## 6 Conclusions
Additionally, for design engineers, the reasonable self-stress value, strength grade, and reinforcement ratio of the SSAWC, the reasonable ratio of the LCSS thickness to pier column diameter, and the established restoring force model proposed in this study can provide a basis and reference for the seismic strengthening design of underwater damaged piers in practical engineering. In future research, the interfacial bonding performance between the filled concrete and adjacent members, the durability of the segment sleeves, and the modular design of the filled concrete and segment sleeves should be further explored. Moreover, additional experimental data and numerical simulations are required to validate the proposed restoring force model for piers strengthened using IPCSAM. Conceptualization, S.S. and Y.S. ; methodology, Y.S. ; software, W.X. and Y.S. ; validation, Y.S. ; formalism analysis, Y.S. ; investigation, Y.S. ; resources, S.S.; data curation, Y.S. and W.X. ; writing--original draft preparation, Y.S. ; writing--review and editing, S.S.; visualization, Y.S. ; supervision, S.S.; project administration, S.S.; funding acquisition, S.S. All authors have read and agreed to the published version of the manuscript. This work was funded by the National 13 th Five-Year Research Program of China (Grant No. 2016 YFC0700706), Traffic Science and Technology Project of Fujian Communication Department, China (Grant No. 201536 and 201716), and the Education and Scientific Research Project for Young and Middle-aged Teachers of Fujian Province, China (Grant No. JAT60044). Not applicable. * [PERSON] and [PERSON] (2003) [PERSON]; [PERSON] [PERSON] External Prestressing Concrete Columns for Improved Seismic Shear Resistance. _J. Struct. Eng._**2003**, _129_, 1057-1070. [CrossRef]
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