Soil Mechanics and Foundation Engineering

The problem of computational analysis of thin foundation slabs for vibroactive equipment on a soil base is considered. Methods, algorithms, and examples of computations of such structures for loads transmitted from machines with rotating parts in transient and operating modes are given. A numerical–analytical method is used to analyze conditionally infinite slabs. The finite element method and the modal superposition method are used to analyze slabs of finite dimensions. The results show that the use of thin slabs on a soil base for vibroactive equipment offers several advantages and can be used in construction.

The article shows that the use of the normal distribution for statistical processing of the results of mechanical testing of soils, in particular, when determining the bearing capacity of piles in terms of soil, can lead, in case of a small number of tests and the presence of outliers in the experimental data, to an illegal underestimation of the calculated indicator to values less than the minimum values obtained in the tests performed. It is proposed to replace this distribution with a lognormal one that allows avoiding “implausible” conclusions.

Questions regarding the impact of soil stabilization and changes in soil stress-strain state on soil mass reinforcement in response to grout injections are discussed.

The modeling of the "reservoir with oil – system "GET" – soil massif" system for 1392 random trajectories of air temperature, wind speed and snow cover thickness changes for two years is carried out. It is shown that the result temperature distribution in the soil massif has the form of normal distribution.

Results are cited for analytical prediction of the influence exerted on surrounding buildings and structures by the construction of a shallow tunnel installed by the open-pit method. Two sections of the route along the third transportation beltway in the Lefortovo District, for which three-dimensional mathematical models of the construction were developed, are examined. Results obtained indicated the negligible effect of the tunnel's construction on existing buildings and structures, and are in good agreement with data derived from geodetic observations. The condition of the tunnel structures was monitored using monitoring-measuring equipment installed at three sites along the route.