There is a significant variability of salinity level in sensitive marine clays (SMC), which will produce an important impact on the development of mechanical characteristics in stabilized SMC. The influences of salt content (NaCl salt: 3, 10, and 20 g/L) on mechanical properties evolution of cement-stabilized SMC under different curing time (1, 7, 28, 60, and 90 days) have been experimentally investigated and modeled. The results indicate that the strength and modulus increase constantly with time but the time rates decrease. Meanwhile, the apparent improvement of strength and modulus at early age (up to 7 days) is observed. Higher NaCl content can bring a larger strength gain to stabilized SMC after same curing time and the enhancing effect of high salt contents (10 and 20 g/L) becomes more obvious with the extension of curing time. Whereas, the enhancing effect of high NaCl content on modulus is limited compared with strength. Further improvement provided by excessive NaCl salt (20 g/L) is not as effective. In addition, the predictive models have been established to quantitatively evaluate the evolution of mechanical properties in stabilized SMC with different NaCl contents. The capability of developed models has been demonstrated through the good agreement between simulated and experimental results.

Sensitive marine clays (SMCs) often pose considerable problems in the construction of embankments for transportation structures. In this study, extensive mechanical, microstructural, and monitoring experiments were carried out to evaluate the evolution of mechanical properties of SMCs stabilized via Deep Mixing Method. The results indicate that unconfined compressive strength and secant modulus increase with curing time. A significant improvement in mechanical properties is observed at early ages. Higher binder contents produce higher mechanical properties after same curing period. However, excess binder content does not provide significant improvement effects. The addition of ground granulated blast furnace slag (GGBFS) results in higher mechanical properties after long-term curing, and the enhancing degree is more evident with a higher proportion of GGBFS. But the situations are reversed at young age due to the retarding effect of GGBFS. These observations are also supported by results of physical properties, mercury instruction porosimetry, suction monitoring, and X-ray diffraction analyses. In addition, predictive models are established based on elastic-plastic theory and binder hydration model. The developed models are implemented in COMSOL Multiphysics and validated against experimental results. A good agreement is observed between experimental and predicted results which confirms the ability of developed models to predict the mechanical characteristics.