4. By assuming that distortion is coordinative and stress is in equilibrium at the interfaces of columns and soil in composite foundation and that the average consolidation degree in composite model was equal to the one in composite foundation, a three-dimensional composite model was established by effective stress analysis method. The corresponding finite element method is then developed for consolidation analysis of composite foundation.

The formulas for computing mean and deviation of the average consolidation degree of double-layered soil are derived as vertical coefficient of consolidation submitting to Gamma distribution.

In nonlinear consolidation, especially for layered soils, the average consolidation degree defined by settlement, Us is greater than the one defined by effective stress, Up, i.e., the rate of the development of settlement is greater than that of the dissipation of excess pore water pressure.

By using the solutions, the approximate methods so far available for the computation of average consolidation degree of soft soil with partially penetrated vertical drains were compared and discussed in detail, and the consolidation characteristics of soft soil with partially penetrated vertical drains are investigated.

Two kinds of analytical relationship between Uσ and Uε are derived on basis of compression curve of hyperbolic and semi-logarithmic type respectively, and thence a method to predict the coefficient of consolidation for the in-situ soil from the settlement observation is proposed.

penetrability and the change of reference stress(initial stress) along the different depth. Establish a one-dimensional non-linear rheologic consolidation equation by using improved model. Based on the principle of iterative and general analytical solution for one-dimensional consolidation of layered soils, solution of semi-analyticaly method has been developed herein for elastic-viscoplasty consolidation problem of layered ground.

Average consolidation time 77.1 days; completion of treatment 145.6 days.

Average consolidation time 21.8 days; average completion of treatment 46 days.

In this paper, Laplace transformation, initial parameter and matrix method are used to solve one-dimensional consolidation problems of layered systems and general representative solution has been Obtained. For double layer's subsoil calculation formulae are presented. A numerical example is given which approximately agrees with results from finite difference method. From numerical calculation it is shown that the method using a weighted average consolidation coefficient will result in significant error. For...

In this paper, Laplace transformation, initial parameter and matrix method are used to solve one-dimensional consolidation problems of layered systems and general representative solution has been Obtained. For double layer's subsoil calculation formulae are presented. A numerical example is given which approximately agrees with results from finite difference method. From numerical calculation it is shown that the method using a weighted average consolidation coefficient will result in significant error. For sand-drained subsoil, when the sand-drains do not penetrate through the whole soft soil, it is suggested that an equivalent consolidation coefficient may be obtained by means of transforming the three-dimensional consolidation problem into one-dimensional, then calculation is made according to one-diensional consolidation of double layers, so that the continuity problem of pore pressure on the interface between double layers may be solved rather rationally.

In the theorteical reserch field of the three dimensional consolition in soft soil foundation, although a solution to this compound problem has been given by R.A.Barron with the help of the three dimensional parabolic equation under the 2nd type boundry condition, [(l), (2), (3)], yet regretfully, it has not sufficient accuracy. This paper points out the shortage of the Barron's solution and gives an accurate solution to this problem through 1st and 2nd type Bessel function. At the same time, the definiteness...

In the theorteical reserch field of the three dimensional consolition in soft soil foundation, although a solution to this compound problem has been given by R.A.Barron with the help of the three dimensional parabolic equation under the 2nd type boundry condition, [(l), (2), (3)], yet regretfully, it has not sufficient accuracy. This paper points out the shortage of the Barron's solution and gives an accurate solution to this problem through 1st and 2nd type Bessel function. At the same time, the definiteness of the solation is shown。 The author presents the advanced transcendental equation J_o(x)Yj (kx)-Ji (kx) Yo (x)=0, accompanied by a method of solving the /fro point, when k>l. Finally, by using this result, the average degree of consolidation in soft soil foundation can be easily obtained.

In routine design of sand drains, mean consolidation degree and mean strength increase are estimated, using only horizontal coefficient of consolidation. In this paper, it is suggested to compute consolidation degree at any time at any depth of subsoils by use of three dimensional consolidation theory. It was shown that the results estimated by such appproach are more accurate. Some graphs for computation prepared with computer were presented. Finally, two illustrative example by means of such graghs were given....

In routine design of sand drains, mean consolidation degree and mean strength increase are estimated, using only horizontal coefficient of consolidation. In this paper, it is suggested to compute consolidation degree at any time at any depth of subsoils by use of three dimensional consolidation theory. It was shown that the results estimated by such appproach are more accurate. Some graphs for computation prepared with computer were presented. Finally, two illustrative example by means of such graghs were given.