Journal of the Korean Recycled Construction Resources Institute (한국건설순환자원학회논문집)

Korean Recycled Construction Resources Institute (한국건설순환자원학회)
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Double Punch Tensile Strength of Cylindrical Mortar with Steel Fibers aligned in Circumferential Direction by Electro-Magnetic Field

전자기장을 이용하여 강섬유를 원주방향으로 배열시킨 원통형 몰탈의 Double Punch 인장강도

  • Received : 2022.01.11
  • Accepted : 2022.02.15
  • Published : 2022.03.30
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Abstract

In this study, the direction of the steel fibers mixed in the normal mortar and the steel slag mortar was arranged in the circumferential direction by using an electromagnetic field, and a double punch test was performed to evaluate the effect of magnetic filed exposure on tensile strength and on fracture energy. As a result of the experiment, it was confirmed that it is possible to arrange the steel fibers in the circumferential direction. Tensile strength and displacement at failure were also increased according to the arrangement of steel fibers due to exposure to electromagnetic fields. On the other hand, the fracture energy hardly increased. It is considered that there was a limit in resisting crack growth because the area where the arrangement of steel fibers could be adjusted under the electromagnetic field was not deep to center of specimen and the end shape of the steel fibers were straight not hooked. Additional research is needed to address these issues.

본 연구에서는 전자기장을 이용하여 일반몰탈과 스틸슬래그 몰탈 내부에 혼입되는 강섬유의 방향을 원주방향으로 배열시켰으며, 성능변화를 확인하기 위하여 Double Punch 실험을 수행하였다. 실험결과, 전자기장을 이용하여 강섬유를 원주방향으로 배열하는 것이 가능한 것으로 확인되었다. 전자기장 노출로 인한 강섬유의 배열조정에 따라 인장강도와 파괴 시 변형도 유의미한 증가를 보였다. 반면 파괴에너지는 거의 증가하지 않았다. 전자기장이 영향을 미쳐 강섬유의 배열이 조정되는 구간이 크지 않은 문제와 사용한 강섬유가 직선으로 되어 있어 균열성장을 억제하는데 한계가 있었던 것으로 판단된다. 이와 같은 문제를 보완한 추가연구가 필요하다.

Keywords

Acknowledgement

이 논문은 한국연구재단 이공분야기초연구사업 중 기본연구지원사업(과제번호 : 2020R1F1A1076566)의 연구비 지원으로 수행, 작성되었으며, 이에 감사합니다.

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