Seawater and sea sand concrete (SWSSC) filled ultra-high performance concrete (UHPC) tube (SFUHPC tube) column is a cement-based tubular composite column, which combines the excellent compressive strength and toughness of UHPC and lateral confining action from fiber reinforced polymer (FRP) hoops. The novel composite system has the potential to be used in marine engineering. The aims of this paper focus on evaluating the seismic performance of SFUHPC tube columns for being designed in costal and marine engineering. A series of low-cycle reversed lateral loading tests were conducted on five relatively large-scale specimens. FRP hoop volumetric ratio, compressive strength of filling SWSSC, and the types of FRP bar were selected as test parameters in this investigation. The failure modes, hysteretic responses and effects of main parameters were studied and discussed. SFUHPC tube columns exhibited flexural failure mode without visible spalling of the UHPC cover. It is noteworthy that the limit plastic drift ratios of all SFUHPC tube columns exceed the specified limits (0.02) in accordance to the rare earthquake requirement in seismic design code. The current study reveals that the proposed composite columns have acceptable ductility and relatively reliable lateral resistant performance for being used in the marine engineering. From the point of view of seismic performance, filling high strength SWSSC in UHPC tube is acceptable for the proposed composite system.

海水和海砂混凝土（SWSSC）填充超高性能混凝土（UHPC）管（SFUHPC管）柱是水泥基管状复合柱，结合了UHPC的出色抗压强度和韧性以及纤维增强聚合物的侧向约束作用（FRP）篮球。新型复合系统具有在海洋工程中使用的潜力。本文的目的集中在评估在沿海和海洋工程中设计的SFUHPC管柱的抗震性能。在五个相对较大的样本上进行了一系列的低循环反向侧向载荷测试。在本研究中，选择FRP箍筋体积比，填充SWSSC的抗压强度以及FRP筋的类型作为测试参数。故障模式 研究并讨论了磁滞响应和主要参数的影响。SFUHPC管柱表现出弯曲破坏模式，而UHPC盖没有明显剥落。值得注意的是，根据地震设计规范中的罕见地震要求，所有SFUHPC管柱的极限塑性漂移率都超过了规定的极限（0.02）。当前的研究表明，提出的复合材料柱具有可接受的延展性和相对可靠的抗侧向性能，可用于海洋工程。从抗震性能的角度来看，建议的复合系统可以在UHPC管中填充高强度SWSSC。值得注意的是，根据地震设计规范中的罕见地震要求，所有SFUHPC管柱的极限塑性漂移率都超过了规定的极限（0.02）。当前的研究表明，提出的复合材料柱具有可接受的延展性和相对可靠的抗侧向性能，可用于海洋工程。从抗震性能的角度来看，建议的复合系统可以在UHPC管中填充高强度SWSSC。值得注意的是，根据地震设计规范中的罕见地震要求，所有SFUHPC管柱的极限塑性漂移率都超过了规定的极限（0.02）。当前的研究表明，提出的复合材料柱具有可接受的延展性和相对可靠的抗侧向性能，可用于海洋工程。从抗震性能的角度来看，建议的复合系统可以在UHPC管中填充高强度SWSSC。