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Mechanical Properties of Repair Mortar Incorporated with Bio Polymer

바이오 폴리머를 이용한 구조물 보수용 모르타르의 역학적 특성 평가

  • 이선목 ((주)정우소재 기술연구소) ;
  • 현정환 (충남대학교 건설방재연구소) ;
  • 권기성 (충남대학교 토목공학과) ;
  • 김윤용 (충남대학교 토목공학과)
  • Received : 2018.08.16
  • Accepted : 2018.10.29
  • Published : 2018.11.01

Abstract

In recent years, more than 5,000 tons of sargassum honeri have been infested in the southern coast and the coast of Jeju Island, causing serious damage to the farms and fisheries, and environmental problems. The alginate contained in the sargassum honeri is a natural polymeric substance mainly used for medicines and foods. However, since there is no way to utilize it in large quantities, a study was carried out to utilize bio polymer obtained from sargassum honeri in producing polymer mortar for repairing deteriorated infrastructures. From the tests of setting time, it was found that the L0BP12 mixture containing 12% of bio polymer increased the setting time by 20% as compared with the L12BP0 mixture using only synthetic polymer. From the tests of water absorbtion, the LOBP12 combination decreased by 0.36% compared to Plain-URHC using ultra rapid hardening cement. This indicated that the watertightness of the mortar was increased by the incorporation of the bio polymer. In the compressive and flexural strength tests, the strength decreased as the amount of bio polymer increased. The incorporation rate of the maximum bio polymer satisfying the KS F 4042 standard was determined to be 12%. In addition, the bond strength of the mortar produced with biopolymer was higher than that of Plain-URHC specimens, and it was confirmed that incorporation of bio polymer improves bond strength of mortar.

최근 남해안과 제주도 연안에는 5,000톤 이상의 괭생이 모자반이 유입되어 양식장과 조업에 큰 피해를 주고 있으며, 환경훼손 등 사회적 문제로 부각되고 있다. 괭생이 모자반에 존재하는 알긴산은 주로 의약품, 식품 등으로 활용되는 천연 고분자 물질이다. 하지만, 대량으로 활용할 수 있는 수요처가 확보되지 않아 본 연구에서는 괭생이 모자반을 활용한 바이오 폴리머를 구조물 보수용 폴리머 모르타르에 활용하기 위한 연구를 수행하였다. 응결특성 평가 시험에서는 바이오 폴리머가 12% 혼입된 L0BP12 배합은 합성폴리머만 혼입된 L12BP0 배합보다 종결시간이 최대 20%증가하는 것을 확인하였다. 흡수율 시험에서는 LOBP12 배합이 초속경 시멘트 배합인 Plain-URHC보다 0.36% 감소하는 것으로 나타나 바이오 폴리머 혼입으로 모르타르의 수밀성이 증가하는 것을 확인하였다. 압축 및 휨강도 시험에서는 바이오 폴리머의 혼입이 증가할수록 강도가 감소하는 경향을 나타내었고, KS F 4042 기준을 만족하는 최대 바이오 폴리머의 혼입률은 12%로 결정되었다. 또한, 재령 4시간 기준 부착강도는 Plain-URHC시험체 보다 모두 향상되었으며, 1 MPa 이상을 확보하여 바이오 폴리머의 혼입이 모르타르의 부착강도를 향상 시킬 수 있는 것을 확인하였다.

Keywords

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