The article discusses a methodology for improving the energy efficiency of historical buildings that have objects of protection. The main ways of energy saving, which are revealed at the level of the microclimate of the premises, are also considered. The relevance of the topic is due to the complexity of performing work to improve energy efficiency if it is necessary to preserve the historical value of cultural heritage sites. The article proposes organizational and technological measures that allow optimizing costs by reducing losses of thermal energy, by modernizing heating, ventilation and air conditioning systems in the conditions of the historical development of the city of St. Petersburg.

Keywords: energy efficiency, construction organization, engineering systems, restoration work, historical buildings

The article compares the technologies of methods of building construction in a short time, shows the advantages and disadvantages. A summary table of comparative characteristics of building construction technologies has been formed, the terms of construction of one floor for each method and the limitations of its application have been determined.

Keywords: method of lifting floors and floors, construction technology, monolithic, large-block, frame, volumetric-modular, contour, advantages, disadvantages

The article is devoted to solving the problems of choosing a variant of the calendar plan in the complex development of residential microdistricts. At present, a methodology for linking construction and installation works in time and space is being developed, new methods for calculating the organization of work are emerging. Due to the constant change in regulatory requirements in construction, the essential characteristics of scheduling methods change. Variant analysis may include a sufficiently large number of indicators of the quality of the organization of complex development. Therefore, a method for comparing options and choosing the best one is proposed, which takes into account an unlimited number of indicators of the quality of work organization.  At the same time, different indicators can be taken into account for different regions, as well as new ones can be added. The effectiveness of the methodology is analyzed on the example of a residential area.

Keywords: residential area, variant analysis, flow organization of work, quality indicators, regulatory requirements

The purpose of this work is to develop a list of possible categories of the need for major repairs and appropriate criteria for evaluating structural elements and in-house engineering systems. In the process of working on this study, methods of statistical data collection and expert evaluation were applied. As a result of this study, a table of the Category of the need for major repairs of apartment buildings, Criteria for assessing the need for major repairs of apartment buildings, was also presented by the algorithm of actions of a specialist in determining the need for major repairs of apartment buildings. This work is an effective and relevant method for determining the need for major repairs of apartment buildings in comparison with VSN 53-86(p) "Rules for assessing the physical wear of residential buildings".

Keywords: major repairs, apartment building, expert evaluation method, operational reliability, category, criterion

The article aims to reveal the essence of the application of multi-criteria decision-making methods in relation to the process of organizing construction production. An overview of multi-criteria decision-making methods is presented. The criteria for the optimal choice of the calendar plan as the main document in the design and implementation of the construction process are described. Using the example of the initial construction schedule, alternative options are proposed and calculation is carried out using multi-criteria decision-making methods to select the best one based on the specified criteria and the situation

Keywords: multi-criteria decision-making methods, calendar plan, construction process, construction organization.

In the modern world, the issue of the importance of energy conservation and energy efficiency improvement in various areas, including the housing and communal sector, is quite acute. The use of modern energy-efficient materials and technologies in residential buildings, including during the overhaul of residential buildings, makes it possible to reduce energy consumption and save significant funds for citizens on utility bills.

Keywords: energy intensity, energy efficient technologies, energy saving, housing and communal services, overhaul

The authors of the article have developed an economic and mathematical model for determining the influence of factors characterizing the specifics of dismantling works on the operating costs and duration of operation of machines and mechanisms, the scientific novelty of which is that, unlike existing models, it takes into account the normative-parametric method, regression and covariance dependencies, which makes it possible to assess the totality of the influence of factors on operational costs and duration of operation of machines and mechanisms, describe the procedure for calculating the operating costs and duration of operation of machines and mechanisms and generate the amount of investment in the operating costs of machines and mechanisms.

