The article presents an analysis of the main methods of processing building structures, that contribute to the preservation of the strength characteristics under aggressive environmental influences, as well as the basic principles for calculating the parameters of cleaning materials with free abrasives.
Keywords: Free abrasive, particle, aggressive environment, dynamic impact, machining parts, probability estimate, contact patch, packing square, trajectory of movement, purification rate
In this review article high-rise construction is considered, factors affecting the choice of a constructive system of a building are given. The shell (box-shaped) structural system is described in detail. The advantages and disadvantages of this structural system are listed.
Keywords: high-rise building, structural system (CS), shell (box-shaped) system, horizontal load, stiffness, stability, bezreskosnaya grille, diagonal grille, column, strapping beam, diagonal connection
In article results of the analysis of method of calculation of flat plates of girderless floors are considered on breakdown according to the Russian and foreign design codes are considered. The analysis of the received results demonstrates that in the considered calculation procedures on breakdown similar settlement models are used and identical power factors are considered. Namely the pressing-through effort and the bending moments operating in two planes. Taking note of the moments in various techniques is carried out in two ways. The first way – tangent tension is entered into settlement model. And each technique offers the form of an epyura of tangent tension. The second way – introduction to a condition of durability of the empirical coefficient considering influence of the bending moments. Approach to purpose of geometrical parameters of a settlement (critical) contour is not identical. Contours of different techniques differ in a form and the sizes. And the difference of the sizes is very considerable. It is established that work of knot of interface of girderless flag with a column is studied yet not fully and additional researches on generalization of calculation procedures are required.
Keywords: reinforced concrete, girderless floor, breakdown, working height of section, transversal armature, pyramid of breakdown
The article is devoted to the comparative analysis of the construction and operation of buildings of traditional shape and round shape in the plan. Given data on material costs in the operation of buildings of different shapes.
Keywords: shaping, round buildings, energy efficiency, square buildings, building shapes, heating, thermal protection
This article analyzes the stress-strain state of exploited reinforced concrete crane beams in order to identify the causes of abnormal damages. Also, the degree of influence of the revealed damages on safety and operational fitness was assessed.
Keywords: crane beam, technical condition, operational availability, defect, durability, damage, inspection, discretization, stress-strain state
The reorganization of existing coatings of public buildings into the “green roof” technology is possible in cases of the generation of an extensive type of green roofing system and, extremely rarely, of an intensive type. To clarify to the above, the load from the green roof of the extensive type in a water-saturated condition on the bearing part of the structural system of the building is 80 ... 100 kg / m2 with a substrate thickness of not more than 0.07 ... 0.15 m. Therefore, in most cases the introduction of this type of green Coverage in public buildings of the existing buildings is feasible.
Keywords: green roof, thermal resistance, strength of parts of the structure, functional zone, limit states, construction, technology and organization of construction
" The article presents research on the problems of construction and design of buildings and structures in the permafrost of Russia. Based on the research work, the principles of construction on permafrost soils are formed. It is shown that the design and construction of buildings and structures can be carried out, provided that the foundations of the soil remain frozen during construction and during operation, and in cases where the soil necessarily becomes thawed during construction or during operation buildings and structures."
Keywords: construction, design, permafrost, soil, foundation, structures, the Far North, climate, soil, building, structure
A comparative analysis was made of the evolution of the development of facade glazing systems in the design of public buildings both abroad and in Russia. It has been established that both abroad and in Russia are characterized by the appearance of buildings with continuous glazing, the production of glass and double-glazed windows of a new generation: with magnetron application of heat-reflecting coatings and with energy-saving characteristics. The shape, size, placement of the glazed surfaces of the facade were determined by the climatic conditions, economic and scientific-technical development of the countries.
Keywords: Facade glazing, translucent facades, Bauhaus, Le Corbusier, stained glass, cold-formed glass, cold facade, exhaust facade, external natural factors
The article deals with the transition from corrugated plates and shells to smooth structures of equivalent rigidity. An expression for the potential deformation energy of an infinitely small element of an equivalent smooth shell and formulas that establish a connection between internal forces and generalized deformations of a corrugated structure are given. A review of the formulas for the equivalent stiffness of the corrugated shell during bending, presented in the works of various authors, is carried out. In order to select the dependencies that provide the smallest error when replacing the corrugated shell with a smooth one, a numerical experiment is performed in the LIRA finite element complex. A corrugated plate hinged around the contour under the action of a uniformly distributed projective load is considered. The calculation of the structurally orthotropic construction is performed numerically by the finite difference method. It is also established that the monograph of S.G. Lekhnitsky contains an incorrect formula for the moment of inertia of a sinusoidal corrugation.
