Strength and Dynamic Properties of Cement-Mixed Korean Marine Clays

Deep Cement Mixing (DCM) is the most commonly employed ground improvement method for offshore construction purposes worldwide. Nevertheless, the dynamic behavior of cement-mixed and stabilized clays is almost unknown due to the lack of experimental studies, while seismic concerns regarding offshore structures related to typhoons, tsunamis, or earthquakes are becoming more important. Moreover, very few geotechnical evaluations have been performed to characterize cement-mixed Korean marine clays, while DCM is the most commonly used practical implementation method for soft soil improvement in Korea. In this study, a series of laboratory experimental studies were conducted to obtain the static strengthening and dynamic behaviors and geotechnical engineering design parameters of cement-treated Korean marine clays. The unconfined compressive strength and shear stiffness (G) of cement-mixed Korean marine clay increase with curing time, while different trends were observed for straindependent behaviors (i.e. normalized shear modulus and damping ratio) depending on curing time and binder contents. The static and dynamic geotechnical properties and relationships of DCM treated soft clays obtained in this study are expected to be accepted for seismic considerations and designs of DCM-treated soft clays.