고전적층판 이론을 이용한 카본튜브의 재료특성 해석과 원형 콘크리트 기둥의 압축강도 향상에 관한 연구

A study on material properties analysis of carbon tube using classical laminate theory and improvement of compressive strength of circular concrete columns

Carbon fiber is a material that has a very high tensile strength and is flexible, so it is easy to manufacture into a desired shape. If carbon fiber is processed into a thin carbon sheet and then a circular concrete column is wound, the compressive strength can be improved due to the confined effect. In this study, the characteristics of multi-layered carbon sheets were identified by applying the Classical Lamination Theory. To directly measure tensile strength and lateral restraint pressure, tensile test and split disk test specimens were fabricated and then material experiments were conducted using a 2,000kN capacity UTM. The lateral restraint pressure of carbon sheet tube was about 5.4MPa and the tensile strength was 3,790Mpa, which is about 9.5 times the strength of steel reinforcing bars. The equation for predicting compressive strength of circular concrete confined by carbon sheet tubes manufactured at various angles was proposed through regression analysis. It is judged that this can be used as an analytical equation that can predict the strength in advance when a concrete column whose bearing strength has been lowered due to an earthquake, etc. is reinforced with a carbon sheet.