Geotechnical characteristics and consolidation properties of Tianjin marine clay

Tianjin, which is located on the west shore of the Bohai Sea, is part of China\'s Circum-Bohai-Sea Region, where very weak clay is deposited. From the 1970s to the early 21st century, Tianjin marine clay deposits have been the subject of numerous geotechnical investigations. Because of these deposits\' geological complexity, great depositional thickness, high water content, large void ratio, excessive settlement, and low shear strength, the geotechnical properties of Tianjin marine clay need to be summarized and evaluated based on various in situ and laboratory tests so that Tianjin can safely and economically sustain more infrastructure in the coming decades. In this study, the properties of Tianjin marine clay, especially its consolidation properties, are summarized, evaluated and discussed. The focus is on establishing correlations between the geotechnical property indexes and mechanical parameters of Tianjin marine clay. These correlations include the correlations between the water content and the void ratio, the depth and the undrained shear strength, the liquid limit and the compression index, the tip resistance and the constrained modulus, the plasticity index and the ratio of undrained shear strength and the preconsolidation pressure. In addition, the primary consolidation properties of Tianjin marine clay, such as the intrinsic compression line (ICL), sedimentation compression line (SCL), compression index, Cc, coefficient of consolidation, Cv, and hydraulic conductivity change index, Ckv, are evaluated and discussed. A secondary consolidation property, i.e., the secondary compression index, Ca, is also investigated, and the results show that the ratio of Ca/Cc for Tianjin marine clay can be used to calculate Ca in secondary consolidation settlement predictions.