초고성능 콘크리트를 활용한 LNG 탱크의 안전성 및 내구성 향상

초록

This study investigated the feasibility of applying ultra-high-performance concrete (UHPC) on the outer containment of a liquefied natural gas storage tank to improve its safety and durability. For this purpose, normal concrete (NC) and UHPC with three different straight steel fiber specimens (i.e., S65, S97.5, and S100) were fabricated and tested under a four-point bending load at three different conditions (i.e., ambient, cryogenic-AC, and cryogenic-WC) before and after cryogenic exposure to evaluate the effect of cryogenic temperature. Microscopic observation and scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX) analysis were performed to determine cracking and self-healing behavior. The test results indicated that UHPC provided better resistance to crack formation than NC at cryogenic temperature. Moreover, UHPC with the S65 fiber showed the best performance at cryogenic temperature in terms of flexural performance and self-healing capacity. The SEM-EDX analysis confirmed that, after 28 days of water curing, the crack-filling materials were calcium carbonate (CaCO3).

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