• 한국전산구조공학회논문집
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• 제28권2호
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• pp.131-138
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• 2015

본 논문에서는 도로교 설계기준이 개편됨에 따라 변화된 활하중과 설계식의 검토를 하려한다. 이를 위해 강합성 플레이트 거더교와 PSC 거더교를 이용한 두 예제를 살펴본다. 기존 도로교설계기준 하중과 AASHTO LRFD 하중 그리고 새로 개편된 도로교설계기준 2015 한계상태설계법에 나온 하중을 적용하여 횡분배 계수법과 유한요소 격자해석을 통해 구한 포락선을 비교 검토한다. 또한 강합성 플레이트 거더교의 경우 중앙지간의 길이 변화에 대한 검토를 하고, PSC 거더교의 경우에는 가로보의 개수와 경간의 개수, 그리고 각 경간장의 변화를 주어 각각 그 차이점을 분석한다.

• Structural Engineering and Mechanics
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• 제29권2호
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• pp.135-154
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• 2008

The moving vehicle loads on a bridge deck is one of the most important live loads of bridges. They should be understood, monitored and controlled before the bridge design as well as when the bridge is open for traffic. A MOM-based algorithm (MOMA) is proposed for identifying the timevarying moving vehicle loads from the responses of bridge deck in this paper. It aims at an acceptable solution to the ill-conditioning problem that often exists in the inverse problem of moving force identification. The moving vehicle loads are described as a combination of whole basis functions, such as orthogonal Legendre polynomials or Fourier series, and further estimated by solving the new system equations developed with the basis functions. A number of responses have been combined, some numerical simulations on single axle, two axle and multiple-axle loads, being either constant or timevarying, have been carried out and compared with the existing time domain method (TDM) in this paper. The illustrated results show that the MOMA has higher identification accuracy and robust noise immunity as well as producing an acceptable solution to ill-conditioning cases to some extent when it is used to identify the moving force from bridge responses.

• 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.

• 한국지진공학회논문집
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• 제15권2호
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• pp.11-22
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• 2011

개발된 완전 조립식 교량 하부구조에 대한 설계비교와 비선형 해석을 수행하였다. 조립식 교량 하부구조는 현행설계법과 하중저항계수설계법으로 설계하였다. 설계시에는 현 도로교설계기준에 규정된 DB-24 및 DL-24 설계활하중을 적용하였다. 이 연구는 비선형 유한요소해석을 통해서 완전 조립식 교량 하부구조의 현행 설계법인 KHBD (2005)와 AASHTO-LRFD (2007)를 평가하였다. 사용된 프로그램은 철근콘크리트 구조물의 해석을 위한 RCAHEST이다.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1992년도 봄 학술발표회 논문집
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• pp.126-133
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• 1992

The structural soundness of bridges is mainly damaged by overloaded heavy vehicles. The increasing volumes of overloaded heavy vehicles has been indicated as serious state. As results several countries have revised their bridge load codes. However, because of variety of truck types and their weights it is difficult to develop rational standard truck loads. In addition the common practice that only one design configuration of standard truck is adopted to design variety of bridges causes further difficulties. The objective of the study is to investigate the statistical characteristics of vehicle loadings based on survey data col looted, in which some major factors, such as vehicle configurations, vehicle freights, traffic modes, etc. are incorporated.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2002년도 춘계학술대회 논문집
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• pp.179-184
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• 2002

For the development of the practical design and analysis scheme of a bridge connecting to the typical VLFS, relevant design criteria and theory and techniques are studied and numerical analysis for the verification of the structural safety of the bridge are carried out. For the design of a typical steel bridge, characteristics of proper type bridge are reviewed and the requirements fur the bridge of this kind are studied as well as the environmental loads. By using the design spiral technique, several alternatives are investigated and an efficient type of a bridge is initially designed. Structural idealization is performed to make overall structural analysis first, and the structural behaviors of the proposed bridge in the given loading condition are evaluated. Through this study a bridge is finally proposed and it is found that this one works well for the connecting function of the bridge.

