• Composites Research
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• 제13권1호
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• pp.25-32
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• 2000

국부압축력을 받는 스트링거 보강 복합적층 만곡 판넬의 좌굴 및 후좌굴 거동을 개발한 유한요소프로그램을 이용하여 해석하였다. 후좌굴 해석은 판넬거동을 세 가지로 나누어 해석하였다. 판넬과 보강재를 모델링 하기 위하여 8절점응축 쉘요소를 도입하고 비선형유한 요소 수식화를 위해 2nd Piola-Kirchhoff 응력텐서와 Lagrangian 변형률 텐서를 채택하였다. 파손 특성을 고려하기 위해 점진적 파손해석을 도입하였다. 국부축하중을 받는 복합적층 만곡 판넬의 좌굴하중 및 좌굴후 극한하중, 국부좌굴과 전체좌굴, 그리고 보강재 영향이 인자별로 해석 비교 된다.

• Steel and Composite Structures
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• 제9권5호
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• pp.397-418
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• 2009

Eight panel specimens were tested in one-way bending to study the behaviour and capacity of composite slab joists consisting of cold-formed steel C-sections and concrete. Various shear transfer mechanisms were implemented on the C-section flange embedded in the concrete to provide the longitudinal shear resistance. Results showed that all specimens reached serviceability limit state while in elastic range and failure was ductile. Shear transfer achieved for all specimens ranged from 42 to 99% of a full transfer while specimens employed with shear transfer enhancements showed a greater percentage and therefore a higher strength compared with those relying only on surface bond to resist shear. The implementation of pre-drilled holes on the embedded flange of the steel C-section was shown to be most effective. The correlation study between the push-out and panel specimens indicated that the calculated moment capacity based on shear transfer resistance obtained from push-out tests was, on average, 10% lower than the experimental ultimate capacity of the panel specimen.

• Steel and Composite Structures
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• 제26권3호
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• pp.255-263
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• 2018

A steel-concrete composite (SC) panel typically consists of two steel faceplates and a plain concrete core. This paper investigated the impact response of SC panels through drop hammer tests and numerical simulations. The influence of the drop height, faceplate thickness, and axial compressive preload was studied. Experimental results showed that the deformation of SC panels under impact consists of local indentation and overall bending. The resistance of the panel significantly decreased after the local failure occurred. A three-dimensional finite element model was established to simulate the response of SC panels under low-velocity impact, in which the axial preload could be considered reasonably. The predicted displacements and impact force were in good agreement with the experimental results. Based on the validated model, a parametric study was conducted to further discuss the effect of the axial compressive preload.

• Journal of the Korean Wood Science and Technology
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• 제23권4호
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• pp.74-84
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• 1995

Eight types of thin composite panels were manufactured by press-lam and mat-forming process applied to optimum manufacturing condition, studied in former first research by author (1995). They were tested and compared with control boards on dimensional stability, internal bond strength, tensile strength, Screw withdrawal strength, and bending properties. These thin composite panels manufactured by mat-forming process were generally superior to those by press-lam in dimensional stability and mechanical properties. In the dimensional stability and mechanical properties of thin composite panels manufactured by mat-forming process, the thin composite panels (A and E type) composed of particle or sawdust core and veneer face with polyethylene film, were as good as those of common plywood (control board). Internal bond strength showed highest value in the thin composite panel(D type) which composed of particle core and polypropylene screen face with polyethylene film. The thin composite panels(G and H type) composed of sawdust or particle core and polypropylene screen face with polyethylene film by press-lam and mat-forming process, showed most highest value in dimensional stability and water absorption.

• Steel and Composite Structures
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• 제24권6호
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• pp.727-740
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• 2017

The present paper studies the stability analysis of the continuously graded CNT-Reinforced Composite (CNTRC) panel stiffened by rings and stringers. The Stiffened Panel (SP) subjected to axial and lateral loads is reinforced by agglomerated CNTs smoothly graded through the thickness. A two-parameter Eshelby-Mori-Tanaka (EMT) model is adopted to derive the effective material moduli of the CNTRC. The stability equations of the CNRTC SP are obtained by means of the adjacent equilibrium criterion. Notwithstanding most available literature in which the stiffener effects were smeared out over the respective stiffener spacing, in the present work, the stiffeners are modeled as Euler-Bernoulli beams. The Generalized Differential Quadrature Method (GDQM) is employed to discretize the stability equations. A numerical study is performed to investigate the influences of different types of parameters involved on the critical buckling of the SP reinforced by agglomerated CNTs. The results achieved reveal that continuously distributing of CNTs adjacent to the inner and outer panel's surface results in improving the stiffness of the SP and, as a consequence, inclining the critical buckling load. Furthermore, it has been concluded that the decline rate of buckling load intensity factor owing to the increase of the panel angle is significantly more sensible for the smaller values of panel angle.

