An Integrated Performance-Based Screening Framework for Fiber-Reinforced Concrete Floating Dock Blocks for Offshore Renewable Energy Applications

Selecting fiber-reinforced concrete (FRC) for thin marine shells is a multi-constraint decision because lower cradle-to-gate global warming potential (GWP) at equal volume may be offset by post-cracking requirements, interface behavior, impact response, or detailing. This study introduces a performance-constrained, multi-evidence screening framework and illustrates it with traceable mechanical, fiber-field, marine-bond, impact, and life-cycle datasets for four self-compacting concrete systems with 90 kg/m3 of industrial and/or recycled steel fibers. Unlike a compensatory environmental–mechanical index, the framework applies simultaneous normalized response constraints, independent interface and component gates, deterministic ranking-sensitivity analysis, and component carbon-parity budgets. Compressive strengths were 60.03–66.10 MPa, whereas post-cracking properties varied substantially. At 80% retained performance, beam work favors I30R60, whereas an additional 3 mm splitting constraint favors I45R45. For a 0.144 m3 panel, I45R45 has 3.89 kg CO2-eq less reported cradle-to-gate GWP than I90R0, corresponding to only 5.50% additional concrete before carbon parity under the source inventory. Results depend on published means and inventory assumptions. The four documented 4.0 m impact tests (one slab per tested composition) illustrate the component gate as a proof of concept rather than a statistically supported pass/fail criterion. Replicated component testing and project-specific verification are required before design qualification.