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The article considers information modeling an emergency impact in the study of the stability of a digital architecture building to progressive collapse with the help of a local destruction simulator using the finite element method. A non-linear processor was used, the calculations were performed by the step-iterative method with automatic step selection. When calculating a digital architecture building for progressive collapse, a technique in a quasi-static formulation was used. Measures were developed to effectively counter the emergency. Since the placement of stiffness floors in the current regulatory documentation is advisory in nature, the need to install outrigger floors in relation to a digital architecture building was studied. The concept of a building of digital architecture of a complex shape in the plan was developed. To determine the most loaded rod element of the calculation model, the calculation of the frame of a unique building was performed at the stage of normal operation. At the 2nd stage, this element was switched off from work, and a computational model was obtained for simulating an emergency. As a result of a series of numerical experiments, taking into account various scenarios of emergency impact on the frame of a digital architecture building, a constructive scheme of a unique building with outrigger floors was developed. The unique building resulting from shaping will have a low weight skeleton, taking into account the use of innovative materials. The collaboration of digital technologies and innovative materials will allow the construction industry to move to a completely new level of development.

The article studies the operation of building frame structures with outrigger floors, taking into account seismic effects. The object of the study is a monolithic reinforced concrete frame of the building. The studies were carried out using the modern Lira SAPR software package, which implements the finite element method. Dynamic calculations were performed for several models with different design solutions for outrigger systems and their location. The study of the effectiveness of the decisions made was carried out based on the results of the spectrum of frequencies and periods of natural oscillations. Based on the results of dynamic calculations, two constructive solutions were chosen with higher frequencies and shorter oscillation periods compared to the original model. A study was made of the effect of outrigger floors on the stress-strain state of the building frame. Based on the results of the calculation, conclusions are drawn and recommendations are given for the design of earthquake-resistant buildings.

The behavior of soils in the foundations of buildings and structures, as well as in ground structures and massifs, is formed under the influence of force (surface and volume) and physical (temperature, humidity, etc.) influences. However, if mathematical modeling of force impacts in ground environments can be considered a completely solvable task today, then we consider such a statement premature in relation to physical impacts. The peculiarity of physical impacts is that they can be both the cause of forced deformations and the cause of changes in soil properties. The ground environment with creep properties, which is under both force and physical influences, is considered. The systems of equations of mechanics of a deformable solid for a triaxial stress state and a differential equation of thermal conductivity are used. Within the framework of the model of a linearly deformable continuous isotropic body, mathematical modeling of physical impacts in ground media with creep properties was performed. In a quasi-elastic formulation, a solution is obtained for an unlimited soil massif with a flat surface under the action of a plane -parallel heat flow. In the absence of force influences in a quasielastic medium for deformations from physical influences, we have the usual equations of elasticity theory. The solution obtained for an unlimited soil massif allows the calculation of stresses taking into account creep caused by temperature fluctuations on the surface in it.

There exists an opinion that the modern numerical methods allow to solve practically any problem in mechanics. But it should be noted that both analytical and experimental methods, as before, are urgent, and exactly a complex of methods develops the mechanics of deformable rigid bodies. The statement of a problem in displacements for some possible cases of equivalent substitution of loads allows to formulate necessary and sufficient conditions of existence of an analogy presenting the effect of a forced deformation in the form of the sum of surface and volume forces, the effect of volume forces in the form of the sum of surface forces and forced deformations, the effect of surface forces in the form of the sum of forced deformations and volume forces. The substitution of volume forces for surface loads and forced deformations allows to extend the use of experimental methods and often to solve through an experimental-and theoretical approach the problems, which cannot be solved through other methods. The obtained results are a considerable step in the development of one of the approaches combining experimental, analytical and numerical methods of solution of linear problems in mechanics of deformable rigid bodies.

Polemicizing with the existing opinion that modern numerical methods allow to solve practically any problem of mechanics, it should be noted that analytical and experimental methods still are relevant, and a complex of methods leads to development of mechanics of a deformable solid body. At present one of the most important directions of development of mechanics of a deformable solid body is creation of the approaches that allow to combine organically great computing opportunities of modern supercomputers with experimental methods of the material and design research. In engineering practice at production of designs and products incompressible materials are widely used. Assessment of their durability requires detailed studying of deflected mode caused by action of various loadings and forces. For a solid body from incompressible material, using the resolving equations set of mechanics of a deformable solid body, at action of the compelled deformations of a general view, volume and superficial forces conditions of equivalence are established. It is shown that the known solutions are special cases of the established equivalence conditions. The efficiency of the analytical solution of a three-dimensional task on the rotating disk from incompressible material is shown by the method of equivalence of effects.

