Journal of the Architectural Institute of Korea Structure & Construction (대한건축학회논문집:구조계)

Architectural Institute of Korea (대한건축학회)
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Shrinkage Crack Control of Hwangtoh Mortar using Fiber and Admixture

섬유 및 혼화제를 이용한 황토 모르타르의 수축균열 제어

  • 문주현 (경기대 일반대학원 건축공학과) ;
  • 양근혁 (경기대 플랜트.건축공학과) ;
  • 전중규 (코오롱글로벌 R&BD센터 기반시설연구소) ;
  • 황혜주 (목포대 건축학과)
  • Received : 2012.03.14
  • Published : 2012.08.25
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Abstract

A total of 8 hwang-toh mortar mixes with no cement were tested to evaluate the effect of different fibers and admixtures on the control of shrinkage cracks of such mortars. The fiber types added were Lyocell, Poly-Amid and PVA, while, CSA and organic polymer were selected as the admixture. The shrinkage crack resistance of hwang-toh mortar were examined from the unrestrained drying shrinkage strain, restrained drying shrinkage and plastic shrinkage. Test results revealed that the unrestrained drying shrinkage strain of hwang-toh mortar sharply increased at an early age showing approximately 2.5 times higher values than predictions obtained from ACI 209, regardless of the addition of fibers and admixtures. In addition, cracks owing to the restrained drying shrinkage developed at the only age of 1.6 days in all test mixes; as a result, the cracking grade of hwang-toh mortar was evaluated to be high. On the other hand, the addition of fibers required a value of fiber spacing above 0.0003 in order to enhance the tensile resistance capacity of hwang-toh mortar under the restrained drying shrinkage and reduce the cracking area under the plastic shrinkage. Overall, it could be concluded that moist curing at an early age and the addition of fiber with fiber spacing above 0.0003 are practically effective in reducing shrinkage crack of hwang-toh mortar.

Keywords

Acknowledgement

Supported by : 국립문화재연구소

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