and ensure the effective implementation of equipment and prevention of disasters.