Deformed scheme for design of piles injected into predrilled holes

A method is proposed for the calculation of piles injected into predrilled holes with allowance for their flexibility and possible initial curvature of the pile's axis. The stability of the pile is assessed in the soil mass. An example is cited for the calculation of foundation strengthening by inclined piles. Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, Nos. 4–5, pp. 8–12, July–October, 1998.     

Determination of dynamic bed parameters for calculation of torsional oscillations

A computational scheme is proposed for determination of the stiffness coefficients of embedded noncircular foundations subject to torsion. Calculations are performed in accordance with the method of boundary integral equations (BIE), and empirical formulas are developed for calculation of stiffness coefficients, including formulas with consideration given to loss of contact between a portion of the lateral surface of the foundation and soil. Assumptions relative to determination of damping coefficients are given. A comparison is made with experimental data on the oscillations of experimental foundations, and preference is demonstrated for the proposed method of calculation. Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 6, pp. 9–14, November–December, 1998.     

Calculation of landslide danger and maximum landslide pressure by the variation method

The authors give a calculation of soil pressure carried out at Giprorechtrans by the RUST computer program, and compare it with analogous calculations by the SL VAR program, which was described in a previous issue of our journal. “Giprorechtrans” joint-stock company. Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 2, pp. 31–32, March–April, 1994.     

Calculation of the temperature of permafrost cooled by small-diameter heat siphons

An effective method is proposed for calculation of the temperature fields beneath structures built on fills cooled by a system of small-diameter (as compared with the depth of embedment) horizontal vapor-liquid heat siphons. A comparison is made with results of computer-assisted mathematical modeling by the finite-difference method. Translated from Osnovaniya Fundamenty i Mekhanika Gruntov, No. 5, pp. 22–25, September–October, 1995.     

Bearing capacity of piles in clayey soils from calculations and field tests

The bearing capacity of piles, calculated from the flow index of clayey soils and results of dynamic tests, is compared. The flow-index calculation was performed with consideration of its confidence interval for separate layers of soil 2 m thick. A significant difference is indicated in bearing-capacity calculations in an example of piles 6 and 8 m long. __________ Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 3, pp. 26–29, May–June, 2006.     

Refinement of the engineering method used to calculate foundation settlements and tilts of high-rise buildings

A procedure for calculation of bed settlement beneath a slab foundation, which was previously formulated in conformity with schematic representations of regulatory documents and which takes into account the shape of the foundation, the load distribution, and inhomogeneity of the bed is presented. For simulation of the load on the bed of a high-rise building, a diagram of its deformation beneath the lower surface of a “rigid plate” is proposed. A successive-approximation procedure based on use of equilibrium equations of the slab is developed for calculation of the settlement. Determination of the settlements and tilts of the foundation of a specific high-rise building are discussed as an example. __________ Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 6, pp. 2–7, November–December, 2007.     

Limiting-state design of permafrost beds for global warming

The stability of permafrost beds is examined from positions of reliability theory. A method is proposed for calculation of the safety factor; use of this method makes it possible to account for random variations in air temperature and global warming of the climate in the limiting-state design of beds. Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 5, pp. 21–23, September–October, 1997.     

Application of Finite-Element Method to Investigate Interaction between Slide-Prone Soils and Piles

An analytical scheme using the finite-element method is proposed for interaction between slide-prone soils and piles in single-row anti-slide structures. Results are presented for calculation and analysis of the stress-strain state of slide-prone soils interacting with the piles. __________ Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 4, pp. 8–12, July–August, 2005.     

Calculation of suffosion deformations in saline soils

A method is proposed for the calculation of nonuniform settlements of a single rigid foundation on an inhomogeneous bed of saline soils, including those in which inclined layers exist. Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 5, pp. 11–13, September–October, 1995.     

Design of deep massive foundations for lateral loads in multilayer soils

A simplified design method, which takes into account the actual characteristics of the deformability of each layer of soil in determining foundation displacements and pressures on the soil, is proposed; this makes it possible to avoid errors in estimating the stability of the soils that interact with the foundation. The results of the calculation of a sunken shaft by the exact and approximate methods are compared. Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 6, pp. 12–14, November–December, 1995.     

