Various methods of analyzing the settlements and tilts of building foundations on a natural bed are currently being discussed, and are in practical use. Use of finite-element procedures is most promising for these analyses, and not to mention for analyses of interaction between structures and beds. Engineering approaches that make it possible, even if in approximate form, to account for experience gained from observations of the settlements of constructed buildings and different parameters, which may be difficult to consider in finite-element schemes, however, are recommended in modern regulatory documents [1-3, and others], and are most frequently employed in practical calculations.We are proposing an algorithm for practical computer utilization of a scheme that can be used for settlement calculation, and also a means of accounting for the shape and mutual arrangement of slabs in plan, nonuniformity of loading on the bed and its inhomogeneity, which can be assigned from data of geologicengineering surveys. The algorithm serves the same purposes as for the "KROSS" program for determination of the coefficient of subgrade reaction, which was developed under the guidance of Fedorovskii [4]. The scheme recommended in [1] for determination of the settlement at an individual point of the bed with allowance for the depth of embedment of the foundation is used; stress calculation by the method of "corner points" is optimized; assignment of an arbitrary nonuniform load distribution on the lower surfaces of the foundation slabs is possible; and, a procedure for consideration of actual geologic-engineering information, which makes it possible to avoid the subjective and ambiguous procedure of constructing sections, is employed [5]. This procedure utilizes formalization of the geologic-engineering information presented in [6].Foundation settlements and tilts, and also distribution diagrams of the stiffness coefficient of the bed along the lower surface of the slabs are calculated in the example of a specific building constructed in Moscow with a height of approximately 80 m and an adjacent underground parking garage. The surface of the section is inclined, and the foundation is placed in a pit ranging from 5.0 to 9.5 m deep. The foundation of the upper section is a slab with a thickness h p = 1.3 m, while the underground section, which is adjacent to the upper, is a slab with h p = 0.5 m.As in [4], a system of rectangular coordinates is introduced onto the site plan, and a computational domain is created in the form of a rectangle, which completely covers the system of foundation slabs with An algorithm is proposed for practical implementation of a scheme for analysis of the settlement of building foundations, which has been set forth in modern regulatory documents. Methods to account for a slab with a complex planform, nonuniform loading on the bed, and the actual heterogeneity of the soil bed, which can be assigned directly from survey data, are developed within the framework of this scheme.

The traditional approach to presentation of geologic-engineering information obtained during on-site surveys for a project under design consists in plotting of geologic sections showing assumed boundaries of isolated geologic-engineering elements (GEE), and tables containing computed values of physico-mechanical soil characteristics for each GEE. The indicated data are forwarded to designers in the form of a technical report on geologic-engineering conditions at the inspected site [1,2].In any case, further data preparation for geotechnical analyses, for example, construction of "cores" for zones of the mass that do not fall within the plotted sections, is assumed for such a "standard" content in the survey report. When modern computer programs are used, preparation of some sort should be algorithmized, i.e., sets of values for soil characteristics and other numerical parameters that apply to a point or zone of the soil mass for which the analysis is performed should be "automatically" evaluated on the basis of available information, and transferred to an effective block of the program.In this paper, we propose an algorithm for the preparation and computerized formalization of geologic-engineering data, which takes into account the actual processing of these data and diagramming of the soil mass, which can actually be used in performing geotechnical analyses and incorporated into regulatory documents [2,3]. The soil mass is modeled by a set of "homogeneous" geologic-engineering elements characterized by average and so-called "design" values of soil characteristics. Despite the limited nature of this model, it enables us to resolve the majority of problems that arise in practice relative to analysis of geotechnical systems on the basis of limiting states. As in the procedure previously proposed by the Scientific-Research Institute of Foundations and Underground Structures for evaluation of the "reliability" of geotechnical systems [4], therefore, we will proceed from the indicated scheme in the procedure developed in preparing initial data for computerized geotechnical analyses.A scheme and algorithm are proposed for formalization of information contained in reports on geologic-engineering surveys conducted for the design of buildings and structures. The data are presented in the form of a working base containing required descriptive information on design geological elements, which are written via a special coding, and digital data (hole parameters, roof elevations of geologic-engineering elements (GEE), values of the characteristics of corresponding soil varieties, and so forth). Relationships permitting calculation of the depth dependence of soil characteristics established in the base for any point in plan at the site with respect to the indicated data set are written out and programmed. "Automated" (without nonalgorithmized construction of geologic-engineering sections) calculation of these dependencies determines the adaptation of the proposed approach to computerized geotechnical analyses.Let us denote the e...

The article describes the uniaxial compression tests on rock salt samples under monotonic loading, which were carried out with the synchronous record of changes in thermal radiation and mechanical parameters. A relationship between the nonlinear deformation stages and the features of thermomechanical processes is found. The rate of change in rock stress state is shown to affect the information value of variations in the attendant infrared radiation. The experimental results point out the possibility of using the method in monitoring of the real geomechanical objects.The deformation and failure processes in solids, including geomaterials, are accompanied by the wide electromagnetic spectrum: from radio-wave pulses [1, 2] and infrared radiation [3, 4] to luminescent flashes [5]. The current methods are based on using the mentioned effects, which appear under changes in the state of geomaterials and allow the information of them to be found [6][7][8][9][10][11].To diagnose the stress state of different materials for both research and technological purposes, two well-known thermodynamic effects are applied. They involve the change in temperature of a solid upon varying the first invariant of stress tensor [3,12] and the relationship between the intensity of infrared radiation from a solid surface and the temperature [3,13]. As previously shown [8-10], such approach can become effective for the contactless measurements of elastic stresses in geomaterials.The purpose of the present paper is to consider the possibility for identifying the deformation processes in geomaterials under the wider range of conditions, namely, under the stresses coming to the elastic and ultimate strengths, by measuring the thermal radiation.The experimental stand is shown in Fig. 1. All tests were carried out with the Instron 150LX press, which allows implementing the "hard" and "soft" modes of uniaxial loading and provides the automated and synchronous registration of changes in the mechanical parameters and the corresponding variations in infrared radiation intensity.As in [8-10], RTN-31 is used as the primary infrared radiation detector [14] meant for the contactless measurement of optical radiation intensity in the infrared spectrum of wave lengths. IR radiation detector 1 is fixed approximately at the center of sample 2 at a distance of 0.5-1 cm from its surface. M70P-S3 strain-gage 5 for measuring the changes in the force exerted on a sample is placed between plate 3 and base plate 4. Contrary to bench in [9, 10], the gauging stand includes longitudinal strain indicator 6 embedded into the loading press and located between plate 4 and the moving beam of the press. This gage allows one to obtain the relationships between the longitudinal stress 1 σ and longitudinal strain 1 ε , as well as to define the boundaries between the process stages and test the transitions by using the thermal radiation data.

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