The article is offered refined and simplified methods for determination of non-uniform settlements caused by decompression of soil in the excavation. The results of the calculations executed taking into account the done suggestions and in the program Plaxis are presented. The results of the calculations are compared with the results of experimental observations given in the literature. The influence of the excavation parameters on the non-uniform settlements is investigated. Present a proposal for adjustment of the conditions, which require consideration of soil decompression in the excavation.

This article provides a method of compaction of the soil base by creating a sealing pressure inside the soil massif. Nowadays, in buildings reconstruction, which is accompanied an increase loads on the foundations, in constrained conditions of dense urban development, the question strengthening of bases of foundations is important. The proposed a method of compaction of soil base by creating a sealing pressure inside soil massif is applicable both for new construction and for reconstruction of any objects in dense urban development. It carried out a comparative analysis of results of experimental and theoretical studies of the bearing capacity of piles with different parameters of broadening and compacted zone obtained by the method of compaction of soil base by creating a sealing pressure inside soil massif. Numerical studies to determine the bearing capacity of piles were performed in axisymmetric formulation using Hardening-Soil model. The method of determination of changes bearing capacity of base in depending on the diameters of broadening and compacted zone was carried out on a specially designed stand is presented. The article presents the results of experimental and numerical studies of bearing capacity of bases foundation.

The article proposes a method for determining additional vertical stresses at any point in the massive of expansive soil, which arise from the weight of unmoistened soil outside the soaking area. A comparison of the results of research stress-strain state of expansive soils when soaking from above, obtained by the proposed method, the finite element method and in accordance with current regulatory documents. The proposed regularity of the distribution of additional stresses from the weight of unmoistened soil outside the soaking area in horizontal sections of the flooded zone is confirmed by the results of numerical studies by the finite element method. For a vertical line passing through the center of the flooded zone, the proposed method gives results that are almost identical to the current regulatory documents. The application of this method allows more accurate determination of the swelling surface, taking into account the unevenness of the geological structure, the shape of the flooded zone and stress fields, and determining the forced displacements of the base or equivalent loads when calculating structures interacting with expansive soil. The conditions are determined under which it is advisable to simulate the impact on the building from the side of swelling soil by equivalent loads acting from the base.

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The article considers study of influence of coefficient ksl on subsidence value. In course of study, it was revealed that coefficient ksl, determined according to normative documents of Russian Federation, has a limited scope and does not always lead to sufficiently satisfactory and theoretically justified results. In this article, a range of pressures on the bases up to 500 kPa has been investigated. This range makes it possible to take into account the redistribution of pressures in case of uneven deformations of the base of the foundations. These pressures in some areas can significantly exceed calculated resistance of subsidence soil. When pressure increases more than 500-600 kPa, subsidence decreases due to additional compaction of subsidence soil without soaking due to destruction of structural bonds from pressure value. Therefore, at high pressures on the base, proportion of subsidence deformations in the total vertical deformation decreases and the proportion of deformations caused by the development of shear zones increases. Dependence of thickness of lower subsidence zone on pressure by at different widths of bottom of a foundation are presented. Proposed algorithm for determining subsidence deformation by external load on base, allows to separate subsidence deformation from shear deformation of soil and thus obtain more accurate values of subsidence deformations in entire range of possible pressures on foundation Dependences of subsidence on pressure determined by normative documents and proposed algorithm for different foundation widths are given. A comparative analysis of values of subsidence at different foundation widths is given.

This article proposes a method for determining the nonlinear settlements of the foundation, based on the method of layer-by-layer summation, which allows to determine the settlement of the foundation until the base bearing capacity is exhausted, taking into account the heterogeneity of the geological structure of the soil massif and the presence of weak underlying layers of soil. The recommended equation for determining the coefficient ks is given, which allows you to approximate almost any curve of the dependence of settlement on pressure, taking into account the properties of the soil base, size, shape and depth of the foundation. It carried out a comparative analysis of the proposed method with the results obtained experimentally and other calculating methods.