Two problems of Tianjin pre-consolidation marine soft clay have been studied through large numbers of tests. One is the structure of soil; the other is elastoplastic model. The structural strength coefficient is led into for the first time

the relationship between microstructural quantitative parameters and mechanical parameters is established. A new kind of constitutive model is proposed to estimate the stress-strain relationship with the changes of structure and so as to offer a new channel for the structural model research and actual application of marine soft clay.