• Polymer(Korea)
• /
• v.35 no.1
• /
• pp.94-98
• /
• 2011

Poly(2-hydroxyethyl methacrylate), PHEMA, hybrid gels containing Pluronic and acrylic acid (AAc) were prepared as new biocompatible and stimuli-responsive hydrogels by photo-polymerization technique. The prepared hybrid gel showed reversible, temperature-responsive swelling behavior due to the presence of Pluronic component, which underwent sol-gel transition at an elevated temperature to cause gel shrinkage. The hydrogel also exhibited increased swelling degrees and pH-sensitivity due to the AAc component with ionizable carboxylic acid groups. The microporous gel morphology and its changes upon stimuli was observed by scanning electron microscopy.

• Proceedings of the Korea Concrete Institute Conference
• /
• 1993.04a
• /
• pp.59-64
• /
• 1993

The flexural and horizontal shear behavior of overlaid concrete slabs is investigated in the present study. An experimental program was set up and several series of overlaid concrete slabs have been tested to study the effect of different surface preparation ; and dowels between old slab and overlay under service load. The present study indicates that the overlaid concrete slabs behave integrally with existing bottom slabs up to yield range for rough and doweled joints.

• Proceedings of the Korea Concrete Institute Conference
• /
• 1993.10a
• /
• pp.213-219
• /
• 1993

The box girder was developed using polymer concrete, box girder were made for flexural behavior evaluation. The box girder was reinforced with reinforcing steel bars and fiber glass roving cloths. Failure loads were 13.5 tons and 16.6tons for steel reinforced girder and fiber glass reinforced girder, respectively. Especially for the fiber glass reinforced girder, the shape was not changed even after failure. It is expected that application of this idea will be useful for developing under ground box, girder, utility tunnel, small stream bridge box, etc.

• Proceedings of the Korea Concrete Institute Conference
• /
• 1993.10a
• /
• pp.261-266
• /
• 1993

This study was performed to evaluate the flexural behavior of polymer concrete sandwich panels which was made of unsaturated polymer resin. Bending tests under 4point loading was conducted for the 8 type of sandwich panel with different core and facing thickness. Results show that Load-Deflection, shearing force- shear strain, moment strength - strain relationships were effected by core and facing thickness.

• 한국가스학회:학술대회논문집
• /
• 2005.05a
• /
• pp.218-218
• /
• 2005

• Proceedings of the Korea Concrete Institute Conference
• /
• 1992.04a
• /
• pp.67-73
• /
• 1992

Polymer-Impregnated Concrete(PIC) is a new polymer-concrete composite material which consist of basic cement concrete and polymer. The mechanical properties and behavior of PIC depend on the type of polymers and the impregnation techniques. In general, the polymer impregnation can improve the strength, durability and ductility of normal concrete. The objective of this study is to develop the analytical procedure for analyzing the structural responces of polymer-impregnated concrete beams with different polymer loading by using finite element method on the basis of experimental results.

• Magazine of the Korean Society of Agricultural Engineers
• /
• v.28 no.2
• /
• pp.74-86
• /
• 1986

유동화콘크리트의 공학적 특성에서 시간-의존거동을 확인하기 위하여,나프타렌 설폰산염 폴리머 고축합물인 Rheobuild 1000과 메라민 설폰산염 고축합물인 NP-20의 고성능감수제를 사용한 유동화콘크리트와 보통콘크리트를 제조하여 비교.고찰을 행하였으며, 고성능감수제의 종류 및 함량이 콘크리트의 공학적 특성에 미치는 영향을 구명하기 위하여 재령 3일, 14일, 28일, 60일, 90일, 180일의 압축강도를 측정, 조기 및 장기압축강도를 조사하였고, 인장강도 및 탄성 변형에 미치는 영향을 조사하였다. 또한 습윤 및 에어콘디션의 양생조건하에서 시간의 경과에 따른 건조수축 및 크리이프 변형을 조사.분석함으로써 유동화콘크리트의 시간-의존거동을 확인하였다. 실험결과, 사용 고성능 감수제의 종류에 따라 차이는 있으나, 고성능 감수제의 사용은 일반적으로 워커빌리티 성능을 개선하고 압축 및 인장도를 크게 향상시키며, 탄성계수는 보통의 콘크리트에 비하여 높게 나타났다. 또한 건조수축 및 크리프 변형의 감소에 매우 양호한 결과를 나타내어 앞으로 건설용 용도로써 효과적인 것으로 판단되었다.

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 2010.04a
• /
• pp.445-448
• /
• 2010

본 연구는 섬유 보강 폴리머(Fiber Reinforced Polymers, 이하 FRP) bar로 보강된 콘크리트 깊은 보의 전단강도를 평가하기 위하여 전단경간비, 보강비, 주근의 종류를 변수로 총 6개의 실험체에 대한 전단 실험을 수행하였다. 전단실험을 토대로 FRP bar로 보강된 콘크리트 깊은보의 균열 및 처짐에 대한 거동 조사를 수행하였으며, ACI 318-08의 스트럿-타이 모델을 이용한 전단강도와 아치작용을 고려한 기존 제안식에 의한 전단강도를 비교 평가하였다. 그 결과, FRP bar로 보강한 실험체와 철근으로 보강한 실험체는 상이한 전단거동을 보였으며, FRP bar로 보강한 경우의 전단강도가 철근으로 보강한 경우보다 증가하는 것으로 나타났다. 전단강도 산정에 있어서는 ACI 318-08의 스트럿-타이 모델을 이용한 방법이 기존 제안식에 의한 방법보다 상대적으로 정확했다.

• Magazine of the Korea Concrete Institute
• /
• v.7 no.6
• /
• pp.233-241
• /
• 1995

In this thesis, the fatigue tests were performed on a series of R /C beams repaired with co& crete-lmlyrner composites to investigate the fatigue bahavior. The three point loading system is used in the fatigue tests. In these tests, relations between the repeated loading cycles and mid-span deflections, number of repeated loading cycles when repaired beams were fractured, the bonding performance of repair materials were observed. On this basis, the mid-span deflections, the crack growth and failure mode of repaired R /C beams were studied. A S-N curve was drawn to present the fatigue strength of repaired beams. From the test results, it was shown that behavior of R /C beams repaired with polymer-cement series were very sirnillar to control beam about bonding performance, mid-span deflections and fatigue strength according to S-N curve drawn by the regression anlysis on the fatigue test results.

• Journal of the Society of Disaster Information
• /
• v.16 no.3
• /
• pp.602-610
• /
• 2020

Purpose: This paper aims to develop an asphalt pavement system with reduced cracks, structural stability and waterproofing at sub-zero temperature conditions. Method: Under various temperature conditions, SIS polymer asphalt, normal asphalt, and guss asphalt were tested for adhesion strength of the binder and deformation strength of the mixture. Result: The adhesion strength of asphalt binder was higher in SIS polymer asphalt than that of normal asphalt and guss asphalt. The deformation strength of the asphalt mixture was almost the same as that of SIS polymer asphalt and normal asphalt. The energy absorption of the SIS polymer asphalt mixture was relatively higher than that of the normal asphalt mixture and the guss asphalt mixture. Conclusion: The maximum load of the SIS polymer asphalt mixture was lower than that of the guss asphalt mixture. However, in sub-zero temperature conditions, sufficient energy absorption was secured by stable load reduction. Therefore, it is expected to improve the durability of asphalt pavement by reducing the occurrence of microcracks with stable fracture behavior.