A Study on Reinforcing Marine Soft Clay with Marine Recyclable Aggregate Prepared from Seawater, Alkali Activator, and Recycled Particles from Paste Using CT Observation

This study investigated the use of Marine Recyclable Aggregate (MRA), synthesized from Recycled Particles from Paste (RPPs) obtained from construction waste, seawater, and alkali activator (Na2O∙3.3SiO2, NS), for reinforcing marine soft clay. RPP is a laboratory-prepared material used to simulate construction waste. The physicochemical properties of MRA were characterized using X-ray diffraction (XRD), thermal field emission scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), and thermogravimetric analysis (TGA). The results revealed that the key hydration products in MRA are Friedel’s salt (3CaO·Al2O3·CaCl2·10H2O, FS), xCaO·SiO2·nH2O (C-S-H), and CaO·Al2O3·2SiO2·4H2O (C-A-S-H). The formation of these hydration products enables MRA to maintain stability in marine environments. The deformation characteristics of MRA-reinforced soft clay under various conditions were investigated by integrating X-ray computed tomography with triaxial compression tests, allowing for the three-dimensional visualization and reconstruction of the failure process. The application of MRA for soft clay reinforcement in seawater environments enhances the bearing capacity of the clay and provided significant environmental benefits.