• Proceedings of the Computational Structural Engineering Institute Conference
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• 2010.04a
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• pp.742-745
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• 2010

본 논문은 초고층구조물의 해석방법으로 탄성변형과 아울러 시간의존성을 가진 크리프와 건조수축에 의한 비탄성변형을 고려한 비선형 시공단계 해석법을 제시한다. 기존의 초고층구조물 해석에서 주로 행하는 기둥 축소량 해석은 실무자의 경험과 프로그램을 통한 간략화에 맞추어져 있다. 이는 실제 시공 시 발생하는 구조해석 요소들을 충분히 반영하지 못하여 계산 값과 실제 값 사이에 오차가 발생된다. 비선형 시공단계 해석은 실제 시공 때 발생되는 해석변수들을 고려한 단계별 해석의 수행이 가능하며, 시간의 의존성을 가진 creep과 shrinkage의 효과를 함께 고려하여 일괄해석의 문제점을 구조해석 단계에서 실제상황에 가까운 해석을 가능하게 할 수 있다. 이를 위해 시공단계해석이 가능한 범용 프로그램을 이용한 50층 규모의 3차원 골조 프레임 모델 예제 해석을 통하여 기존 해석법들과의 비교, 분석으로 시간의 의존성을 고려한 시공단계해석의 필요성을 제시한다. 본 논문에는 범용프로그램인 SAP2000(ver.14)와 CEB-FIP모델 코드를 사용 하였다.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2010.04a
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• pp.263-266
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• 2010

비정형 형상의 초고층 건물이 증가함에 따라, 설계 시공 계획 단계에서의 시공 중 건물의 구조적 안정성 검토가 핵심 사항으로 부각되고 있다. 시공 중 비정형 초고층 건물의 안정성을 확보하기 위해서는, 횡력저항시스템이 완전히 형성되기 전 구조체 자중의 불균형 분포에 의해 발생하는 수직부재의 불균등 축소, 골조의 기울어짐 혹은 횡변위 등이 시공단계해석에 의하여 검토되어야 하며, 시공단계해석은 구조건전성모니터링, 시공 보정 프로그램, 시공계획 수립 등과 체계적으로 결합되어 진행되어야 한다. 이 논문은 시공 중 비정형 초고층 건물의 구조 안정성 검토를 위하여, 실제 비정형 초고층 프로젝트에 시공단계해석을 적용하였으며, 시공 중 초고층 건물의 안정성 확보를 위한 주요 검토 항목 및 방법을 제시하였다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.6A
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• pp.881-891
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• 2008

The purpose of the present study is to investigate the influence of seasonal temperature variation on the thermal stresses in roller compacted concrete dam(RCD) structures. Using the finite element code, DIANA performs 2-D transient temperature and resultant stress analysis for RCD. Time variability of the mesh geometry is considered in order to simulate successive phases of the structure's construction. The main analysis variables are construction sequence, concrete temperature and ambient temperature. The results show principal tensile stress of hot-weathering concrete is higher than that of cold-weathering concrete. In some case the index of thermal cracking excesses 1.0, RCD also needs thermal management on placing temperature according to weather condition.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.117-120
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• 2008

Recently, according to the increasement of high-rise building construction and domestic situation, requirements of rapid cycle construction are increasing. For more economical and rapid cycle construction, it is required to reduce formwork cost. So formwork have to be stripped as soon as possible. But as fresh concrete is loaded with construction load, it is likely that the structure will have problems with safety and serviceability. To reduce construction cycle economically, safety and serviceability of structure against construction load have to be considered. But as behavior of structure under construction is so complicated, behavior of structure has to be investigated according to construction stage. Therefore, through field instrumentation of apartment, behavior of structure under construction was analyzed.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.12 no.2
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• pp.171-184
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• 1999

이 논문은 시공단계를 고려한 콘크리트 프레임 구조물의 거동 해석을 다루고 있다. 고층건물의 경우 하루에 시공이 완료되지 않으므로 각 시공단계에 따라 콘크리트의 시간의존적 현상은 다르게 발생된다. 이를 위하여 이 논문에서는 일반적인 프레임 해석기법에 콘크리트의 시간의존적 특성을 고려하였다. 이 연구에 도입된 해석기법은 단면을 가상의 층으로 나누고 각층은 일축상태로 가정한 적층단면을 사용하였다. 요소는 평면 보요소를 사용하였으며 강성행렬은 변위법을 바탕으로 유도하였고 전체적인 구조해석은 비선형 구조해석 방법의 하나인 복합법을 사용하였다. 콘크리트의 시간의존적 특성을 고려하기 위하여 단면의 각 층에서 크리프와 건조수축에 의한 변형률을 계산하였으며 크리프는 크리프 Compliance의 전개에 기본을 둔 1차 순환적 단계 알고리즘을 사용하였다. 끝으로 이 연구에서 제안된 해석모델을 이용하여 프레임해석 및 기둥축소에 관한 예제를 해석하였다.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.5-12
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• 2008

