The calculation by various methods and comparison of the economic efficiency of the use of metal, reinforced concrete and pipe-concrete columns during the development of the reconstruction project of the production building are considered. A technical and economic comparison is made for the following parameters: the mass of steel and concrete; cost of basic materials; labor intensity and cost of production. Analysis of options for calculating building structures can help in choosing the way to restore the operational reliability and load-bearing capacity of reinforced concrete compressed elements.
Keywords: concrete, pipe-concrete, load-carrying capacity, I-beam column, reinforced concrete, building structures, reinforcement, constant load, strength, operational reliability, deformation
To ensure sufficient strength, stability of buildings and structures, the possibility of their further normal operation, as well as during reconstruction, when it is necessary to increase the loads on existing structures, it is necessary to strengthen the damaged structures. Ways of strengthening and repairing damaged structures of buildings and structures can to a great extent differ both in technical and economic indicators and in the convenience of implementation, so that their proper choice in each particular case is extremely important. The article considers options for strengthening load-bearing building structures and verified computations for load-carrying capacity taking into account additional loads. The technical and economic comparison of the amplification variants in terms of the following parameters is made: the mass of the amplification elements; the cost of the basic materials needed to strengthen; labor intensity and cost of production; labor intensity and cost of performance of works on strengthening. Analysis of options for strengthening load-bearing building structures can help in choosing the method of reinforcing the load-bearing capacity of reinforced concrete bending elements.
Keywords: bearing capacity, reinforced concrete structures, reinforcement, constant load, strength, operational reliability, deformation
The article is devoted to the study of the location of buildings in the city of Rostov-on-Don,with considering the town-planning aspects of planning urban areas. In the process of research, a geoinformation database was created with the criteria for the location of residential buildings in various geological risk zones. As conclusions to the article, an analysis was carried out with the identification of the location of buildings in complex geological and environmental conditions within the city of Rostov-on-Don.
Keywords: Urban construction, density of construction, engineering and geological conditions, territorial planning, geoinformation database
To solve the economic, technical, environmental and social problems of the region, it is expedient to create a regional inter-branch finance and construction forestry cluster (IFSLP). The creation of a regional IFSLP facilitates the most effective use of the integration process in the allocation of investment resources in the region. Cluster education allows: - to create investment attractiveness of the region; - to organize new jobs - to attract young professionals with higher education - to use innovative developments - to increase deductions to the local budget - to clean the forest from dead wood and substandard timber, to generate heat and electricity, - to create a competitive export product.
Keywords: resource-producing complex, regional interindustry financial and construction forestry cluster, innovation, investments, forestry direction, construction materials
This paper discusses features of development of design documents for new construction of motor roads. Lists the main stages of project development from inception of technical specifications for design work to delivery of documentation to the customer. The contents of the project documentation for car winter roads are indicated, with a description of each section. It is important to approach the development of project documentation with special care and responsibility, since sometimes even the slightest mistake can lead to serious consequences during the construction and operation of the facility. At each stage of documentation development, much time and effort is expended, current errors are identified, sections are rechecked, therefore, from preparation an technical design assignment to obtaining a positive expert opinion, it takes an average of 1.5-2 years. Correctly designed project guarantees the safety of people, when they are on the winter road.
Keywords: winter road, design, arrangement of territory, engineering surveys, technical design assignment, section of project documentation, the stages of project development, expertise
The paper considers the actual problem of an assessment of mechanical characteristics of two-layer materials by nondestructive methods (a method of conical indentation). The calculation of the process of indentation into two-layer medium by the finite element method with ANSYS program. The influence of layer thickness on the parameters of the indentation is considered.
Keywords: conical indenter, nondestructive testing, mechanical properties, strength tests of metal, finite element method, hardness, surface hardening
The paper discusses the contemporary technologies for making glass envelopes by way of planar glazing as part of reconstruction of buildings and facilities. It is highlighted that polyvalent multi-layer external walls are considered by many scientists as a mechanism for improving energy efficiency of façade systems. Based on the analysis of the research literature, the authors also note that spider glazing is optimal for two-layered glass envelopes, as it is suitable for use as part of reconstruction of frame and frameless buildings. Adaptive façade systems are suggested to be arranged with the use of brackets having a telescopic glass holder.
Keywords: energy efficiency, reconstruction, glass envelops, adaptive buildings, translucent façade, spider glazing, glass holder
The causes of death of people during a fire, as well as the effect of toxic combustion products on the human body are analyzed. It was found out that the main problem of unhindered evacuation of people from the building is blocking the evacuation routes by smoke. Methods of fighting smoke in a fire are considered and their advantages and disadvantages are determined. One of the ways to solve this problem is ultrasonic coagulation of aerosols with subsequent precipitation. Effective coagulation of smoke in a fire can be provided by a piezoelectric ultrasonic oscillatory system.
