Geotechnical issues of investigation of the technical condition of the structure on weak soils according to the boundary element method

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The article considers the controversial issue of the need to take into account the increasing coefficient to the soil deformation modulus obtained on the basis of compression studies for the design of loess frozen soils. It is well known that weak soils can have low bearing capacity and high compressibility, which makes them difficult to construct and operate structures. It is known that in laboratory conditions, the modulus of soil deformation is usually determined by compaction with a static load without the possibility of lateral expansion in a rigid ring. The disadvantage of the compression device is the low accuracy of measurements, which is emphasised by many researchers due to the fact that the friction forces of the soil sample on the ring walls reduce, depending on the moisture content and soil type, the vertical pressure applied to the sample during the test. This leads to a false decrease in the actual value of the soil deformation modulus. To determine the reliability of the two approaches to determining the soil deformation modulus, the settlements of the foundations of grain storage silos on dangerous degraded loess soils were calculated by the numerical method of boundary element (MBE) using an elastic-plastic model, with and without taking into account the soil deformation modulus. It has been found that solving the problems of assessing the technical condition of a building is associated with geodetic and engineering-geological surveys and the analysis of these results, since the stress-strain state of the building-foundation system and the peculiarities of deformation of the soil base depend on them. After all, the problem of protecting a building from rolling is quite relevant. The design or reconstruction of structures on foundations with weak soils (with a deformation modulus E < 5 MPa) is also associated with the problem of ensuring that the calculated deformation values do not exceed their maximum permissible values for the experimental structure. The results of numerical studies are compared with the method of finite element (MFE) calculation and experiment.