Effect of local loads on the character of soil pressure on productive structures

Conclusions An approximate analytical solution has been obtained for the law of soil pressure distribution in a PS in the presence of a local load on the surface. The solution is characterized by the following conditions: 1. The effect of the local load leads to formation of four zones in the plane of the PS. Different rules are applied for calculating stresses in each of these zones. 2. In the presence of local loads, horizontal pressure on the PS should be determined only from the combined effect of the load, soil weight, and soil cohesion since the principle of superimposition is not applicable under these conditions. 3. Unlike existing methods of calculations using the Coulomb's theory, the solution provides for a common method of calculation for all locations and sizes of the loading area. Here, error due to the use of the proposed approximate dependences does not exceed 2–3% in comparison with computer calculated numerical solutions. 4. Comparison of the methods of calculation used in design practice showed that Klein's method [3] yields reliable results for wide loading areas of b>2 while the method in SN-RF 54.1–85 [6] yields almost reliable results for narrow loading areas of b<1. For wide loading areas the latter method underestimates the pressure. For narrow loading areas, the methods in [3] for a concentrated and distributed load are at variance with one another and yield differing results while the method in SNiP 2.09.03–85 [7] is unreliable in all cases and yields underestimated results. Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 4, pp. 24–27, July–August, 1991.     

A method of calculating the compression deformation modulus of sandy and gravelly soils

A method based on use of Hardin's homogeneous model is proposed for calculation of the deformation modulus of noncohesive soils. Completely satisfactory correspondence between computed and experimental values of the deformation modulus of sands is demonstrated. Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 4, pp. 2–5, July–August, 1994.     

Assignment of boundary conditions and order of fem calculations for shallow structures

Characteristic features of the assignment of boundary conditions for the design of shallow structures are addressed. A computational procedure based on the finite-element method (FEM) is developed on the basis of a scheme with “removable” stresses. The following are characteristic features of the procedure: staged pattern of the calculation, which is constructed in a manner so as to account for various influences exerted on the deformation of the mass by stresses acting prior to the opening of a working and the additional stresses that develop during this opening, as well as consideration of technogenic changes in the properties of the soils. The computational procedure is accompanied by examples with various initial and boundary conditions. Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 6, pp. 14–17, November–December, 1996.     

Design features of soil-concrete structures built by means of jet geotechnology

The need for the design of soil-concrete structures with simultaneous planning of their installation using jet geotechnology is cited, since the physico-mechanical characteristics of these structures will depend on parameters of the production process. A procedure is developed for analytical calculation of physico-mechanical characteristics of these structures, and the procedure employed for their installation with allowance for the properties of the in-situ soils; this will make it possible to optimize parameters of the production process. __________ Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 4, pp. 25–27, July–August, 2007.     

Calculation of bed strength for various loading schemes

A computational procedure and values of the coefficients M_g, M_q, and M_c are given for calculation of foundation beds for various, loading schemes. Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, Nos. 4–5, pp. 28–31, July–October, 1998.     

Numerical modeling of freezing and swelling processes in the “foundation-bed” system

A method of modeling the process of soil swelling as the bed freezes through is investigated. An algorithm for FEM calculation and basic characteristic features of the developed software are presented. The potential of the software is illustrated in examples of the solution of a number of problems. Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 5, pp. 6–9, September–October, 1994.     

A design method for seepage barriers with allowance for the initial filtration gradient

A method is presented for calculation of the basic parameters of an anti-seepage “wall” with allowance for the initial filtration gradient of the filler material. The case of plane-radial seepage through a contour “wall” of the perfect and imperfect type, which is constructed by various modifications of the “wall-in-the-ground” method and using kinematic jet energy, is discussed. Computational analytical relationships and working equations for a number of special cases are derived in general form for the schemes under consideration. A software package, which makes it possible to make a rational projection of structural parameters of the “wall” and determine the position of the depression curve ahead of the “wall,” is developed. Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, Nos. 4–5, pp. 37–42, July–October, 1998.     

Bearing capacity of hollow piles sunk in leader holes

Correction factors that account for the reduction in the resistance of hollow circular piles sunk in leader holes are obtained as a result of experimental investigations. A program is developed for calculation of the bearing capacity of these piles from penetration data. Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 3, pp. 19–22, May–June, 1996.     

Method for calculating bed deformations of buildings near deep excavations

An experimental-analytical method is presented for calculation of the settlements of buildings in the vicinity of deep excavations with allowance for their weight and stiffness. A building near an excavation is treated as a semi-infinite beam subject to a uniformly distributed load. A solution is obtained for the equation describing the bending of the beam modeling a building on strip foundations placed on a bed represented by a Winkler model. __________ Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 6, pp. 2–6, November–December, 2006.