The influence of a threshold gradient of water flow in soft clays on consolidation behavior has been gradually recognized. However, the consolidation theory with consideration of a threshold hydraulic gradient and rheological characteristics has rarely been reported in the literature so far, and especially the analytical solution for this problem has never been studied. In view of the deficiency in consolidation theories, the governing equation for one-dimensional consolidation of the clay with consideration of the threshold gradient and rheological characteristics is developed on the basis of Terzaghi's theory for one-dimensional consolidation. An analytical solution for the governing equation is obtained by the method of Laplace transform. The analytical solutions for one-dimensional consolidation derived so far considering either a threshold gradient or a rheological model are all special cases of the solution derived herein. Based on the solution proposed in this study, the influences of the threshold hydraulic gradient and different rheological models on consolidation behavior are investigated. The results show that the influences of the ratio of the threshold gradient (i0) and the thickness of clay layer (H) to the load (q0) on consolidation behavior with consideration of rheological characteristic do not evidently change comparing to that under consideration of linear elastic model. The largerRis, the longer it takes for the moving boundary to reach the bottom of the layer, and the larger the ultimate value of excess pore water pressure is, and the smaller the ultimate average degree of consolidation is. Moreover, the condition that the moving boundary reaches the bottom of the layer differs with that with no consideration of rheological characteristic. If the same parameters of different rheology models are adopted, the dissipation curves of excess pore water pressure and the variation of moving boundary with time under different rheology models are almost same at the early stage of consolidation. At the late stage of consolidation, the difference between dissipation curves of excess pore water pressure different rheological models is so little that the influence of different rheological models on the result can be ignored.