Keywords: dismantling works, economic and mathematical model, operating costs, machines and mechanisms

This article described in detail the visualization of 5 case studies in Iraq with two important subjects; The first subject is construction quality control using BIM-compliant construction projects employing Autodesk Revit software; The second subject is quality assurance using BIM and energy analysis, which evaluates the energy usage in accordance with BIM utilizing Autodesk Revit software, and Autodesk Green Building Studio(GBS) Cloud. There are several causes that lead to the selection of these case studies. These case studies are applied models or examples executed by many Ministries such models exist in other governorates in Iraq. Despite the fact that the research topic of quality improvement utilizing Building Information Modeling (BIM) technology was not used in the chosen models, these buildings had several challenges throughout the execution phase. This research will be more valuable when implementing government agencies and private sector companies specialized in construction. wants to use BIM technology to improve the execution quality for future buildings.

Keywords: energy analysis of buildings, construction project, Building Information Modeling, quality, quality control, quality assurance

The subject of the study is processes related to the construction of strip-shell foundations. The scope of the study is the construction of the base under the shell, providing a curvilinear contour of the structure. Traditionally, the foundation structure is placed in undisturbed soil, which, due to its physical and mechanical characteristics, can limit the scope of application of such foundations. Using the Harrington desirability function, the authors evaluated six models of soil masses with different physical and mechanical as well as technological properties. As a result of the studies, the suggested options were rated “satisfactory” or lower. In this regard, it is required to improve both the quality of the base under the shell and the technology for the construction of such foundations by using cost-efficient prefabricated soil-cement blocks.

Keywords: Buildings, strength, construction industry, foundation, construction technology

The article deals with the issues of assessing the effectiveness of the construction and operation of metal corrugated pipes. The characteristic features and difficulties of the operation of corrugated metal culverts in areas of permafrost distribution are revealed. The characteristics of the main defects of culverts are systematized. The features of thermophysical calculations of metal corrugated pipes on a frozen base are analyzed in detail. Recommendations are given on the application of the most effective technical solutions in the construction of corrugated metal culverts on permafrost soils.

Keywords: highway, culverts, metal corrugated pipes, thermal conductivity, permafrost soils

As part of the development of the stages of pre-project and design preparation, a set of procedures is carried out, starting with planning further stages of the implementation of a construction project, ending with obtaining a construction permit. The article describes the main provisions of the methodology for choosing rational organizational and technological solutions at the stages of pre-project and design preparation of an object for construction, and also presents the results of its implementation in construction practice. The methodology defines the main procedures at the stages of pre-project and design preparation of facilities for construction; factors influencing the duration of the procedures at the stages of pre-project and design preparation of facilities for construction. On the basis of the methodology for choosing rational organizational and technological solutions at the stages of pre-project and design preparation for the construction of an object, organizational and managerial models for passing the stages with determining the duration of procedures, taking into account the influence of factors, have been developed. The proposed methodology, used in the practice of the organization, made it possible to take into account the influence of factors on the duration of the stages of pre-design and design preparation of the above facilities for construction, thereby reducing it.

Keywords: technical customer, developer, stages of pre-design and design preparation of facilities for construction, organizational and technological solutions

In the article, it is proposed to take the density of soil particles as the maximum density, the determination of which does not require sophisticated equipment, is determined in the laboratory using a pycnometer, while the density of soil particles is a fairly stable value, depending only on the composition of the soil. As a result, a more advanced method has been developed for assessing the degree of compaction of sandy soils by using the density of soil particles and statistical dependencies as the maximum soil density without directly determining the maximum density and optimal soil moisture in the laboratory according to GOST 22733-2016. Based on the research of BeldorNIA, it is proposed to take the density of soil particles as the maximum density, the determination of which does not require the presence of complex equipment.

Keywords: highway, soil, soil compaction, soil composition, road surface, road defects, trackage, road construction, method, pycnometer

The technology of organizing the construction of decentralized energy systems based on wind power plants is given. New design solutions for the structural elements of wind turbines and overhead lines (tower, collapsible ballast-type foundation, protective element) are proposed, taking into account the specifics of the technology of construction and installation works. Data are given on reducing the cost of construction production by optimizing the machines and mechanisms used.