The construction of Pusan National University Yangsan Hospital is a new construction of a medical town in Yangsan. It is a case that CMr participated in the project from planning to post-completion. It shows an actual proof of Construction Management business applied CM by each phase. In this case, CMr selected the design-build contractor in the planning phase and technically performed CM businesses in every single phase such as design and construction schedule management regarding application of Fast Track technique, procurement management and contract administration in phases based on the Fast-tract; technique, design review, VE in the design phase, change order management in the construction phase and operating and maintenance in the post-construction phase. This study would go far toward applying CM to Mega Turnkey projects by analyzing the problems of CMr's practical application to the project and providing guidelines for effective and efficient CM business implementation especially in the Turnkey projects.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.265-268
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• 2008

In this paper behavior of U-Channel Bridge (UCB) and the slab design considering construction sequence was studied. The segments of UCB are produced in the factory and transported to the site by trailers, and the segments are fabricated in the construction field. In this sequence the supporting conditions are changed. Four steps that were the segment precasting step, the segment carrying step, the segment placed on the erection beam step, and the completion step were chosen by supporting condition. In each step model using the frame and plate elements was proposed and structural analysis was performed. Four construction steps were to be considered in the process of slab analysis. The design method of slab was proposed considering construction sequence.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.5
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• pp.96-103
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• 2019

Middle-rise reinforced concrete residential buildings account for a large portion of the Korea, and structural performance analysis are needed for problems that could occur during the construction of such buildings. Thus, a middle-rise reinforced concrete residential building with 25 stories are selected as a sample model for structural performance analysis. The structural analyses are performed by dividing a sample model into the construction stage models of the 5th, 10th, 15th, 20th and 25th floors and the completion stage models with the design completed. For the comparisons of structural performances, Eigenvalue analysis results and lateral-load-resisting capabilities and structural design performances of structural members are analyzed. As a result of analyses, it was confirmed that both the construction and completion stage do not exceed KBC criteria limits at the lateral displacement and story drift ratio, and structural design performances of structural members confirm structural safety in all components except for some members of the wall. Therefore, it was concluded that if structural stability is obtained during the completion stage of a middle-rise reinforced concrete residential building, structural stability is secured under construction.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2010.04a
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• pp.297-300
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• 2010

본 논문에서는 일반적인 해석, 시공단계를 고려한 해석, 시공단계와 장기거동을 고려한 해석의 3가지 해석방법을 사용하여 수평부재의 설계에 적합한 해석방법을 제안하였다. 80층의 2D 구조모델에 3가지 해석방법을 적용하여 각 해석방법에 따라 부등축소량, 수직부재에 작용하는 축력, 수평부재의 단부에 작용하는 내력의 해석결과를 얻어 비교하였다. 또한 부재의 내부에서 철근과 콘크리트의 하중분담율의 시간에 따른 변화양상을 알아보았다. 해석결과 시공단계에 의한 영향은 수평부재에 작용하는 축력과 부등축소량 예측, 부재 내력 해석에 있어서 반드시 고려되어야 함을 알 수 있었다. 장기거동의 효과는 기둥축소에는 크게 영향을 미치지만 수직부재의 축력, 수평부재의 내력에는 변형만큼의 영향은 보이지 않는다. 시공시의 보정량을 결정하기 위해서는 장기거동이 반드시 고려되어야 하지만 부재의 단면설계의 목적으로는 제외되어도 무방할 것으로 판단된다.

• Journal of the Korea institute for structural maintenance and inspection
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• v.14 no.2
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• pp.97-105
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• 2010

The displacements of steel deck bridge due to construction step are measured, and three dimensional analysis with full modeling is carried out to compare with the measured results. Three dimensional structural analyses considering construction step by large block construction method are accomplished with verified model. The conclusions are as follows. 1. Comparing the data of grid analysis with the result of 3D full modeling in steel deck bridge, the design method using grid analysis has a limit for describing the displacements of curved bridge. The analysis of 3D full modeling has been proved as more accurate method. The differentiation of results in two methods is about 10%~20%. 2. It is verified that the maximum displacement of during construction is 1.7 times larger than the displacement of final construction. 3. The bridge behavior considering the construction step is somewhat different from that of final stage in whole structure and the displacement and stress during construction is larger than that of final construction. Therefore, it needs the reasonable structural design considering the construction step to get economical efficiency and a high competitive construction.