Controlling of the Mechanical Behavior of Mass-Stabilized Organic Clay with Various Binders

The mass stabilization method has been successfully used to improve organic soft soils. Prior laboratory investigation is essential for the technique’s success. The laboratory molding methodology for mass stabilization simulates in-situ conditions with high water content and preloaded specimens. However, the laboratory step becomes unfeasibly time-consuming when pozzolanic binders are used. Furthermore, the literature reveals knowledge gaps regarding higher preload levels and the influence of porosity and binder content on the mechanical response of laboratory mass-stabilized specimens. To address these gaps, this study employs a commercial binder, type III Portland cement (CEM-III), and an alternative ternary binder (TB) composed of carbide lime (CL), ground granulated blast furnace slag (GGBS), and CEM-III for the mass stabilization of organic clayey soil. The effects of binder content, preload level, and binder type on the mechanical response and microstructure of mass-stabilized soil were analyzed. The statistical model used to support the results highlighted the strong influence of binder content and preload level, which control the final porosity and the mechanical response of mass-stabilized soils. The results demonstrated that higher preload values (36 kPa) can improve mechanical behavior even without increasing the binder content, making the process more economical. Additionally, the study demonstrated an important combined effect of high binder content and preload, maximizing the strength of the stabilized soil. The TB demonstrated higher strength (with a maximum value of 2857.2 kPa) and stiffness (with a maximum value of 414.3 MPa), as evidenced by the less porous microstructure observed in SEM images. A regression model was developed to define equations for estimating the mechanical response based on preload and binder content.