Keywords: fire, fire safety, multi-storey public building, toxic combustion products, smoke removal, smoke deposition, high intensity ultrasonic vibrations, ultrasonic radiation, acoustic radiator, piezoelectric ultrasonic oscillatory system
In this article, problems of safety of the exploited structures of the contact network are examined. The types of contact network supports used in the construction of these structures are considered. The features of the centrifuged concrete structure formation, the reasons for the heterogeneity of the structure along the thickness of the annular section and the appearance of cracks are analyzed. There is a physical model, the use of which will allow to modify the structure along the thickness of the annular section due to directed structure formation in the process of concrete with a combined aggregate and fibrous components centrifugal compaction.
Keywords: safety of structures, contact network supports, centrifuged structures, annular cross-section, physical model of the process of compaction of concrete mixture during centrifugation, concrete with combined aggregate and fibrous component
This article describes the definition of the approximating function of deflections of building structures using the method of least squares.
Keywords: the approximation function, the least squares method, the deflections of structures, prediction of deformations, the deformation of the structures
This article deals with the history of the study of engineering-geological conditions of the territory of the Caucasian mineral waters and territory of the sanatorium "red rocks". Technical report provides details on engineering geological research on the site overhaul and reconstruction of the economic bloc, "red rocks"
Keywords: degree, engineering-geological territory conditions, geological structure, mineral water
The lack of standards for the calculation of lightweight thin-walled steel structures allowed low-quality producers to save on production, which endangered the people who exploited such buildings. The appearance of normative documents for the calculation of thin-walled structures entails responsibility for the affirmers of these normative documents. In Russia, such norms appeared relatively recently and the purpose of this study was to compare domestic normative methods of calculation with non-significant ones. During the presentation of the study, the concept of a reduced (effective) section of a beam when working on bending was considered. Also, the same stages of the calculation methods were noted, indicating the places where the methods differ in their opinions. The result of this study is a comparison table for the basic geometric characteristic for obtaining the bearing capacity of an effective torque element of resistance. An analysis was carried out and a conclusion was drawn on these values.
Keywords: steel structures, light steel thin-walled structures, thin-walled beams, reduced cross-section, bending work, C-shaped profile, effective cross-section, effective area, effective resistance moment
In this paper, it is proposed to update the values of the bearing capacity of the hinge attachment of the beams to the columns on 2 bolts. A comparative analysis of the bearing capacity of the assembly presented in the 2.440-2 release 1 series and calculated according to modern building codes is carried out. Five calculation formulas were obtained for the five possible limiting states of the node. A table with the values of the limiting forces perceived by the connection is presented. A possible variant of improving the assembly is presented, by including a support table in the work.
Keywords: bearing capacity, metal structures, hinged unit, structural solution, connection of elements, limit state
The article deals with the stages, causes of origin and actual problems of high-rise construction in Rostov-on-Don. Examples of successful development of high-rise buildings in Russia and abroad are given. The problematic aspects are analyzed, possible ways of solving on the basis of the experience of other cities in the construction of unique buildings are shown.
Keywords: high-rise construction, town-planning, skyscraper, design, architecture, number of storeys, Rostov-on-Don, development, zoning, world practice, normative and legal documentation
the design of a new object presupposes not only the functional aspect, but an important factor is the location of the building or structure. The choice of location is one of the fundamental criteria: it is necessary to take into account the infrastructure and architectural appearance of the selected area, the needs of the district or region in the projected facility.
Keywords: constructivism, the architectural appearance, the blue line, multi-center, prototype, monuments, cultural centers, the Great Patriotic war
The results of a computational experiment performed in the Lira-SAPR environment are considered in the article. The purpose of the experiment is modal analysis of various structural schemes of multi-storey reinforced concrete frame under pulsating and seismic influences. The considered design schemes differ in the ratio of the frame and diaphragm components of the frame. It was calculated three series of samples, differing by the ratio of rigidity. The stiffness ratio varied from 20% to 65.9%. Within each series calculations were performed for seismicity of 7, 8 and 9 points. For each variant of seismicity, the soils of the 1st, 2nd and 3rd seismicity categories were considered. It is established that when the role of the frame part increases, the distribution of the modal masses shifts towards the lower forms of oscillations, and the numerical values of their frequencies decrease. Accelerations of the nodes of the coating from the ratio of rigidity do not depend. They increase with increasing seismicity of the site. The ratio of stiffness affects the total consumption of the reinforcement of slabs. This influence is significant in the range of values of the ratio from 20.5% to 42.5%. Further increase in the ratio of stiffness to the consumption of reinforcement influences slightly.
