• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2000년도 봄 학술발표회논문집
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• pp.389-396
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• 2000

A three-dimensional finite element dynamic analysis was conducted to evaluate the effects of reducing cross beams from a simply supported straight P.S.C girder bridge. Two analyses were performed on the P.S.C girder bridge; one with 7 cross beams which is commonly used as current standard, and the other with 3 cross beams. A frequency analysis was conducted first in order to establish the dynamic characteristics of the bridge and determine an appropriate time step to use in the time history analyses. To assess the function and effectiveness of the cross beams, time history analysis was conducted for aforementioned two analysis cases. In the analysis, the complete model was subjected to a loading condition corresponding to the one passing truck loading. Several results of deflection, bending moment and shear forces were compared for two cases. From the analysis results, reduction of cross beams was found to have only a minimum effect on the response of the bridge. The maximum deck slab bending moment was found to decrease. This decrease should result in smaller flexural crack widths in the deck slab, which may lead to an improved deck performance.

• 한국구조물진단유지관리공학회 논문집
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• 제3권4호
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• pp.139-144
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• 1999

Based on the recent developments of the reliability-based structural analysis and design as well as the extending knowledge on the probabiliistic characteristics of load and resistances, the probability based design criteria have been successfully developed for many standards. Since the probabilistic characteristics depend highly on the local load and resistances, it is recognized to develop the design criterion compatible with domestic requirements. The existing optimum design methods, which are generally based on the structural theory and certain engineering experience, do not realistically consider the uncertainties of load and resistances and the basic reliability concepts. This study is directed to propose a optimum design based Expected Total Cost Minimization on P.S.C Box Girder Bridge system which could possibly replace optimum design based traditional provisions of the current code, based on the Neldel-Mead Method reliability theory.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2008년도 정기학술발표대회 논문집
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• pp.197-201
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• 2008

국내 도로건설사업은 평균 단가 기준으로 개략공사비를 산정한다. 도로의 기초자료를 갱신함으로써 평균 단가를 수정하고 있으나 공사 특성을 전부 반영하기에는 미흡한 실정이다. 설계 진행단계에서 설계 대안을 평가하는데 활용할 수 있는 공사비 예측모델의 필요성이 제기되는 가운데 대표공정을 통해 표준물량을 산출하고 개략공사비 산정모델개발을 통해 실질적인 공사비 예측이 가능한 모델을 개발하고자 한다. 본 연구에서는 Prestressed Concrete Box Girder Bridge의 상부공사를 중심으로 연구를 수행하며 $2000{\sim}2007$년 사이에 수행되었던 구조물공 41건에 대한 기초자료를 수집하고 토목공사 수량산출기준에 의한 내역서를 기반으로 Grouping을 실시하여 대표적 특수교량인 ILM(Incremental Launching Method), MSS(Movable Scaffolding System), FSM(Full Staging Method), 그리고 FCM(Free Cantilever Method)등 교량 형식별로 총공사비에서 공사비 비중 및 해당 공종에서의 중요도가 높은 항목을 중심으로 설계 초기단계에서 가용한 정보 수준을 고려하여 대표공종 선정한다. 교량 형식별 선정된 대표공종을 살펴보면 P.S.C 강재설치 및 긴장작업/P.S.C BOX/자재대 및 자재운반비/철근가공 및 조립/증기양생/콘크리트 타설/거푸집/교면 방수/동바리 등 교량형식별 특수성을 제외하면 대표공종들이 순공사비에서 차지하는 비중이 비슷함을 알 수 있다. 공종들이 총공사비에서 차지하는 비율은 ILM(99.47%)/ MSS(99.22%)/ FSM(98.18%)/ FCM(98.12%)로 나타났다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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• pp.1125-1130
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• 2004

The prestressed concrete girder bridges have been used widely at the domestic national road as well as highway because it is great in the functional and economical efficiency. Also it has the advantage of convenience of design and construction due to being given standard sections. However it could be easily verified that a standard section of P.S.C girder is excessive design, which has much more redundancy than is necessary against design loads. Thus, in this paper the formulation of the optimum design for PSC girder railway bridge is suggested and dominant design variables and constraints are inquired as performing the optimum design. The objective is adopted as total cost of PSC girder bridge ,and in order to effective optimum design, design variables are formulated as PSC girder section dimension and girder space as well. And constraints are formulated according to Korean railway design specification and considering construction-ability such as PS anchorage and girder space. Using the proposed optimum design system, optimum PSC girder bridge design has been performed. And from the results of analysis it is suggested to denote the optimum section which satisfies the structural safety ,and economical efficiency all together.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2001년도 가을 학술발표회 논문집
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• pp.219-226
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• 2001

In general, engineers have to consider a variety of factors in design of a structure. For this reason, it was difficult to make a design program up to now. But the rapid development of hardware and software turns it into a possibile one with considering complex factors and designing simple structures. When we use the design program including structural analysis, we can save time and cost to make calculations; report and drawing. In addition, the design program was developed to reduce the man made errors. Therefore, in this study, we try to develope the design program of the superstructure of P.S.C girder bridge and abutment. This program will provide engineers with time that they can spend on a creative and efficiency task for development of design.

