Introduction. When the footing is embedded in loose clayey soils, buildings may settle down for a long period of time. The projected settlement period is of great importance for the design of foundations designated for such soils. Therefore, the approach to describing the process of foundation settlement must be considered as rheological. This article addresses the setting of and a solution to the problem of interaction between a long pile and surrounding multilayered and underlying soils with account taken of the rheological properties of the surrounding soil body. The creep process is considered with account taken of stabilization. Materials and methods. Linear problem setting is considered. The analytical method is employed to present a solution. The rheological stabilization parameter is used to describe the creep process. Results. An expression is derived to determine the reduced shear modulus for the multilayered soil body. The relationship between the value of the force applied to the pile toe and the time is derived with regard for the rheological stabilization parameter. Analytical solutions are enforced by graphs in the article. Graphs describing the relationship between pile settlement, the force applied to the toe of the pile, passing through alternating soil layers, and the time are provided for various values of viscosity and the variable parameter of stabilization. Conclusion. Solutions, obtained by the co-authors, are used to perform the preliminary identification of displacement of long piles and surrounding multilayered underlying soils. The rate of stress changing underneath the pile toe depends on soil viscosity. The rheological coefficient of stabilization has a major effect on the time of pressure stabilization underneath the pile toe, as well as the time of the pile settlement stabilization. Dependencies, derived in this article, make it possible to project the future settlement pattern.

Introduction. The overwhelming majority of construction areas are characterized by difficult engineering and geological conditions, represented by the presence of weak soils at the base. There are construction sites on which a large thickness of fill soil is observed. In these conditions, designers apply: soil consolidation, soil reinforcement, significant deepening of the underground part of buildings, etc. This article presents the formulation and solution of the problems of interaction of reinforced concrete piles with weak soils, as well as the interaction of soil piles with bulk soils as part of a pile-slab foundation, which allow one to determine the reduced deformation modulus and the bedding value. Materials and methods. To describe the change in shear stresses depending on depth, a law was adopted in the form τ(z)=τ0е–αz. The solution is presented by analytical and numerical methods. The results obtained were compared by the analytical solution of the problem with the results obtained in the PLAXIS 3D software package. Results. Regularities of the distribution of the total load on the pile-slab foundation between the pile field and the grillage have been obtained. The analytical solutions in the article are supported by the graphical part, performed using the Mathcad program. Numerical simulation of the problem was carried out in the PLAXIS 3D software package. The dependence of the settlement on the load, calculated by analytical and numerical methods, is shown. An expression is obtained for defining the stresses in different sections of the pile shaft and under the grillage slab. The theoretical and practical aspects of the construction of crushed stone piles are considered. The theoretical substantiation of compaction of bulk soils with crushed stone piles using a special technology is given. A dependence is obtained for determining the reduced modulus of deformation for bulk soil mass reinforced with soil piles. Conclusions. Comparative evaluation of the results of solutions obtained by analytical and numerical methods showed good convergence. The solutions obtained can be used to preliminary determination of the settlement of piles as part of a pile-slab foundation. Selection of the optimal ratio of the pile length and its diameter allows the most effective use of the bearing capacity of the pile. For bulk soils, reinforced with soil piles, it is possible to select the optimal reduced modulus of deformation by varying the pitch of the soil piles.