Abstract
Large amounts of waste shells have been produced each year from shellfish raising industries located in Korean costal areas. Due to the limited space for the waste shell disposal, the related environmental problem has been a serious issue. It is believed that using the waste shells as a source of aggregate for mortar, concrete or bricks can be a good solution. In this research, possibility of utilizing waste shells as an aggregate of mortar is investigated. Waste shells of manila clam, cockle, clam, sea mussel, and oyster were properly crushed, sieved, and sorted to meet the requirements of the grading of standard fine aggregate. After that, the waste shells were used as partial and total replacement of the fine aggregate, and their absorption and 28-day compressive strengths of mortar were measured. In general, replacement of waste shells increased the absorption and decreased the strength. However, one specimen with cockle increased compressive strength as replacement ratio increased. Mortar with cockle of 50% and 100% replacement showed higher compressive strength than that of control mortar. This increase of compressive strength was found to be affected by the strong interfacial bonding properties of the cockle and a cement matrix.
국내에서는 많은 양의 패류가 생산되고 있으나, 이로 인해 발생하는 대량의 패각을 처리하는데 많은 어려움을 겪고 있다. 따라서 본 연구에서는 이러한 패각을 대량으로 처리하기 위하여 건설재료로서의 가능성을 평가하고자 한다. 모르터의 잔골재를 패각으로 치환하여 흡수율, 압축강도를 측정하고 계면결합 형태를 관찰하였다. 대체적으로 패각의 치환율이 증가함에 따라 흡수율은 증가하였으며, 압축강도는 감소하였다. 예외적으로 꼬막 패각을 치환한 모르터는 치환율이 증가함에 따라 압축강도가 증가하였다. 패각 치환율의 증가에 따른 흡수율의 증가 및 압축강도의 감소는 패각 주위에 발생한 다공성 때문인 것으로 파악되었으며, 꼬막 패각을 치환한 모르터는 패각과 시멘트 입자간의 계면결합 형태가 양호하였기 때문에, 오히려 강도가 상승한 것으로 판단된다.