Effects of High Curing Pressure on the Unconfined Compressive Strength of Cement-Stabilized Bottom Sediments with High Water Content

Reusing dredged sediments as cement-stabilized fill material offers a sustainable solution for high-fill construction projects, particularly in regions with limited land resources and strict environmental regulations. Nonetheless, the curing pressure from their weight heavily affects these materials’ mechanical properties. This research examines the impact of high curing pressure on the stress–strain behavior, unconfined compressive strength (UCS), and stiffness properties of cement-stabilized dredged sediments containing high moisture levels. Laboratory experiments were conducted under controlled conditions, varying initial water content, cement dosage, and curing pressure. Experimental results demonstrate that initial water content and cement dosage are pivotal in determining the material’s strength, regardless of curing pressure. Curing pressure enhanced peak stress and stiffness while increasing brittleness, resulting in a 41.7% increase in secant modulus for specimens cured under elevated pressure. A novel strength prediction model incorporating a curing pressure correction term was developed to quantify material behavior accurately. Microstructural analysis revealed that curing pressure improved material performance through physical densification and chemical activation, enhancing mechanical properties. This study lays scientific groundwork for the optimal design and application of cement-stabilized dredged sediments in large-scale construction projects, addressing the challenges of high water content and high-fill applications.