### СONSOLIDATION AND CREEPOF SUBFOUNDATIONS HAVING FINITE WIDTHS

Pages 38-52

The authors formulate and solve the problem of consolidation and creep of saturated clay subfoundations exposed to localized loads (the two-dimensional problem formulation). The findings have proven that, if the two-dimensional problem is considered, any excessive pore pressure is concentrated immediately under the area exposed to the localized loading, and it penetrates into the depth equal to 1/2 of the strength of the compressed width. Subfoundation subsidence is caused by both shear and 3D deformations of soil. Besides, the ratio of shear-to-3D deformations reaches 10. Therefore, the authors propose to represent the subfoundation subsidence as the sum of shear and 3D deformations.The differential equation of the filter consolidation, if considered as the 2D problem, is solved using the Mathcad software. The software is used to analyze the isolines of excessive pore pressure at any moment following the loading application. New depen- dence representing the ratio of the changing area of the diagram of the average effective tension to the area of the diagram of the average tension in the stabilized condition is proposed by the authors.In the final section of the article, the authors solve the problem of prognostication of the subsidence pattern for the water saturated subfoundation with account for the shear creep of the soil skeleton. The authors employ the visco-elastic Bingham model characterized by time-dependent viscosity ratios. The authors have proven that in this case the subsidence following the shear load will develop as of the moment of application of the external load pro rata the logarithm of time irrespectively of the process of filtration consolidation.

DOI: 10.22227/1997-0935.2013.4.38-52

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