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Dispersibility and Flexural Toughness Evaluation of Fiber Reinforcement Cellular Sprayed Concrete by added Foam

기포를 혼입한 섬유보강 셀룰러 스프레이 콘크리트 공법의 분산성 및 휨인성 평가

  • Received : 2015.05.19
  • Accepted : 2015.06.11
  • Published : 2015.06.30

Abstract

In this paper, dispersibility of steel fiber is improved mixing with form for material development of protection and blast resistant structure sprayed concrete. And it is developed a high toughness cellular sprayed concrete material using steel fiber. Oversupply form for dispersibility improvement of steel fiber is mostly fade away through sprayed, finally it is satisfied with the proper mixing ratio under 3 % ~ 6 %. This is considered for compressive strength and flexural toughness. Test results of compressive strength showed superior strength capability in 28, 56 days, also flexural strength and flexural toughness is great. Then oversupply form is enhanced for dispersibility of steel fiber and I think that it did not cause decreasing of strength. But analysis results of pore structure through image analysis failed for a great spacing factor and specific surface area. This is largely measured in spacing factor because air content have a grate evaporation effect for sprayed.

Keywords

cellular;dispersibility;flexural toughness;sprayed concrete;steel fiber

References

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Acknowledgement

Supported by : 국토교통부