In order to determine the deformation of the base, the shrinkage of the structures erected on them, as well as to study the strength of the bases, it is necessary to determine the stresses in the soil massif. The stresses in the soil massif from the action of the structure are superimposed on the existing stresses in it from the action of its own weight, taking into account the excavation during the development of the pit. Therefore, the paper considers the stress-strain state of the ground base with a trapezoidal cutout under its own weight. It is shown that the effect of the own weight of the ground base with a trapezoidal cutout can be replaced by the fictitious action of the ball tensor of forced deformations and external load. At the same time, the previously known methods of replacing the own weight of the soil base by the action of fictitious surface forces, existing in the presence of rigid restrictions, are special cases of the solutions obtained in this work. In modern conditions, in relation to the total amount of accumulated professional knowledge, the volume of active information resources is increasing, and construction practice is constantly enriched with new experimental and theoretically sound accurate knowledge.

The article considers the question of physical modeling of stresses in a compound rotation body of a complex form with a complex loading distribution. According to the similarity parameters, the stresses, deformations and displacements caused by the volume forces are reduced proportionally to the similarity scale for geometrical dimensions which complicates their direct modeling with the use of the models made from conventional epoxy materials. The general methods of study of stresses and deformations usually register them with an inadequate sensitivity. On the basis of the independence principle, the initial problem is presented as a superposition of two problems. In the first (uniform) problem, the stresses in a rotation body caused by centrifugal forces are simulated through the standard “freezing” method. For the solution of the second (non-uniform) problem, the “freezing” of stresses is carried out in the model domain corresponding to the centrifugal forces acting there, and, at the room temperature, the models in their natural state are glued to the model, and the “annealing” of the compound model is performed. The components of radial, tangential and axial stresses at the outlines as well as the cross-sections of models have been obtained through the methods of normal translucence and of numerical integration of the equilibrium equation.

The article considers the use of tuned mass dampers in high-rise construction for significant acceleration and amplitude of vibrations of the upper floors under dynamic wind influences. The susceptibility of people to accelerations in high-rise buildings and possible means of reducing wind-induced fluctuations in buildings are analyzed. The statistics of application of tuned mass dampers in high-rise construction all over the world is presented. The goal of the study is to identify an economically attractive solution that allows the fullest use of the potential of building structures in high-rise construction, abandoning the need to build massive frames leading to over-consumption of materials.

The development of computing techniques to analyze underground structures, buildings in high-rise construction that would fully take account of the conditions of their design and operation, as well as the real material properties, is one of the important trends in structural mechanics. For the territory in high-rise construction it is necessary to monitor the deformations of the soil surface. When high-rise construction is recommended to take into account the rheological properties and temperature deformations of the soil, the effect of temperature on the mechanical characteristics of the surrounding massif. Similar tasks also arise in the creation and operation of underground parts of high-rise construction, which are used for various purposes. These parts of the structures are surrounded by rock massifs of various materials. The actual mechanical characteristics of such materials must be taken into account. The objective property of nearly all materials is their non-homogeneity, both natural and technological. The work addresses the matters of building nonhomogeneous media initial models based on the experimental evidence. This made it possible to approximate real dependencies and obtain the appropriate functions in a simple and convenient way.

The authors carried out the modeling of weighing and filtration forces in the “dam-foundation” system through the methodology of modeling of piecewise-potential volume forces based on the equivalence of effects. They considered a uniform “dam-foundation” system with a drainage structure. The depression curve is taken as a broken line, therefore the filtration flow causes the influence of weighing and filtration forces on the part of this system. The modeling of the effect of filtration forces (which are potential ones) is performed by the method of the equivalence of effects. The experimental studies showed that the effects of the filtration flow at the level of the drainage structure were considerably weaker than those at the level of the foot of the dam. The effects by both the weighing forces and the filtration ones with the given domain configuration considerably reduce the compressive stresses in the foot of the dam at its upstream face caused by the effect of the dam mass, which makes worse the static work of the dam.