• 한국전산구조공학회논문집
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• 제14권1호
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• pp.43-55
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• 2001

본 논문에서는 현행 표준적인 P.S.C거더 교량의 적정 가로보 수를 위한 매개변수 연구를 수행하였다. 교량의 길이는 P.S.C거더교로서 국내에서 가장 흔히 사용되는 30m의 단순교를 채택하였다. 교량의 해석방법으로는 상부의 슬래브와 거더를 효율적으로 모델링하기 위하여 정밀해석법인 유한요소법을 사용하였다. 본 연구에서 사용된 매개변수로는 크게 두 가지로 분류되는데, 하나는 사용된 가로보의 개수이고 다른 하나는 교량의 사각(Skew)이다. 상부 슬래브는 쉘 요소와 빔 요소를 연결하는데 효율적인 회전자유도를 가지는 쉘 요소로 모델링 하였다. 슬래브와 거더의 중심축이 이격되어 있는 문제를 정확히 고려하기 위하여 편심보 요소를 사용하였다. 해석 모델은 가로보가 각각 7,5,3개 있는 경우를 선정하였다. 이러한 조건하에서 정적 해석을 수행하여 최대 휨모멘트, 전단력, 비틀림 모멘트값을 구하여 현행 시방서에서 규정된 극한치를 만족하는지 검토하였다. 검토결과 현재 사용되고 있는 P.S.C거더 교량에서의 가로보 개수는 과다한 것으로 판단되며 경제적인 설계를 위하여 가로보의 개수를 줄일 수 있을 것으로 제안하였다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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• pp.934-939
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• 2004

The Korea high-speed rail, based on the French design. It also implements new concept to increase the strength of bridge deck by adding an impact factor (dynamic intensity factor) in static load. In order to assure the dynamic stability, SYSTRA and Jeseph Penzien, a professor in CEC (the US) conducted a dynamic stability review on design phase. Analyzing the review results, they developed design criteria for dynamic behavior. This study deal with operating PSC box GIRDER equipped with measurement equipment or measured data of Seoul $\∼$ Taejeon, P.S.C BOX GIRDER bridge and steel comsition bridge equipped with measurement equipment based on structual knowledge about configuration of measuring sensor, response analysis of structure when train runs was performed by using measured data of PSC box girder to directly compare with design criteria. moreover, the dynamic stability with comparison of high-speed rail construction criteria was reviewed and analyzed based on historical records.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2001년도 추계학술대회 논문집
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• pp.293-298
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• 2001

2span continuous Prestressed concrete girder railway bridges, span length 21m, 25m, 30m, 35m, that down-up method is applied and that designed to satisfy service load in accordance with design criteria of railway bridge can be dropped in their hight compared with existing simply supported prestressed concrete girder railway bridges. Continuous bridges result in guaranteeing safety against bending behavior by loading the practical railway moving load with each velocity. But the natural frequency of span length 21m is estimated not to satisfy recommended limitation of UIC 776-1R..

• 대한토목학회논문집
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• 제33권2호
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• pp.781-790
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• 2013

본 연구에서는 평균건설단가를 적용하여 개략 공사비를 산출하는 기존 방식에서 벗어나 대표공종을 이용한 입력변수 도출 모델을 구축하여 기본설계단계에서 고려되어지는 여러 입력변수들을 활용하여 P.S.C(Prestressed Concrete) Box Girder 교량에서 널리 활용되고 있는 I.L.M(Incremental Launching Method) 공법에 연구 모델을 적용하고자 한다. 2000년부터 설계된 공사비 데이터와 설계자료 등을 분석하여 상부공사 중 총 공사비대비 누적비율 95%이상을 차지하는 공종을 대표공종으로 도출하였다. 각 대표공종의 하위공종에 대한 내역 분기를 실시하여 각 항목들의 Database를 구축하였다. 본 연구에서는 다각적인 측면에서 개략공사비 산정 모델을 개발 및 제시하였으며, 사용자 입장에서 보다 쉽게 접근할 수 있도록 대표공종을 기초로 단위물량을 사용한 개략공사비 산정모델(I)과 상관성이 높은 입력변수를 선택한 개략공사비 산정모델(II)과 상관계수 0.6이상의 입력변수들을 모두 포함하는 다중회귀분석을 통한 개략공사비 산정모델(III)을 제시한다. 실제 총공사비와 본 연구에서 제시하는 개략공사비 산정모델들을 비교하고, 신뢰성을 검증함으로써 현재 국내에서 사용되는 산정방법에 비해 정밀도 측면에서 효율적인 공사비 관리방법을 제시한다.

• Computers and Concrete
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• 제21권3호
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• pp.269-278
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• 2018

In this paper, two methods M1 and M2 to determine long-term deflection through finite element analyses including the effect of creep and relaxation are proposed and demonstrated for a PSC box-girder. In both the methods, the effect of creep is accounted by different models from international standards viz., ACI-209R-92, CEB MC 90-99, B3 and GL2000. In M1, prestress losses due to creep and relaxation and age adjusted effective modulus are estimated through different models and have been used in finite element (FE) analyses for individual time steps. In M2, effects of creep and relaxation are implemented through the features of FE program and the time dependent analyses are carried out in single step. Variations in time-dependent strains, prestress losses, stresses and deflections of the PSC box-girder bridge through M1 and M2 are studied. For the PSC girder camber obtained from both M1 and M2 are lesser than simple bending theory based calculations, this shows that the camber is overestimated by simple bending theory which may lead to non-conservative design. It is also observed that stresses obtained from FEM for bottom fibre are lesser than the stresses obtained from bending theory at transfer for the PSC girder which may lead to non-conservative estimates.