Keywords: corrugated structures, plates and shells, finite element method, finite difference method, orthotropy, equivalent stiffness
The article deals with modern design and architectural planning decisions made in the design and construction of high-rise buildings. The scale and the scientific and technical level of the project represents a unique and first used in the practice of high-rise construction. The article analyzes the basic design decisions, a comparison with international practice and the best design solutions of skyscrapers in the world.
Keywords: high-rise unique building, stability, load-bearing systems, modeling, progressive collapse, structural system, outrigger, skyscraper, column, core of rigidity, strength, reliability, horizontal load
Progressive collapse - or, in particular, an understanding of the mechanics of this phenomenon and the development of ways to consider it in the framework of structural design - can be regarded as a relatively new topic in building science. The article describes the background to the emergence of this topic, ranging from local examples of the collapse of buildings and ending with the well-known collapse of the World Trade Center. Analyzed the latest world research in this area and revealed inconsistencies in the requirements of regulatory documentation and the real work of the building frame in case of progressive collapse
Keywords: progressive collapse, durability, steel frame, multi-storey buildings, connections stiffness, ductility
The article presents data on the effect of external composite reinforcement of reinforced concrete columns on their deformation properties. It is established that the results of calculations of the reinforced samples according to the deformation norms in force have significant discrepancies with experiment. Based on the analysis of the results of experiments, proposals have been introduced into the normative calculation of deflections, which take into account the type and percentage of composite reinforcement and ensure good agreement between the experimental and theoretical data.
Keywords: concrete, reinforced concrete, composite material, carbon fiber reinforced plastic, external reinforcement, deformations, deflections, compressed elements
The paper presents the characteristics of the leading types of media facade constructions on the market, on the basis of the analysis of which the prospects for the introduction of technology into the urban space were evaluated. The article also describes the main types structural and architectural solutions that determine the rationality of the use of a particular type of media facade.
Keywords: media facade, cluster media facade, framed media facade, frameless media facade, modular media facade, LED, architectural lighting, LED screen, media facade design, interactive facade
As is known, the oil refining industry with each year significantly adds to the growth and pace of construction of various enterprises. In the processing of crude oil, you must use a variety of equipment and materials. One of such materials is tube furnaces, which are used for the production from petroleum feedstock - motor gasoline and other products (kerosene, gas oil, diesel oil), including raw materials for the chemical industry (ethylene, propane, butane).For a long time, Customers applied directly to the factory to obtain steel structures. With the introduction of the "Safety Rules PB 03-605-03" the situation has changed. The author presents an individual design of CM (metal structures) to a tank filled with a liquid or gaseous substance.
Keywords: oil refining furnaces, metal frame, tube furnaces, oil feedstock, chemical industry, design
The article describes the main problems of implementation of energy-efficient technologies in the construction sector. The key parameters affecting the energy efficiency of the building, ways to minimize energy losses.
Keywords: Increase of energy efficiency of buildings, minimization of energy losses, energy efficiency class of the building, economical consumption of energy resources
The article discusses the method for calculating beams with corrugated walls as three-layer structures of equivalent rigidity. The derivation of resolving equations for a one-dimensional finite element of a three-layer beam is given. A hypothesis is introduced that the shelves fully perceive normal stresses, and the wall only works on shear. When obtaining the basic equations, forced deformations are taken into account, which may include creep deformations, temperature deformations, shrinkage deformations, etc. The solution of the test problem for a beam hinged at the ends under the action of a load uniformly distributed over the length is presented. To control the reliability of the results, a finite element analysis was performed in a three-dimensional formulation in the LIRA software package. Shelves of the beam are modeled by flat triangular shell finite elements, and the wall is modeled by rectangular shell FE.
Keywords: corrugated wall beam, three-layer beam, finite element method, equivalent rigidity, stress-strain state
Light steel thin-walled structures are considered as elements of modern building erection technology. Domestic and foreign regulatory documents governing the use and design of structures made of thin-walled steel profiles are presented, and obvious advantages and operational disadvantages are indicated.
Keywords: construction, metal structures, light steel thin-walled structures, thin-walled beams, energy efficiency
The method of parametric modeling and design based on the example of a building is studied, the architectural image of which is a set of circular helical and cylindrical surfaces defined by coordinates through functions of the corresponding surfaces in the SAPPHIRE software. Alternative methods for specifying surfaces in the SAPPHIRE PC, AutoCAD with subsequent export to the LIRA PC for engineering calculations of the frame of the building for various combinations of loads by the finite element method are presented. The object of the study is a 360-meter-high building with a hardness core in the form of a cylindrical shell of revolution. The height of the floor is 3 m. Around the rigid shell there are three circular helical surfaces that "rise" in a spiral upward along with the core of rigidity to a mark of 360 meters from the level of the ground floor. One of the most universal ways to create a surface is to specify it through a formula, because you can easily change the shape and appearance of the surface without manually editing the geometry of the model in the drawing. The development of the parametric architecture calls for the creation of new approaches to the calculation of unique buildings and structures, the improvement of software complexes that implement the finite element method, and the appearance of new varieties of finite elements with curvilinear boundaries.
