• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2016년도 추계 학술논문 발표대회
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• pp.24-25
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• 2016

In this study, the thermal strain of high strength concrete with the compressive strength of 80, 130, 180MPa were measured under 25% of compressive strength loading condition. As results, it is considered that decline of the elastic modulus and shrinkage strain of high strength concrete become grater at the elevated temperatures.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2012년도 춘계 학술논문 발표대회
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• pp.63-64
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• 2012

In case of concrete, it should be deformed by many factors, such as explosive spalling, thermal strain and creep at high temperature. Structural fire design has been proposed to predict fire damage as national standard. It is general safer to use values obtained from tests of unstressed residual test in stead of stressed test. But most of thermal properties on concrete were conducted with normal aggregate. In this study, it evaluated mechanical properties of concrete with aggregate type and loading condition. we use normal and light aggregate to have different thermal properties. Also, we test mechanical properties to use Ø100×200 mm cylinder specimen according to target temperature and 0%, 20%, 40% loading.

• Computers and Concrete
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• 제1권2호
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• pp.189-209
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• 2004

Several extensions to the Thelandersson phenomenological model for concrete under transient high temperatures are explored. These include novel expressions for the temperature degradation of the elastic modulus and the temperature dependency of the coefficient of the free thermal strain. Furthermore, a coefficient of thermo mechanical strain is proposed as a bi-linear function of temperature. Good qualitative agreement with various test results taken from the literature is demonstrated. Further extensions include the effects of plastic straining and temperature dependent Poisson's ratio. The models performance is illustrated on several simple benchmark problems under uniaxial and biaxial stress states.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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• pp.220-221
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• 2017

In this study, the thermal strain of high strength concrete with the compressive strength of 70, 80, 100MPa were measured under 33% of compressive strength loading condition. As results, it is considered that shrinkage strain of high strength concrete become grater at the elevated temperatures.

• 한국철도학회논문집
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• 제9권6호
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• pp.644-651
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• 2006

An application of concrete track is being actively processed for the construction of Korean railroad. The concrete track has an advantage to decrease the maintenance ire, but is very difficult system to maintain after earthwork settlement occurred. Therefore, the management and control of embankment and foundation settlement is very important for the successful concrete track construction. We expect that the main part of the settlement of the concrete track is the one of embankment and foundation supporting it. Settlements vulnerable to the concrete track among the causes of lots of settlements are primary consolidation and secondary compression settlement of foundation, creep settlement of embankment, settlement caused by train load, and unequal settlement resulting from the difference of embankment material and construction process. This paper investigated the settlement causes to make badly effects on the concrete track and also evaluated the settlement with field tests and numerical analysis.

• Computers and Concrete
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• 제9권5호
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• pp.357-374
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• 2012

The aim of this paper is to develop a procedure able to calculate the long-term stress and strain patterns in modern prestressed composite structures which are largely influenced by creep and shrinkage and whose final static configuration is the result of many phases of loading and restraints conditions. The introduction of equivalent moduli, depending on the viscous and elastic features of materials, can guarantee a significant simplification of the problem presented above. The proposed calculation model has been used to design the "Quattroquercie Viaduct" located on the highway "A3" Salerno-Reggio Calabria, Italy.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1999년도 봄 학술발표회 논문집
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• pp.210-217
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• 1999

This paper deals with the analysis for column shortening of RC frame structure considering the construction sequences. The time-dependent effects of concrete are taken into consideration in this study to simulate the actual structural behavior. The stiffness matrix of a beam element is derived on the bases of the layer approach, dividing a section with imaginary layers. Creep and shrinkage strains at each layer are calculated by using the first-order algorithm based on the expansion of creep compliance. Finally, the correlation studies with the purpose of analyzing the time-dependent behavior of building structure are conducted using the analytical model proposed in this study.

• 콘크리트학회논문집
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• 제22권4호
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• pp.567-574
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• 2010

지금까지 환경 친화적 재료로서 황토에 관한 연구는 포틀랜드 시멘트를 부분적 대체하거나, 완전 대체하는 연구로 진행되어 왔다. 기존의 대부분의 연구에서는 압축강도, 건조수축, 크리프 등 황토 콘크리트의 역학적 성질에 초점이 맞춰졌다. 이 연구에서는 황토 콘크리트로 제작된 보 실험체의 휨 성능을 실험하였다. 이번 실험에서는 시멘트를 20% 대체하는 활성 황토를 사용한 콘크리트와 시멘트를 100% 대체하는 활성 황토 콘크리트가 사용되었다. 단순보 실험은 2점 정적 재하 하중으로 실험하였다. 휨 강도, 균열 모멘트, 처짐, 연성도 등의 결과를 일반 포틀랜드 시멘트 콘크리트로 제작된 보의 실험 결과와 비교하였다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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• pp.337-340
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• 2004

In recent days, the beneficial effects of using fiber reinforced concrete, especially Steel Fiber Reinforced Concrete, have been on the rise. However, few studies on long-term behavior of SFRC are executed in spite of great demand of SFRC. The fact that SFRC is far better than NRC in various properties such as tensile strength, ductility, flexural toughness has been certified by many researchers. And, those advantages can be also applied to decrease the structures deterioration induced by creep and shrinkage. Furthermore, even though it is fact that SFRC is generally used in joint members to distribute concentrated stresses by fibers, SFRC is treated as NRC in designing especially for long-term behavior of structures. So this paper is about a study on the long-term response of SFRC applied to HPC about 40MPa. Therefore, in this paper, the test results of eighteen high-strength concrete specimens and steel fiber-reinforced concrete specimens, with steel fiber content of $1\%$ by volume were presented. The test result shows that SFRC is advantageous rather than NRC in long-term response.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2007년도 정기 학술대회 논문집
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• pp.557-562
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• 2007

In order to analyze the PSC box-girder bridge by the cantilever construction method, three dimensional analysis method using the PSC shell clement is suggested. The time dependent material functions are based on the ACI and CEB code. The time dependent concrete material properties considered are changes in strength, elastic modulus, creep and shrinkage. For the prestressing tendon, relaxation effects are considered. Anchorage and friction loses during tendon installations are also included. The ACI and CEB material models for creep and elastic modulus are also included.