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The territory of Russia extends from West to East for more than 10 thousand kilometres. Recently, this land has become of strategic importance on the international arena. The future development of Russia and its international situation will largely depend on the timely development of these territories. The development of infrastructure in permafros...
Citations
... The study was carried out using the SCAD software and computing complex based on the finite element method. Comparative theoretical studies of the stress-strain state of wooden and aromawood beams are carried out on the basis of the results of automated and manual calculations in accordance with the current standards [3][4]. ...
The article suggests the use of glued reinforced wooden beams with increased load-bearing capacity. The beam is provided with reinforcing elements in the grooves, namely, in the lower zone – prestressed flexible bundles made of composite, and in the upper zone – steel rods. The analysis of structural behaviour of the beam and the location of the reinforcing elements, the calculation of the bearing capacity of beams and evaluation of the effectiveness decision on material and Flexural rigidity. Composite rods can be prestressed to increase the efficiency of the reinforcement and increase the beam stiffness and load-bearing capacity. Installation of reinforcing elements along the line of action of the main tensile stresses in a wooden beam creates tension in them, which allows the use of flexible bundles and leads to a decrease in the complexity of their installation in the lower grooves, and, therefore, reduces the complexity of manufacturing a wooden beam as a whole.
... Together, this gave a great impetus to the development of the construction of large-span buildings and structures. The use of large-span structures makes it possible to maximize the load-bearing qualities of the material and obtain light and economical design schemes [3][4]. ...
The development of engineering and design, the emergence of new materials (steel, concrete, aluminum, etc.) stimulated the emergence of new types of large-span structures. The structures became lighter, this made it possible to increase the size of the overlapping area. The use of large spans is due to the operational and architectural requirements in public buildings (markets, train stations, stadiums, concert and sports halls). In industrial buildings, large spans are subject to technological requirements. The space freed from supports, covered with a large-span structure, gives the building an emotional and plastic expressiveness. The use of large-span structures makes it possible to maximize the bearing qualities of the material and thereby obtain light and economical coatings. Reducing the mass of structures and structures is one of the main trends in construction. Less weight means less material, less material to be mined, processed, transported and installed.
... Special recommendations should be given at the stage of design and construction of metal structures for large-span unique buildings and structures. Due to the scale of the structure, safety issues are raised, namely measures to avoid progressive collapse due to collapse in accidents [3][4]. It is also worth noting the need for technical monitoring at all stages of construction, and in the future, and operation. ...
According to modern standards, unique buildings and structures include buildings whose spans exceed 100 meters, with successful approbation in practical application, or spans over 60 meters with new design solutions, which require the development of new special calculation methods and the creation of physical models. Unique buildings include objects with a permanent number of people of more than 500, and periodic more than 1000-10,000 people, including people who are near the structure. The reliability of design solutions is confirmed by analyzing design schemes with subsequent assessment of methods and means of performing calculations. It is also necessary to observe, in order to study, the results of calculations for the strength and stability of the spatial system of a structure, to compare the data of theoretical materials with experimental ones obtained as a result of checks.
... Timber structures are lightweight structures, the use of which is one of the most important directions in construction on the way of increasing and increasing the efficiency of the speed of construction production [3][4]. ...
This article examines the operation of structures made of solid wooden beams and composite glued beams of two types, consisting of different types of wood. The object of the study was a beam structure, which is a homogeneous slab resting along a contour of constant stiffness under the action of an external load. The calculation of structures made of glued beams of rectangular cross-section has been performed. The calculation is based on the finite element method, analysis of the main methods and approaches for the optimal design of spatial structural structures/The main unknowns are the displacements and rotations of the nodes of the design scheme, based on this, the idealization of the structure is embodied in a form adapted to the use of this method: this system is presented in the form of a certain set of bodies of a standard type, which is attached to the nodes.
... To solve the considered problem is rather on a graph G find loaded n disjoint paths whose total weight max (under a total weight of the system of tracks is proposed, following (2) to understand a minimum of the weights of the arcs of these paths). Found the way, and it will set the optimal set sequence of stages in the restoration of railway facilities [13,17]. ...
The article considers an approach to solving the problem of finding the optimal option for the work teams to carry out a complex of restoration works at railway facilities destroyed as a result of an emergency. An approach to solving this problem is proposed, based on the methods of graph theory, fuzzy set theory, and mathematical programming. The proposed approach is illustrated by a meaningful example.
In this exploratory study, an integrated electrode consisted of multi-walled carbon nanotubes (MWCNT) and urease enzyme (Ur) was used to conduct electro-catalytic oxidation of urea. The electrode was fabricated by sequential depositions of different layers of MWCNT, platinum metal, and Ur on ITO glass using mainly casting techniques. The enzyme layer was first utilized to hydrolyze urea to ammonia molecules, which was then supplied to the catalytic oxidation reaction as fuel. By doing so, the electrode was able to induce electrooxidation with a current density of 3.2 mA.cm−2 at 0.55 V obtained at urea concentration of as small as 0.1 M along with a good linearity of r2 = 0.9831.
The article contains the search and analysis of the rational form of internal type of composite reinforcement of the single-span beam with 2 walls made of steel. The existing methods of manufacturing for composite materials are considered, the assessment of the possibility of their usage for the manufacture of composite elements, having an opening in cross section are made. Calculations of a number of models in the software-complex Ansys are made, with the subsequent analysis of the obtained results. 4 variants of possible forms of internal type composite reinforcement are considered. The increase in the load bearing capacity of the reinforced sections of the hybrid-type beam is estimated according to criterion of ultimate normal stresses in the relation to the basic variant of the steel beam made without any reinforcement.
In the article search of the rational composite plate forms, increasing stability of steel walls of the single-span hybrid beam structures are performed. The analysis of critical situations, due to which loss of stability are possible, with an assessment of existing technical solutions preventing dangerous situations, are made. An alternative option for increasing stability of the steel parts of the beam with usage of composite plates is proposed. Two types of calculations for searching of dangerous zones of possible buckling are made: analytical and software calculation in the Ansys software-computing complex. Possible forms of losing stability of the steel wall of the one-span beam are analyzed. Based on the calculations results the search of rational form of reinforcing composite plate according to criteria of the ratio of sufficient growth of the system stability to the lowest consumption of composite material are made.
The article is devoted to the space-planning and structural solution of dome structures for the regions of the Far North. The article analyzes the predecessors of these design solutions, emphasizes important aspects of bioarchitecture, the possibility of widespread use of this style; disclosed existing problems. A solution for the construction of quick-assembly structures is proposed, which allows widespread use of the developed solutions for the active development of the Far North regions. The possibility of manufacturing planning and structural elements is proposed. However, in life, most of the settlements in the northern part of Russia are built up with wooden barrack-type houses, or typical dull five-story panel houses, clearly not meeting climatic conditions, which are quickly destroyed under the influence of climatic conditions. The task of our work was to develop a large-span design solution with a high bearing capacity, reducing wind and snow loads, having collapsible properties, allowing, if necessary, moving the structure, which is important for the regions of the Far North. The optimal solution for Northern construction is a dome, one of the oldest structures formed by a spherical surface of revolution.
