The paper presentsexperimental results and an analysis on the features of crack formation and crack opening in beams of solid and hollow cross sections made of high-strength reinforced concrete at a complex stress state - torsion with bending. It has been established that one or more spatial cracks can form at quantitatively comparable ratios of torque and bending moments in the considered structures in the zone of torsion with bending. The obtained experimental values of the crack opening width for beams of solid and hollow sections significantly differ from each other. The maximum opening of progressing cracks along which the destruction of the experimental structures occurred was observed not along the axis of the tensile reinforcement, but at a distance of about two diameters from this axis. The obtained results of experimental studies make it possible verification and comparative analysis of the calculation models proposed for calculating the crack resistance of rod reinforced concrete structures under torsion with bending.

Strength parameters that determine the ultimate load-bearing of a bent reinforced concrete element along an oblique section from the action of a transverse force are clearly random. In order to construct the probability density distribution of the ultimate transverse force, it is necessary to find the parameters of this distribution. If we assume that the distribution of the ultimate transverse force is close to the Gaussian law, then it suffices to know the mathematical expectation and variance of this probability density distribution. The probabilistic characteristics of the ultimate transverse force in a reinforced concrete bending element are constructed. The ultimate transverse force is a nonlinear function of the strength of concrete and reinforcement, which are considered as random, normally distributed quantities. It is shown that the nonlinear function of the ultimate transverse force can be linearized by expanding in a Taylor series near the mathematical expectations of the tensile strength of concrete and the yield strength of the reinforcement with sufficient accuracy for practical calculations. The distribution density of the ultimate transverse force in this case can be considered obeying the normal law.

In this work, an experimental study of the welded concreted joint on the shear force was carried out. The test was carried out only for shear, since the main static purpose of vertical butt joints of panels is to ensure the perception of shear forces arising in the joints when the mating walls work together. The object of the study was a fragment of wall vertical connection 125 a series of large-panel residential buildings, the thickness of which was 160 mm and the total height is 550mm. In result of experimental research defined stress-strain state of vertical butt joints and proposed approximating the dependence of the deformation of the weld joint from shear forces. The test results can be used in the calculation of load-bearing systems of largt-panel buildings taking into account the nonlinear compliance of welded joints.

The aim of the paper is to illustrate using of analytical surfaces, i.e. surfaces, which can be given by vector, parametric or explicit equations, in real structures, i.e. in parametric architecture. Parametric architecture is a unique style in which such concepts as sculpture, mathematics, structural mechanics, and architecture are interconnected. Parametric design in contrast to other styles has a relationship with mathematics. This paper continues a series of works of the authors devoted to application of analytical surfaces in architecture and building, devoted to investigation of influence of researches on the geometry of surfaces on design of large-span shell structures and to application of interesting geometrical forms for unique erections. In the paper, a photo of only one erection having this form illustrates every analytical surface, which can be seen in forms of real erections. It turned out that only 42 of the 600 surfaces described in the literature were used in the World. For those who are interested in the mathematical side of design of surfaces, their computer modeling, or more detailed information about real structures in the form of the surfaces in question, a voluminous bibliography are given.

Systems based on thin-walled galvanized profiles and effective heaters are widely used as wall fencing at present stage of development of enclosing structural systems. Wall fencing based on one-element assembly is most widespread. At the same time new solutions in the form of panels assembled from prefabricated elements are appeared. The latter in addition to technological advantages in comparison with the one-element assembly wall fencing have increased bearing capacity and rigidity. This article presents a constructive solution of a self-supporting wall panel based on cassette profiles and deck profiled sheets, combined into a single spatial structural system. The purpose of the work was to scientifically justify and experimentally confirm the operability of a new structural solution of the panel based on the cassette profile. The object of the study is a wall fence (panel) based on such profiles. Research methods: numerical and analytical methods, experimental studies of the full-scale model, graphical analysis. The article consists of two parts. The first part is devoted to the description, analysis and justification of the design of the wall panel and to the study of the deformed state of the cassette profile and the assessment of the resistance and stiffness of the wall panel based on the calculation method. The second part reflects the results of experimental studies of the panel and its components, and also implements a design procedure based on tests.