• 한국강구조학회 논문집
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• 제19권1호
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• pp.87-98
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• 2007

일반적으로 가교량은 주형와 강재교각이 강결 연결된 강재 라멘구조를 형성하고 있다. 강재 라멘구조의 경우, 작용하는 하중에 의해 축력 및 휨을 받는 부재/축력 및 휨을 동시에 받는 부재가 발생한다. 본 연구에서는 이러한 부재에 대해서 시스템 좌굴해석을 통하여 가교량 주요부재의 유효길이를 산정하고 이를 이용하여 안정성 해석을 수행한다. 이를 위하여 실제 설계/시공될 수 있는 가교의 6가지 유형을 선택하고, 고정하중, 온도하중 그리고, 활하중조합에 대한 3차원 좌굴설계를 실시한다. 결과적으로 6가지 가교에 대한 사례연구를 통하여 주형 및 교각부의 유효길이 산정법, 3차원 좌굴모드에 대한 고찰, 그리고 2차해석의 효용을 조사한다.

• KCI Concrete Journal
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• 제14권1호
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• pp.36-42
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• 2002

Flexural behaviors of the two typical precast beam sections (inverted tee and rectangular) for buildings were investigated and compared. The height of web in the inverted tee beam was generally less than half of beam depth to be adapted to that of the nib in the ends of double-tee where the total building height limited considerably. The inverted-tee beams were designed for a parking live load - 500kgf/$m^2$ and a market - 1,200kgf/$m^2$ from the currently used typical shape of a domestic building site in Korea. The area and bottom dimension of rectangular beams were the same as those of inverted tee beams. These woo beams were also reinforced with a similar strength. following results were obtained from the studies above; 1) the rectangular beam is simpler in production, transportation, and erection, and more economic than the inverted tee beam in the construction test for these two beams with a same dimension and a similar strength, 2) all of the beams considered in the tests were generally failed in values close to those of the strength requirements in ACI Provisions. The ratios of test result to calculated value are averaged to 1.04. One rectangular and one inverted tee beams failed in a value only 2-3％ larger than the estimated volue of the Strength Design Methool the results of the Strain Compatibility Method wire slightly more accurate than those of the Strength Design Method, 4) the maximum deflections of all of the beams under the full service loads were less than those of the allowable limit in ACI Code Provisions. The rectangular beams experienced more deflection then inverted tee in the same loading condition and failed with more deflection, and 5) the rectangular and inverted tee beams showed good performances under the condition of service and ultimate loads. However, one inverted tee beams with fm span developed an initial flexural crackings under 88％ of the full service load even though they designed to satisfy the ACI tensile stress limit provisions.

• 한국구조물진단유지관리공학회 논문집
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• 제18권3호
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• pp.93-100
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• 2014

본 연구는 교량의 상시계측자료인 고유진동수 및 고유모드를 기준으로 계측기반모델을 구성하고, 구조해석을 수행하여 교량 공용상태에서 사장케이블 장력평가를 수행하였다. 케이블 설치 위치에 따라 하중유형별 케이블 장력이 다르다는 것을 알 수 있다. 고정하중과 활하중에 의한 케이블 계측장력은 케이블 설치위치에 따라 차이가 크지 않으나 설계하중을 적용한 해석결과보다 큰 값을 나타낸다. 계측기반모델에 대한 케이블장력분포는, 설계모델에 대한 장력보다 크지만, 계측장력과 유사한 분포를 나타낸다. 그러므로 장기거동을 고려하여 사장교 케이블설계는 계측기반모델의 해석결과를 반영할 필요가 있다. 이를 위하여 많은 계측자료를 이용한 장기거동 분석연구가 요구된다.

• 한국안전학회지
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• 제14권4호
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• pp.142-147
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• 1999

Formwork is a temporary structure that supports its own weight and that of the freshly placed concrete as well as construction live loads including materials, equipments, and workmen. In designing and building formwork, the contractor should plan for economical construction without sacrificing quality or safety. But these temporary structures sometimes collapse during the concrete placing. Among the accidents and failures that occur during concrete construction, many are formwork failures, which usually happen at the time concrete is being placed. Generally some unexpected events cause one member to give way, then others become overloaded or misaligned and the whole formwork structure collapses. In this study, formwork failure events from 1994 to 1997 are analyzed using the structural analysis program. So the causes of the respective formwork failure are explored. Therefore, the present study provides a firm base to design the temporary structures such as formwork.