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2014 Vol.16, Issue 2 Preview Page
Long-term strength of shotcrete with improved C12A7 based mineral accelerator

개량형 C12A7계 광물계 급결제를 사용한 숏크리트의 장기강도 평가

Jong-Pil Won1*
,
Un-Jong Hwang2
,
Su-Jin Lee3
,
Jae-Ho Lee2
,
Seok-Bu Jang4
원 종필1*
,
황 언종2
,
이 수진3
,
이 재호2
,
장 석부4
1Professor, Dept. of Civil Environmental System Engineering, Konkuk Univ.
2Graduate Student, Dept. of Civil Environmental System Engineering, Konkuk Univ.
3Post Doc. Researcher, Dept. of Civil Environmental System Engineering, Konkuk Univ.
4General Manager, Samsung C&T Corporation Eng. & Con. Group
1건국대학교 사회환경시스템공학과 교수
2건국대학교 사회환경시스템공학과 석사과정
3건국대학교 사회환경시스템공학과 박사 후 연구원
4삼성물산 건설부문 지하토목팀 부장
*교신저자. *Corresponding Author. 
31 March 2014. pp. 135-148
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Abstract

This study was performed to evaluate the performance about Improved C12A7 based mineral accelerator (ICM) increased in initial and long-term strength. ICM was developed to overcome the long-term strength decrease in existing accelerator. To evaluate the performance of ICM according to addition rate, setting time, compressive strength, and flexural strength tests were conducted in laboratory. In results, initial setting time was slower, final setting time was faster than existing C12A7 based mineral accelerator (CM) when usage of ICM 6%. In compressive and flexural strength, existing CM was higher than ICM at 3hours and 1day. After 7days, strength of shotcrete using ICM was increased. Rebound test, compressive strength and flexural strength test with optimum addition rate through the laboratory test were conducted in field. Field experiment results were the same as laboratory test. Long-term strength performance of ICM was superior to existing accelerator.

Keywords
Admixture
C12A7 mineral based accelerator
Long-term Strength
Shotcrete

본 연구에서는 숏크리트의 품질을 안정적으로 만들기 위해 초기 및 장기강도성능을 향상시킨 개량형 C12A7계 광물계 급결제의 성능 평가를 실시하였다. 개량형 C12A7계 광물계 급결제는 기존 급결제들이 가지고 있는 장기강도 저하를 극복하고자 개발되었다. 개량형 C12A7계 광물계 급결제의 혼입량에 따른 성능을 평가하기 위해 실내에서 응결시간, 압축강도 및 휨강도를 실시하였다. 실험결과 응결시간은 개량형 C12A7계 광물계 급결제를 6%이상 사용하였을 때 기존 C12A7계 광물계 급결제에 비해 초결은 느리지만 종결은 빠르게 나타났다. 압축강도 및 휨강도는 기존의 C12A7계 광물계 급결제가 초기재령 3시간, 1일에서는 높게 나타났지만 7일 이후로 갈수록 개량형 C12A7계 광물계 급결제를 사용한 숏크리트의 강도가 증가하였다. 또한 실내실험에서 도출된 최적혼입률을 적용하여 현장 적용성을 평가하였다. 현장실험으로는 리바운드, 압축강도 및 휨강도를 실시하였다. 현장실험 결과` 실내실험과 같이 개량형 C12A7계 광물계 급결제를 사용한 숏크리트의 장기강도성능이 우수하게 나타났다.

키워드
개랑형 C12A7계 광물계 급결제
숏크리트
장기강도
혼화재
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Information
  • Publisher :Korean Tunneling and Underground Space Association
  • Publisher(Ko) :한국터널지하공간학회
  • Journal Title :Journal of Korean Tunnelling and Underground Space Association
  • Journal Title(Ko) :한국터널지하공간학회 논문집
  • Volume : 16
  • No :2
  • Pages :135-148
  • Received Date : 2014-02-05
  • Revised Date : 2014-02-20
  • Accepted Date : 2014-02-28
  • DOI :https://doi.org/10.9711/KTAJ.2014.16.2.135
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