Keywords: wind turbine structures, overhead lines, tower, collapsible ballast-type foundation, protective element, in-line method, decentralized system

The purpose of the study was to find methods to reduce the construction time of special purpose structures. The analysis of the factors influencing the terms of construction of nuclear power plants is carried out. Using the example of calculating the parameters of the ventilation pipe installation of a really erected nuclear power plant, the advantages of replacing the traditionally used for the construction of these structures with the method of "falling arrows" are noted.

Keywords: falling boom, set of machines, installation of structures, scope of work, traction mechanisms, continuity of work, cost, construction period, commissioning period, work cycle

A feature of modern construction is the large-scale reconstruction of blocks in the center of large cities. In recent decades, investors have increasingly sought to increase the number of storeys of buildings. However, the construction of high-rise buildings (above 75 m) in the conditions of the current development of the metropolis has a number of problems that can negate all the benefits of placing a real estate object in the central districts of the city. The greatest problems are identified already at the design stage of the foundations of high-rise buildings. The article discusses 5 key problems that have the maximum impact on the increase in the cost of construction of high-rise buildings.

Keywords: high-rise buildings, the conditions of the existing development of the metropolis, engineering and geological surveys, dense urban development, geotechnical forecast, geotechnical monitoring, excavation, pile foundations

The introduction of construction work in urban development is associated with a number of important factors, as well as near unusual engineering and geological conditions. In this regard, design schemes were identified for the construction of new buildings erected in cramped urban areas. Thus, it was found that the most suitable structural scheme for various buildings is a frame with the implementation of certain structural changes in view of the cramped conditions. This also applies to the design scheme of the foundations. This paper discusses the main structural schemes, as well as schemes and their design changes to ensure the reliability of a public building being built in cramped conditions.

Keywords: structural scheme, cramped conditions, urban development, public buildings, construction objects, architecture, building system, compacted buildings, organization of work

The poor performance of the construction of buildings has been the subject of discussion over the past century, and hence, substantial initiatives have been taken to address the poor management. The article aims to evaluate the reality of execution quality in engineering projects in Iraq in the public and private sectors. For this purpose, a questionnaire was designed commensurate with this purpose , and the questionnaire was distributed to engineers and technicians in the public and private sectors. For the data analysis and computation of percentages, mean, and standard deviation for each response, statistical software (SPSS-V28) was utilized. As a consequence of the answer analysis, the results determined that there is a deficiency in the execution quality, project management's obligations to assure and regulate quality, and non-compliance. Also results shown there is a need to use modern and advanced Building Information Modeling programs to ensure and control quality that is characterized by accuracy and clarity, as well as to provide an integrated system to which project parties can return when needed .The current software is used to control execution quality.

Keywords: construction project , Building Information Modeling , quality, quality control, quality assurance.

The method of fixing soils is injection filling of voids, which is produced by binding materials - cements, clays, bitumen, etc., and sand, sawdust, loam, suspensions are used as inert fillers. It is possible to improve the quality of cement composite solutions through the use of reinforcing additives, which in the future will ensure a high degree of reliability, safe operation of facilities. The paper considers the possibility of involving nano-additives in grouting compositions, such as aluminosilicates, in particular boehmite. Studies of the hardening processes of composite solutions in the presence of bentonite grade P1T1 with different content of boehmite have been carried out. The concentration of boehmite at which the rate of hardening of the composite solution is maximal is determined. In order to save cement, the effect of the surfactant on the strength of the composite solution was investigated, it was found that the 20% introduction of the surfactant into the composite solution gives a strength that almost coincides with the zero sample.

Keywords: safe operation, plugging compositions, boehmite, surfactants, strength, structure formation, optimal concentration, nanosystem, modifier, cement

The main content of the diversification of production as the activity of business entities is considered. manifested in the purchase of existing enterprises, organizations of new enterprises, this article proposes a method of using GIS to optimize the sewage system of critical areas. The nearby territory of the Volgograd Arena stadium was chosen as the site of work.

