• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1997년도 봄 학술발표회 논문집
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• pp.383-391
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• 1997

The prediction of effective properties of heterogeneous material like concrete is of primary importance in design or analysis. This paper os about micromechanice-based evaluation of elastic moduli of concretes considering composite material behavior. In this study, micromechanixe-based schemes for the effective elastic modui of the lightweight foamed concrete and the normal concrete are proposed based on averaging techniques using a single-layered inclusion model and a multi-phase and multi-layered inclusion model. respectively, For the verification's sake, elastic moduli evaluated in this study are compared with experimental data and results by existing formula.

• 한국도로학회논문집
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• 제10권4호
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• pp.91-101
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• 2008

본 연구에서는 기본설계용 다층탄성이론을 이용한 역학적 거동해석 프로그램을 개발하였고, 현장에서 간편하게 사용될 수 있도록 Visual Basic 프로그래밍을 사용한 사용자 편의의 전 후 처리기법을 도입하여 본 연구에서 개발된 다층탄성해석 프로그램을 패키지화하였다. 패키지화한 상용프로그램에 아스팔트층의 깊이별 온도변화에 따른 영향과 보조기층, 노상과 같은 비구속층에서의 응력비선형성을 고려하여 아스팔트 포장구조해석모형을 개발하였다. 또한 개발된 해석과정을 이용하여 시험도로 실제 초기 현장계측자료의 현장검증을 실시하였다.

• 한국도로학회논문집
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• 제16권2호
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• pp.53-59
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• 2014

PURPOSES : This study estimated an asphalt pavement internal behavior under uphill lanes considering reducing speed of heavy truck on uphill slope. METHODS : Truck performance curve which has been adapted to "Korea Highway Capacity Manual" was analyzed. And asphalt pavement internal behaviors were estimated with Multi-layered elastic analysis using KPRP(Korea Pavement Research Program) dynamic modulus prediction equations. RESULTS : As a result, it is shown that when the standard truck drives 2.0 km at a speed of 80 km/h in 8% climbing slope, it's speed reduced to 25.4 km/h, at same time frequency in asphalt layer decrease to 67.2% and it's dynamic modulus degrades to 30.9%. Based on these results, internal behavior as decreasing vehicle speed on uphill lanes were estimated. CONCLUSIONS : From the results of Multi-layered elastic analysis, internal behavior showed that when the standard truck drives 2.0 km at a speed of 80 km/h in 8% slope on uphill lanes, vertical strain was increased to 44.4% at the bottom of surface course, and lateral tensile strain was increased to 20.5% at the bottom of base course.

• 한국군사과학기술학회지
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• 제21권1호
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• pp.25-39
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• 2018

In this paper, an integrated analysis model for evaluating the underwater acoustic performance of the multilayered acoustic coatings containing visco-elastic composite layers with hollow glass microspheres is described. The model uses the effective medium theory considering the acoustic scattering and resonance effects of the inclusions. Also, the model incorporates the compressive deformation mechanism associated with hydrostatic pressure. The technique developed in this work was used as the acoustic layer design and performance analysis tools for the practical hull coatings and acoustic baffles in Korean next generation submarines.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2008년도 춘계학술발표대회 및 제14회 신소재 심포지엄
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• pp.14.1-14.1
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• 2008

• 한국도로학회:학술대회논문집
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• 한국도로학회 2004년도 춘계학술대회 논문집
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• pp.29-34
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• 2004

• 한국도로학회:학술대회논문집
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• 한국도로학회 2003년도 학술발표회 논문집
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• pp.69-75
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• 2003

• Structural Engineering and Mechanics
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• 제73권6호
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• pp.667-684
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• 2020

In this article, the static responses of layered magneto-electro-thermo-elastic (METE) plates in thermal environment have been investigated through FE methods. By using Reddy's third order shear deformation theory (TSDT) in association with the Hamilton's principle, the direct and derived quantities of the coupled system have been obtained. The coupled governing equations of METE plates have been derived through condensation technique. Three layered METE plates composed of piezoelectric and piezomagnetic phases are considered for evaluation. For investigating the correctness and accuracy, the results in this article are validated with previous researches. In addition, a special attention has been paid to evaluate the influence of different electro-magnetic boundary conditions and pyrocoupling on the coupled response of METE plates. Finally, the influence of stacking sequences, magnitude of temperature load and aspect ratio on the coupled static response of METE plates are investigated in detail.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
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• pp.671-674
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• 2004

This paper presents design and analysis of multi-layered ring-dot type piezoelectric transformer. These transformers are useful for step up and step down. The transformers consist of disk type multi-layered piezoelectric ceramic plates. The finite element method(FEM) was used for analysis transformer. Vibration mode, electric field and equivalent elastic strain of piezoelectric transformer were simulated by changing frequency. As results, the strain was distributed in isolation part entirely. We can get the operated in step up transformer when the inner side electrode using by input parts. Also we can get the step down transformers using by input Part as outer side electrode. The step up ratio and step down ratio was increased by decreasing inner side electrode. The resonance frequency was increased by increasing inner side electrode when the transformer was operated in step down transformer. But the step up one was decreased. From these results, we can expect to multi-layered ring-dot type piezo transformers as step up and step down transformers.

• 한국지반공학회지:지반
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• 제6권4호
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• pp.19-32
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• 1990

일반적으로 지반은 복잡하고 다양한 다층구조로 되어있다. 이러한 다층토 지반을 해석 하기 위 해 본문은 지반의 구성식,층의 구조와 두께, 각층의 강성, 재하조건 등을 변화시켜 수치해석 하였다. 기존의 다층토 지반은 Burmister의 2층계이론인 탄성해로 지중응력분포를 해석하였으나,여기서는 Biot방정식을 지배방정식으로하여 개발된 지반해석프로그램에 탄 .점소성구성식을 이용하여 층의 조건에 관계없이 2층이상의 모든 다층토지반의 지중응력분포를 해석 하고자 한다. 이들의 결과를 Burmister나 Fok의 결과와 비교하였으며, 서로 근접한 결과를 얻었다. 따라서, 본 연구는 다양한 다층토 지반을 전산 프로그램을 이용하여 실제에 가까운 응력전달기구 를 밝히려는 목적으로 수행된 것이다.