Application and performance evaluation of prestressed cable-stayed systems in large-scale offshore recovery towersOA

The offshore rocket recovery tower is an essential infrastructure for reusable space transportation.To address the lack of design methods and quantitative performance evaluation approaches for prestressed cable-stayed bracing systems under asymmetric and complex loading,this study develops an asymmetric two-stage prestressed cable-stayed bracing system for a large-scale offshore recovery tower with a height of 67 m and plan dimensions of 54 m×70 m.Dual-platform finite element models were established in MIDAS Gen and SAP2000,and 292 full-condition load combinations were analyzed using a nonlinear step-by-step inheritance algorithm.In parallel,a refined Abaqus solid model was employed to verify the core load-bearing joint locally.Prestressing reduced the maximum X-direction deformation under transportation conditions from 263.2 to 222.1 mm,yielding safety margins of 14.6% and 17.5% in the X-and Y-directions,respectively.The stresses in the main structural members were markedly improved―the Q460 truss and beam elements satisfied the allowable-stress limits,whereas the Q355 truss elements remained only slightly above the limit.The local maximum von Mises stress at the inner pulley block joint reached 891.9 MPa,indicating a risk of local yielding.These results demonstrate that the asymmetric prestressed cable-stayed bracing system can effectively enhance the global stiffness and forcetransfer performance of large-scale offshore recovery towers,and that the full-process analytical framework established in this study provides a theoretical basis and engineering reference for the design and performance evaluation of analogous offshore aerospace support structures.