• 대한기계학회논문집A
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• 제34권1호
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• pp.55-60
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• 2010

틸팅형 고속열차의 차체에 적용되는 하니컴 복합재 조인트 구조물의 경우 운행중 외팔보형 굽힘하중을 받게된다. 하이브리드 복합재 조인트 구조물에 대한 굽힘시험평가를 수행하기 위해 실제 틸팅열차 차체 구조물에서 조인트부를 절단 채취하여 시험편으로 제작하였다. 굽힘시험결과 시험편의 파괴거동은 정적하중과 피로하중하에서 확연히 달라짐을 보였다. 정적굽힘하중 하에서는 하니컴 코어 영역에서 전단변형과 파괴가 발생하였으며, 피로굽힘하중 하에서는 복합재 표피층과 하니컴 코어층 사이에서 계면분리가 발생하거나, 또는 금속재 언더프레임과의 용접부에서 파괴가 발생하였다. 이러한 파괴거동은 다른 산업분야에서 사용되는 유사한 구조의 하니컴 복합재 조인트 구조물에서도 발생할 수 있기 때문에, 본 실험 결과를 하니컴 복합재 조인트 구조물의 설계변수를 개선하기 위해 이용될 수 있다.

• 한국화재소방학회논문지
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• 제26권6호
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• pp.92-98
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• 2012

본 연구에서는 건축 외장재로 많이 사용되고 있는 알루미늄복합패널의 일반재와 난연재에 대한 실제 화재에서의 화재성상을 분석하기 위하여 실대형 시험(ISO 13785-2)을 수행하였다. 시험결과, 일반재인 경우 최고 온도가 210초에 $1,021^{\circ}C$가 측정되었으며, 난연재는 약 1,200초에 $1,190^{\circ}C$가 측정되었다. 화재성상은 알루미늄복합패널 중 난연재의 경우 착화가 더디게 진행되었으며, 일반재의 알루미늄복합패널은 연소착화와 동시에 화재가 빠르게 확산되었다. 일반재와 난연재의 알루미늄복합패널은 연소착화하는데는 분명한 차이를 보였지만, 일단 착화된 이후에는 수직화염의 확산의 연소형태는 일반재나 난연재 모두 빠르게 수직확산되는 비슷한 양상을 보였다. 이에 본 연구결과, 알루미늄복합패널에 대한 화재위험성을 줄이기 위해서는 난연재 사용을 적극적으로 유도하도록 하며, 또한, 일단 착화 후에는 이를 진압할 외장재 전용 소화설비의 적용이 시급함을 알 수 있었다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1997년도 가을 학술발표회 논문집
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• pp.761-768
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• 1997

Recently, on account of the lack of skilled labor and the increase of labor costs, it has been more difficult the construction environment. Now new methods were developed and used many places. This study is concerning the structural performance of Composite Form Panel Method-one of the new methods-of the wall type. It is available to make monolithic system of bearing wall and half slab. This paper presented design and product data by experiments.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2017년도 공동학술발표회
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• pp.251-251
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• 2017

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2001년도 춘계학술발표대회 논문집
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• pp.97-101
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• 2001

Composite materials have been applied widely in interior panels of buildings and transport vehicles. Recently good fire performance and weight reduction are key issues in the fields. In the present study we investigated effects of processing parameters on the performance of honeycomb sandwich panels, especially peel strength of the panel and fire performance. The processing parameters considered were types of matrix resin, resin contents, panel cure conditions, and surface painting process conditions. The results showed that the higher resin content provides the better peel strength. Controled cure steps are also needed to obtain good pee] strength. Paint processing parameters including base putty thickness and paint drying conditions and paint thickness are important to obtain good paint adhesion and good fire performance.