Determination of subsidence of drill-injection piles with controlled broadening

The article describes a modernized design of a drill-injection pile, which allows to perform the whole complex of works on strengthening the foundations of reconstructed buildings without impact, mechanical and dynamic effects. An algorithm is proposed for calculating the subsidence of drill-injection piles with controlled broadening, as well as its comparison with regulatory solutions and experimental data obtained at a construction site in the city of Tyumen. The forecast is given on the changes in the stress-strain state of the soil mass under the building foundation when determining its subsidence. It is shown that the value of subsidence mainly depends on the calculated resistance of the soil mass modified in the process of setting up the drill-injection pile, both on the lateral surface and under the lower end. The analytical solutions presented in the article allow us to more accurately determine the subsidence value, taking into account the changes in mechanical characteristics of soil and residual stresses during the formation of the compacted zone.