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Performance of Steel Fiber Reinforced Shotcrete using Alkali Free Based Accelerator

알칼리 프리계 급결제를 사용한 강섬유 보강 숏크리트의 성능 평가

  • 백철우 (유진종합개발(주) 기술연구소) ;
  • 박찬기 (건국대학교 사회환경시스템공학과) ;
  • 전언중 (건국대학교 대학원 지역건설환경공학과) ;
  • 원종필 (건국대학교 사회환경시스템공학과)
  • Published : 2004.05.30

Abstract

Modern underground and tunnel works that the wet type shotcrete is getting widely designed and applied in a large scale project. Further to its applications, the needs of improving the performance of the shotcrete, such as new and developed additives and accelerators fur increasing the performance of shotcrete, become the most important issue in the field. The main objective of this study evaluated to performance of steel fiber reinforced shotcrete using alkali free based accelerator for the durability and high quality of shotcrete. The major test variables are accelerator type and its dosage. One type silicate based accelerator and one type aluminate based accelerator and one type alkali free based accelerator were used. The dosage of accelerators is determined by the manufactures and laboratory test condition. Compressive strength test results showed that the dosage of silicate and aluminate based accelerators caused reduction of mechanical properties of shotcrete. Compressive strength of alkali free based accelerator is more stable than of silicate and aluminate based accelerators. Also, according to the compressive strength and flexural test results, it was found that steel fiber reinforced shotcrete used alkali free based accelerator could attain significant improvement in the mechanical and flexural performance.

Keywords

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