METHOD FOR DETERMINING CHARACTERISTICS OF FILL-UP GROUND Russian patent published in 2020 - IPC G01N33/24 

FIELD: construction; soil science.

SUBSTANCE: invention relates to construction soil science and can be used in designing artificial bases of foundations of buildings and structures from fill-up clay soil and in agronomy for qualitative assessment of agronomic value of soil by size of soil aggregates. Method for determining characteristics of fill-up ground is in multi-cycle loading-unloading of soil sample in rigid cylindrical chamber with static pressure, initial value of which is matched with pressure at the construction site from transport mechanisms, and the final value is matched with the sealing pressure at the construction site. Registration in each loading-unloading cycle of soil sample of axial deformation of compression at loading and axial deformation of expansion at unloading, end of multi-cycle loading-unloading of soil sample when stable value of soil elastic work coefficient is achieved with allowable coefficient of variation in 6 last loading-unloading cycles and determining moisture content, density and density of mineral soil particles, specific operation of compaction and expansion, volume content in soil of elastically deformable water and water participating in inelastic part of soil deformation, and volume content of mineral particles in soil. Multi-cycle loading-unloading of the soil sample is performed with constantly increasing and constantly decreasing pressure at the rate of not more than 10 kPa/min with recording of pressure values and axial deformations of compression and expansion of soil sample with deformation step of not more than 0.005 mm and time of their development. Speeds of axial deformation of compression and expansion of soil sample are determined by reduced dependence. At pressure p_I and p_I-1, kPa, where p=B_pt, where t is duration of increase or decrease of pressure, min, with rate Bp≤10, kPa/min, and by periodically repeating values, cycles of change of speed of axial deformation are selected compression and expansion of sample, inherent to this soil, and among the characteristics of the soil, the generalized size of the structural elements of the soil compacted in the given pressure range is further determined from the given relationship.

EFFECT: technical result consists in improvement of reliability and accuracy of results of tests of soil sample at multi-cycle loading-unloading, providing increase in number of determined characteristics of soil.

1 cl, 3 dwg