The construction of a mathematical model describing the effect of flooding on the stress-strain state of a thin flat spherical shell of a titanium layer loaded with an equidistributed load using a nonlinear model is considered. By A.A. Treshchev. The load is adopted in such a way that the deflections of the shell are small. Fix of the shell is hard. An algorithm was developed to solve this class of problems. A practical solution was produced by the two-step method of sequential perturbation of parameters using the MatLab and Maple application software package. To derive and solve the system of resolving differential equations, the finite difference method was applied. A comparison of the results obtained with the results of the classical theory.

The results of the study of the damaged condition of the multi-storey building of the service and household unit of the Kursk NPP are presented. The analysis is carried out taking into account the engineering-geological structure of the base and the peculiarities of the construction of the frame. Studied existing damage and deformation of load-bearing and enclosing elements identified their causes, chief among which are nervnoe-tion of sediment foundations, caused by resting one row podkolonnik on the base plate adjacent buildings industrial buildings, as well as the sequence of construction of adjacent buildings. The developed method of strengthening the frame of a multi-storey building, based on the re-support of a number of columns on an additional independent ribbon Foundation, located between the extreme and middle axes, is described. The calculated analysis shows the effectiveness of the proposed reinforcement structure, while additional design solutions are proposed to protect the building from progressive collapse

Fuzzy logic is a useful tool when assessing the existing reinforced concrete structures. The introduction of expert system in assessing the technical condition of the existing structures built on the fuzzy logic represents a transition to a new and higher-quality level for the survey of constructions sites. The paper presents the principle of development and implementation of expert system for assessment of the damages of the existing structures. The process is based on the algorithm in which the input data (crack width and propagation, residual strength of materials, amount and condition of the steel reinforcement, deflection, corrosion level et al.) and information collected at each phase are processed and interpreted in order to define the successive step of the procedure. As a result, it is seen that the assessment of the existing building with precast concrete elements with usage of the proposed fuzzy system is in compliance with the estimation of the qualified experts.

The article presents the methods for reliability analysis of CFA (Continuous flight augering) piles with under-ream on settlement criterion. The presented methods of reliability analysis take into account the limited statistical information about the controlled parameters in the design mathematical models of limit states. That increases their practical significance (fewer control soil samples are required for testing), but reduces the informativeness of the reliability analysis results. The paper also presents methods for reliability analysis of CFA piles in the presence of complete (full) statistical information for individual parameters that increase the informativeness of the reliability analysis results. The article deals with numerical examples of reliability analysis for CFA piles with under-ream at the lower end. The paper is aimed at fulfilling the requirements of Russian Federal Law No. 384-FZ and Interstate standard GOST 27751-2014 "Reliability of structures and foundations" for the design and inspection of pile foundation with CFA piles.

Social and psychological factors that can affect human well-being in the formation of sustainable development of the Voronezh agglomeration are considered. The article substantiates the relevance of the development of urban recreational spaces, adjacent territories, transformation and modernization of existing buildings in the context of solving the problems of urban development. The requirements to the assessment for each characteristic indicator affecting the psychological state of a person are given: the density of building, the height of construction, the situation with yard spaces, landscaping.

The study is based on the identified archival and printed sources, field studies of the author, which allow more reasonably reconstruct the architecture of the lost and preserved fragments of noble and merchant estates in the territory of the border region of Russia. The scientific novelty of the study is associated with the author's expeditions to identify signs of existence and full-scale survey of a number of surviving manor complexes, which had not previously attracted the attention of researchers. Of particular importance is the identification of archival and printed sources that allow more reasonably reconstruct the figurative and material structure of the lost elements of noble and merchant estates. The special significance of the complex research work is due to the possibility to fill in the gaps in the study of important pages in the history of national and regional Russian culture, reflected in the formation of regional features of construction techniques and imagery of architectural ensembles of estates of the Kursk region.