수치해석에 의한 LNG 저장탱크용 강관파일 전기방식 설계 최적화 연구

Abstract

For the longer service life of steel pile, cathodic protection is selected sometimes at corrosive environment. The cathodic protection design improvement was investigated in this study. The current demand for cathodicprotection was calculated from the potentiostatic current monitoring of the steel specimen in the deaeratedsoil samples. In this study, the current distribution was studied using the Boundary Element Method (BEM)and the Finite Element Method (FEM) numerical analysis methods. The optimum layout of the anode wasdeveloped and confirmed by numerical analysis. Under the conventional design of the anode, the lengthof the anode hole is same as the pile length. We found that, at the bottom end of the pile, the currentdensity is too high. When the anode hole length was 80% of the pile length, the current consumptionat the end was reduced. The construction cost of anode hole drilling was decreased about 20%, as comparedto the conventional design. Furthermore, the life of the anode materials could be extended by reducingthe current consumption at the end section. Using this approach, the construction cost was reduced significantlywithout any under-protection area on the steel piles.