PSI - Issue 84

Alessandro Vari et al. / Procedia Structural Integrity 84 (2026) 975–982

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Experimental validation of the CAM-Bridge ® system was conducted at the DiST laboratories of the University of Naples Federico II. The results corroborated the system's capability to 'sense' service actions and self-balance in response.

4.2. Material Characterization: Duplex Stainless Steel for Maximum Durability The system addresses criticalities such as Stress Corrosion Cracking, fatigue, and difficulty of monitoring over time, by replacing traditional harmonic steel with Austro-Ferritic (Duplex) Stainless Steel, a material widely adopted in offshore applications. Comparative analysis reveals a specific design trade-off: • Mechanical Strength vs. Ductility: Although Duplex steel exhibits lower ultimate strength than harmonic steel (approx 900MPa vs approx 1800MPa), the adopted resistant cross-section and superior ductility compensate for this reduction. • Durability and Fatigue: Duplex offers superior corrosion resistance in aggressive environments and excellent behavior under combined corrosion-fatigue • Maintainability: . Intrinsic material passivation eliminates the need for injected protective sheaths, rendering the tie-rod "naked" and guaranteeing total visual inspectability and re-tensioning capability. Deviators are also manufactured in Duplex steel to ensure electrochemical potential homogeneity and durability of the entire assembly. 4.3. Joining and Tensioning Technology: The T-CAM ® System The T-CAM ® System, a patented joining and tensioning solution, manages the state of coaction. Operating with the MultiMaterial Tensioning System machine, the device applies a controlled preload to "closed-loop" strips. Its operating principle relies on a concentrated plasticity friction pulley, binding strips of various materials (metallic, polymeric, FRP) by adapting to their specific constitutive curves (  -  material). An irreversible motion mechanism (worm screw) prevents accidental locking relaxation while permitting operational reversibility for future tuning.

(a) (b) Fig. 7. (a) T-CAM ® device. This mechanism allows for the locking of any material type without stress loss or relaxation, while ensuring full re tensioning capability.; (b) The MultiMaterial Tensioning System: the machine designed for the T-CAM ® . It features three modified Torsen differentials to apply four identical torque values to the four T-CAM ® worm screws (patent pending). The engineering of the T-CAM ® device leverages Additive Manufacturing (metal 3D printing) to realize complex stainless steel geometries optimized for strength-to-weight ratio and mechanical coupling precision.