Rheological properties and scour resistance of solidified slurry for offshore wind monopile protection

This study systematically investigates the rheological and scour resistance characteristics of sludge based solidified slurry for offshore wind turbine foundation protection. Employing systematic rotational viscometry and a novel flume testing approach, this research established relationships between slurry composition, rheological properties and critical scour resistance velocity (V s ). The findings reveal that HPMC content exerts the most significant influence on early-stage scour resistance performance. Optimal enhancement performance was observed at 0.3 % HPMC, beyond which further improvements in yield stress did not translate into proportional gains in V s . Sodium silicate effectively accelerated early hydration and enhanced short-term resistance, though its contribution diminished at longer curing times. Although a low water-to-solid ratio markedly improved yield stress, it only marginally increased V s . To capture these interactions, a dimensionless Scour Resistance Coefficient (SRC) was proposed, revealing nonlinear correlations between rheology and scour resistance. The findings provide a practical formulation framework for balancing workability and durability, thereby advancing the sustainable application of solidified slurry in offshore wind monopile scour protection.