Keywords: seismicity, category of soils by seismic properties, modal analysis, rigidity, selection of fittings, PC Lira-SAPR
The purpose of this article is to identify shortcomings in the construction of prefabricated buildings and structures on the basis of an analysis of a number of scientific publications of domestic and foreign scientists. Since not only buildings, but also structures can be prefabricated, it is proposed to use the term "fast erectable building systems" (BSS). It is noted that, despite the great advantages of the FSU, at the current stage of development they do not fully meet the requirements of reliability, energy efficiency, rationality and comfort, suitability for operation under any climatic conditions.
Keywords: prefabricated building, view, technology, field of application, dignity, defect
Article is devoted to studying of a possibility of realization of the principles of probability projection of structural production on the example of technological operation of the device of reinforced concrete walls and partitions.
Keywords: construction, model operation, probability projection, reliability
The article describes the relevance of the design of tall buildings. A characteristic feature of high-rise buildings is preferential perception of horizontal loads under the impact of the wind flow. Therefore, the stiffness stems represent the most characteristic for high-rise construction internal vertical support structure.
Keywords: high-rise building, strength, reliability, a horizontal load, the core stiffness, trunk stiffness, the layout structure, column, frame, diaphragm stiffness
The article is devoted to the problem of determining the air flow through cracks in the enclosing structures using numerical methods. Based on the study of the data obtained during the visual inspection, it was found that most of the apartment buildings have significant physical wear, which is mainly characterized by the presence of cracks. Particular attention is paid to the assumptions made for the design scheme. On the basis of the equations of dynamics and continuity, a mathematical model is obtained that allows one to predict the airflow through the crack
Keywords: physical wear, air mass flow rate, crack, permeation, water steam, heat and mass transfer, controlled environment, visual examination, air change, air permeance, numerical methods
Using simulation and finite element method calculations of stress-strain state of monolithic concrete support for underground structures with non-circular outlines made of fast-hardening concrete are carried out in the paper. Based on the obtained results, the maximum stress zones and their magnitude in the reinforced concrete support are established. The stresses are compared with circular-form supports. The factors influencing the stress state of the support are determined.
Keywords: Underground structures; soils; concrete support; voltage; the experiment plan; modeling; finite element method
The paper provides summary the problems of estimating high-rise buildings to a progressive collapse. The analysis of the structure of the technique for calculating the skeleton of the building for a progressive collapse is performed. Recommendations are given on the properties of reinforced concrete carcass elements for emergency actions. An imitation simulation of the emergency response using the finite element method in calculating the building frame for progressive collapse was proposed; Modeling and investigation of the stress-strain state of individual elements of the building's frame for the effect of explosive loading; modeling and investigation of resistance to the progressive collapse of the skeleton of a high-rise building; development of constructive solutions to achieve resistance to progressive collapse.
Keywords: progressive collapse, special action, finite element method, building frame modeling, stress-strain state
The article considers the main ways to increase the energy efficiency of the designed buildings, taking into account the natural, climatic and spatial conditions of the territory, as well as methods for increasing energy efficiency using energy-saving materials and equipment, and applying the corresponding spatial, architectural, planning and constructive solutions.
Keywords: Energy saving, heat supply, energy efficiency, environment, territorial development, wind impact, insolation, alternative energy sources
The article gives judgments, focuses on the need for the development of military and town-planning sciences, based on the reality of practice, which, apart from armament, must take into account the urban and architectural components formed as a special kind of weapon of future wars.
Keywords: Urban planning, Armed forces, military science, architecture, defense infrastructure, housing
Abstract: preventing the formation of ice on roofs and gutters of buildings appears to be socially and economically significant goal, requiring efficient and effective decision-making. Roof and gutters heating has the potential to avert the loss of life and vehicles damage due to falling icicles. The costly package of measures of manual cleaning of roofs, which often leads to unscheduled repairs of roof , gutters and facades of buildings is thus not needed. A competent choice of the way of heating is able to provide positive social and economic benefits for the city and must be done according to the availability of specific types of energy resources ... The article justifies the applicability of water heating system that runs in both automatic and manual control. Such systems allow the use of heat supplied by CHP local boiler or gas compact heater.
Keywords: Key words: energy-saving technologies, water heating systems, convective heat transfer, heat transfer EFFICIENCY, electronic control unit, ecological efficiency, dependability, vandal resistance, social and economic effects