Keywords: parametric architecture, surface, shape of the object, shell, curve, model, geometry, program, formula surface, helical surface
The article provides an overview of the main methods for increasing the energy efficiency of buildings. The main causes of heat loss in the building are revealed. The ways of solving the problems of energy consumption of new objects are shown: installation of alternative energy sources, improvement of thermal insulation of enclosing structures, installation of high-efficiency ventilation with heat recovery, use of energy-saving windows. The legislative base and state programs stimulating energy-efficient construction in our country are considered. A study was made of modern methods of building buildings, allowing to reduce energy and resource costs
Keywords: energy efficient buildings, energy resources, heat insulation, heat loss, geothermal heating, solar collector, energy saving windows
The article deals with the effectiveness of high-strength concrete for the design of concrete columns on the example of 20-storey residential building in Rostov-on-Don. The results of the ground floor columns calculations for different types of concrete strength are presented. The columns are presented in two variations. The first variation is 600x600 B25 from the second underground floor to the tenth floor and 500x500 B25 from the eleventh to twenty-fifth floor. The second one is 500x500 B60 from the second underground floor to the seventh floor, 400x400 B60 from the eighth to the eleventh and 400x400 B25 from the twelfth to the twentieth floor. The analysis of the study results showed the technical and economic efficiency of the use of high-strength concrete (in particular, concrete class B60) due to increasing the strength characteristics of the compressed elements. This is also due to reducing the cross-sectional size and weight of the columns, saving reinforcement, causing a reduction in the cost of elements as a whole.
Keywords: high-strength concrete, compressed elements, construction of tall buildings, columns, Lira-SAPR, calculation of structures
The article deals with the problems of using structural systems with outriggers for high-rise buildings. The analysis of various designs is carried out, the features of their work are specified, the advantages and disadvantages are identified, the areas of their application.
Keywords: high-rise building, structural system, outrigger, skyscraper, column, core of rigidity, strength, reliability, horizontal load, aerodynamics
The article considers the use of renewable energy sources in construction in general and in high-rise unique buildings. Such an approach will allow to design and build buildings in which integrated renewable energy sources can be harmoniously entered into all aspects of construction. This is especially true for high-rise buildings. With the implementation of energy-efficient technologies, the main drawback - high energy consumption - will be cut off. The article analyzes non-traditional sources of energy, such as wind, solar, land, water and biomass. The relevance of their application in construction and influence on all aspects of the project is proved: town-planning, functional, space-planning, architectural and artistic, constructive and engineering.
Keywords: renewable energy source, high-rise building, bioenergy, solar energy, wind energy, aerodynamics, energy-efficient technology, architectural and artistic appearance, planning solution, optimal shape of the building.aerodynamics
The paper deals with statically determinate and statically indeterminate reinforced beams of a rectangular cross-section of bimodule material loaded with a uniformly distributed load. Since for heterogeneous materials, the elastic modulus for tension and compression are different, the work aimed to study the influence of different boundary conditions in statically indeterminate beams on SSS. It is shown that the magnitude of the maximum normal stresses is less than the stresses found without taking into account the bimodule nature of the beam material, both in statically determinate and in statically indeterminate beams. The maximum normal stress and maximum deflection decrease with the transition to a statically indeterminate beam from a similarly statically determined beam by replacing the supports. The method used in work makes it possible to clarify the calculation of strength and rigidity, taking into account the bimodule nature of the material of the reinforced beams, and also to select the optimal fastening of the beams that ensure the bearing capacity of the structure with material saving.
Keywords: reinforced beam, heterogeneity, bimodule material, stress-strain state, normal stresses, deflection, statically indeterminate scheme, bearing capacity, strength, deformability
the article presents the ways of implementation of the strategy focused on the optimization of the process of heat transfer of solar installations, with the applied in their device combined heat exchange panel of aluminum profile elements tightly crimping copper tubes with coolant. Based on the comparative analysis of the two configurations of this device, the methods of heat transfer intensification from the absorbing surface to the working medium in flat-type solar collectors are proposed
Keywords: energy saving, efficiency, optimization, heat transfer, heat capacity, heat exchange panel, heat exchange, solar installation, solar collector, alternative energy sources
An actual problem of the lack of green spaces in modern cities is considered. Some ways of applying gardening in the structure of the building are suggested, which can solve the indicated problem. The most detailed consideration is the reception of horizontal external landscaping, examples of domestic and foreign experience are given.
Keywords: Green architecture, green spaces, vertical landscaping, atrium landscaping, horizontal outdoor landscaping, house-garden decoration of building facades, roofs in operation