Floating offshore wind turbines face growing integrity-management challenges caused by coupled corrosion and fatigue in harsh marine environments. Existing digital-twin frameworks are not yet well suited to combine multi-phase degradation physics with dynamic uncertainty quantification for this problem. To address this gap, this paper proposes a probabilistic digital twin framework that integrates sensor data acquisition, multi-physics simulation, and Bayesian inference for corrosion-fatigue prognosis. A three-phase damage evolution model is formulated to represent the transition from corrosion pitting to short-crack growth and long-crack propagation. Operational observations are assimilated recursively to update fatigue parameters and remaining useful life estimates. The framework is demonstrated using the IEA 15 MW reference wind turbine. The updated model identifies the onset of accelerated crack propagation at year 20 and reduces the 95% remaining-useful-life confidence interval from 40.4 years to 3.4 years. A maintenance strategy based on the updated failure probability reduces operational downtime by 58% and lifecycle cost by approximately 64.9% compared with a fixed-interval strategy. The results indicate that probabilistic updating can support more transparent inspection and maintenance decisions for floating offshore wind turbine structures under corrosion-fatigue degradation.

As a core material in modern construction, the early-age properties of concrete have a decisive impact on the safety and durability of civil engineering structures. However, systematic research on the mechanical properties of early-age concrete remains limited, particularly regarding the combined influence of cohesive and frictional properties on the material’s macroscopic mechanical behavior, which has not been thoroughly explored. To address this gap, this paper employs a decoupling method for testing the cohesion-friction mechanical properties of concrete, as proposed in previous work. This method successfully separates the cohesive and frictional properties of early-age concrete, validating its applicability under early-age conditions and obtaining typical failure modes following material performance degradation. Furthermore, by analyzing the evolution patterns of cohesive and frictional properties during deformation and strength development, the synergistic mechanism of cohesion-friction mechanical properties in early-age concrete was revealed. The results indicate that the responses of cohesive and frictional properties to hydrostatic pressure in early-age concrete exhibit significant differences. The reduction in macroscopic shear strength and stiffness is fundamentally attributed to the irreversible dissipation of cohesive strength. Ultimately, the mechanical behavior of early-age concrete gradually approaches that of granular materials without cohesion.

In recent years, the rapid development and proliferation of highways in China have made asphalt pavement maintenance increasingly complex, requiring maintenance management departments to make practical choices of preventive maintenance measures within limited budgets. To improve comprehensiveness, scientific rigor, and the economy of decision-making, the Analytic Hierarchy Process (AHP) was employed to conduct a decision-optimization study of preventive maintenance measures for asphalt pavements. Taking the preventive maintenance project of the Liuzhou North Ring Expressway in Guangxi as a case study, maintenance measures were initially selected through road condition assessment and investigation. A multi-level, multi-objective decision-making AHP model was constructed, including an objective layer, a criterion layer, an indicator layer, and a scheme layer. By comprehensively considering maintenance needs and assigning values to multi-level factors, the weights and priorities of each maintenance measure were determined. The results show that the ranking and weight calculation of measures such as ultra-thin cover, composite seal coat, micro-surfacing, thin layer cover, and seal coat are relatively rational, and the theoretical analysis results are in good agreement with actual needs.