The problems of competitiveness of construction organizations and ways to solve them investigated. The factors limiting the business activity of construction organizations are highlighted and evaluated based on statistical data. Three main categories and corresponding specific factors of competitiveness of construction organizations analyzed. The method of expert assessments revealed the degree of their influence on the competitiveness of the organization. The ways of increasing the competitiveness of construction organizations, taking into account these factors, proposed.
Keywords: competitiveness, increasing competitiveness, factors of influence, construction organization, statistical methods, the method of expert assessments
the effect of a thickener and a setting retarder on the technological properties of GSHS START is investigated. One-factor plans of a two-factor model have been developed, with a minimum (0.1%; 0.005%) and maximum (0.2%; 0.05%) dosage levels of pore-forming and water-retaining additives, respectively. Regression equations of output parameters in the form of a second-degree polynomial are obtained using regression and correlation analysis of experimental data. The values of partial correlation coefficients are analyzed. With an increase in the dose of water-retaining and pore-forming additives from 0.1% to 0.2% and from 0.005% to 0.05% of the binder, respectively, for all possible combinations of the dosage of the thickener and setting retarder, there is an increase in setting time by 10 ... 72%, and sliding by 33 ... 80%. The least sensitive to an increase in water-retaining and pore-forming additives was a mixture in which the amount of thickener is 0.2% (at the upper level), and the amount of moderator is 0.04% (at the lower level).
Keywords: technological properties, organizational and technological solutions, dry building mixes, functional additives, thickener, setting, retarder, two-factor experiment, coefficient of determination, regression analysis, correlation analysis
The properties of fiber-vermiculite concrete composite are investigated. Analysis of the results showed that reinforcement with basalt fibers of the matrix increases the flame retardant properties. The presence of basalt fibers in the composite significantly increases the strength and flame retardant properties of the initial matrix and reduces the thickness of the flame retardant layer. The highest values of bending strength are achieved with a 0.9% reinforcement percentage and a ratio of fiber length to diameter equal to 1444.
Keywords: composite, basalt fiber, reinforcement, vermiculite concrete, dispersed, strength, bending, flame retardant properties, compression, matrix, thickness, percentage of reinforcement
The article deals with the actual problem of minimizing the negative impact on the environment of the construction process. The concept of sustainability in the construction industry is defined. The main factors contributing to the formation of sustainability in the construction industry are identified. Practical recommendations for solving environmental problems in the construction industry have been developed.
Keywords: sustainability, construction, ecology, energy conservation, sustainable materials, resource conservation, efficiency, ecological balance
Operational characteristics of reinforced concrete bending elements under low-cycle impact are considered. The residual deformations and deflections of partially prestressed structures exposed to repeated static loads are investigated, the dependences for estimating the residual deformations and deflections of partially prestressed structures under the action of low-cycle loads are Given. On the basis of the analysis, the dependence of the relative increase in deflections on the coefficient of partial prestressing with repeated application of static loads was established.
Keywords: partially prestressed elements, repeated loads, residual deformations, non-stressed reinforcement, low-cycle impact, residual deformations and deflections
The article considers the urgent problem of minimizing the negative environmental impact of the construction process. The values of maximum and gross emissions into the environment during the construction of the facility are calculated, a set of measures is proposed that reduce the level of negative environmental impact during the implementation of the construction project. Practical recommendations on the organization of construction production taking into account environmental indicators have been developed.
Keywords: ecology, assessment, environmental impact, optimization, construction production, monitoring, measures to reduce emissions
investigated the concept of competition and competitiveness of construction organizations. Analyzed the main and specific factors of competitiveness of construction organizations. The ways to improve the competitiveness of construction organizations, taking into account the main and specific factors, are proposed.
Keywords: competition, competitiveness, competitiveness improvement, competitiveness factors, construction organization
The article shows that when solving the problem of optimization of the project of construction works it is necessary to take into account the factors of energy and resource saving. An assessment of the importance of the criteria for energy and resource saving measures at the design stage of the construction organization project is given. The use of matrices of paired comparisons allows you to perform the optimal search for energy-saving measures, which will lead to the selection of effective organizational and technological solutions at the stage of development of the project of works.
Keywords: project of construction works, optimization, resource saving, energy saving measures, matrix of paired comparisons, ranking, vector of priorities
The deformation model is considered in relation to the bending elements most characteristic of partially prestressed reinforced concrete structures. The bearing capacity and deformability of partially prestressed structures are investigated. Given the criteria of strength of compressed concrete that meets the attainment of the ultimate strain in the compressed concrete, as well as stretched in the longitudinal reinforcement, characterized by the achievement of the ultimate strain either in stressed or non-stressed reinforcement. The analysis of the calculation results of the strength and deformability of partially prestressed structures under short-term and long-term effects of the load on the deformation model and the norms. It is shown that the deformation model accurately estimates partially prestressed reinforced concrete elements with different types of loading for any combination of tensioned and non-tensioned reinforcement by strength and deformation.
Keywords: partially prestressed elements, deformability, strength, non-stressed reinforcement, state diagrams, deformation model
Studied the technical condition of the housing Fund of the Republic and its energy saving potential. The analysis of the impact of energy saving measures on the thermal parameters of residential buildings. Shows a practical illustration of the economic effect from implementation of energy saving technologies.
Keywords: housing, energy conservation, energy upgrading, energy saving technologies, economic efficiency, optimization
The structure and content of the energy renovation of the housing stock. Algorithms of calculation of economic efficiency of energy saving measures. The analysis of the impact of energy saving measures on thermal parameters of residential buildings. The practical illustration of the economic effect from implementation of energy saving technologies in the process of complex modernization of the housing stock.
Keywords: housing, energy conservation, energy modernization, energy-saving measures, economic efficiency, overhaul, optimization
A new approach to solving the problem of evaluation of strength of concrete in torsion. The basic idea of this theory is that the torsion causes the bending element in a plane 45 ° angle. Solved the problem of assessing the strength of rod reinforced concrete elements in torsion. Development of methods of calculation of durability of reinforced concrete elements in torsion has allowed to pass to the decision of problems of strength under twist with torsion.
Keywords: Research, reinforcement, strength, crack, twist, torsion, reinforced concrete, element, hole, beam
Analyzed the structure and content of the comprehensive modernization of the housing stock. The mathematical model of optimization of complex processes of modernization of the housing stock. Given the approach to the distribution of funds between departments so that, in General, minimized the magnitude of the complex physical deterioration of buildings.
Keywords: comprehensive modernization, dynamic programming, repair, housing, optimization
The structure and maintenance of housing analyzed. Put more abstract and an extensive understanding of the concept of modernization as the complex development of residential real estate. Given multiobjective mathematical model of optimization of complex process of modernization with the required adequacy.
Keywords: comprehensive modernization, reproduction, reconstruction, sanation, housing fund, optimization
The structure and maintenance of housing analyzed. Put more abstract and an extensive understanding of the concept of modernization as the complex development of residential real estate. Classification of modernization of housing types: endogenous, endogenously-exogenous, and exogenous to create a multi-objective optimization model of the process with the required level of adequacy. Theoretical substantiation of complex approach.
Keywords: modernization, endogenous modernization, endogenously is the exogenous modernization, exogenous modernization, reproduction, reconstruction, housing, housing management