Keywords: ArcGIS, Storm and Sanitary Analysis, Civil 3D, Sewage.

In view of the trend of transition to the Western experience of construction, which implies the delivery of objects with a complete set of finishing works, developers and investors have a need to involve the technical customer service to carry out construction control, at the stage of finishing works. Since a clear system of controlled indicators has not been established to improve the quality of finishing works, this article is devoted to the identification of the main cycles of finishing works and the typification of the most common defects, with a reserve for the establishment of factors that affect the manifestation of these defects in the production of finishing works.

Keywords: finishing works, quality control, technical customer service, type of finishing works, complex of technological processes, defect, cycle

The article considers the assessment of the construction of social facilities in the development of territories of integrated development on the example of Rostov-on-Don. As part of this, the analysis of the territorial needs of the city of Rostov-on-Don in the construction of social institutions, spatial analysis of the placement of territories of complex development was carried out. A project for the construction of a preschool institution using green technologies has been developed and the effect of the results of the construction of the projected preschool institution has been calculated.

Keywords: сonstruction, preschool, integrated development, territory, project, urban environment

The buildings of the old housing stock, dating back to the second half of the 19th century, were built of bricks with lime mortar, the foundations were made of rubble stone, with and without cellars, the roofs were made of metal tin sheets on wooden rafters. Interfloor and attic floors were arranged on wooden (mainly pine wood) or metal beams with wooden filling. The building materials used for the construction of buildings of that period differed in strength characteristics, service life and, at the same time, were subjected to various negative influences during the period of operation. During the reconstruction of the ceiling on wooden beams, the standard service life of which is 40-60 years, it is necessary to install new ceilings, while preventing the destruction of the brickwork of the walls and the performance of work in difficult cramped conditions.

Keywords: reconstruction, housing stock, floors, inspection, defects, wooden beam, metal beam, profiled sheet

The technology of erecting inverted green roof in exploited roofs is becoming increasingly relevant in modern construction in accordance with the principles of sustainable development and energy efficiency. However, the theoretical support for the design and construction of an inverted roof is still not enough – there is no comprehensive analysis of the roof structure, which would comprehensively take into account various criteria. The study developed mathematical models of three systematized groups of erection of inverted roofs (on supports, without supports and roof-parking) according to three enlarged criteria that comprehensively characterize their design: tecnological efficiency, resource efficiency and environmental friendliness. The results of the study make it possible to determine the optimal solutions for roofing at the stage of variant structural and technological design for their further improvement and application in construction practice.

Keywords: inverted roof, exploited coating, system of criteria, systematization, structural and technological design, variant design, expert analysis, mathematical modeling, technological efficiency, efficiency, environmental friendliness

The optimization of the taxable base of capital construction objects is considered, this is the desire of customers and operating organizations to manage the cost of ownership of one or another technical solution, which is certainly reasonable in modern conditions, when when making a technical solution, its full cost is estimated, including the so-called cost of ownership for the entire period of the life cycle of the object, from the formation of an idea for the creation of a future object to its decommissioning.

Keywords: collapsible foundation, protective element, flow method, wind power plant, building structures

When designing engineering structures, the efficiency of the engineer’s work is important. The cooperation between individual programs in BIM technology is very important in this aspect, because it significantly speeds up the work and, as a result, the design process is less time-consuming. In the process of designing steel structures, the first stage is the selection of an appropriate structural solution, then numerical calculations of the model together with all assigned load cases and dimensioning of individual elements of the structure in terms of the ultimate and serviceability limit state. After selecting the appropriate sections, you can start working on the detailed drawings of a given structure. When performing numerical calculations and drawings, at least two programs should be used. The article presents the cooperation between the Dlubal RFEM numerical calculation program and the Tekla Structures building structure modeling program on the example of a steel structure floor design.

Keywords: BIM, Dlubal RFEM, Tekla Structures, steel structures, direct import, engineering structures