It is shown that the given ratio of the modulus of deformation and the initial modulus of elasticity of concrete depends not only on the type of the function ε = f(𝜎), and from the initial modulus of elasticity of the concrete, i.e. concrete with different values of initial modulus at equal strength, for example, with the introduction of the composition of concrete organo-mineral modifiers, the dependence of the ratio E𝜎/E0 from the loading level will vary. To describe the "stress-strain" or "modulus of deformation-level of loading" for concretes with organo-mineral modifiers, it is advisable to use The sargin diagram, taking into account the influence of modifiers on the main deformation constants: the initial modulus of elasticity, the coefficient of elasticity, the relative deformation corresponding to the short-term strength limit. The nature of deformation of concretes with organo-mineral modifiers at a loading level above 0.9 may differ from the known patterns for traditional concretes, in connection with which this issue requires special study.
Keywords: modulus of deformation, stress-strain diagram, modified concretes, loading level, modulus of elasticity
The article deals with the existing problems in our country, arising in the management of material resources in the process of construction of buildings and structures. The main problem in the material resources management system is that due to their late and incomplete delivery to the construction projects, there are significant downtime of working and construction machines and mechanisms. The don state technical University (DSTU) is developing an intelligent construction management system, which includes a method of planning and accounting for the movement of material resources to ensure synchronization of the processes of construction and installation works and their complete supply. The use of this technique allows to optimize the timing and volumes of supplies of material resources in accordance with a given technology of production operations and the simultaneous control of their inventory in the onsite warehouse
Keywords: organization of construction; economy of construction, production of building materials
The analysis of the existing management systems for investment and construction projects showed that the organizational and technological models used for the development of the calendar plans are static and do not reflect changes in the course of real-time work that does not allow synchronizing the terms of production and supply of resources and leads to significant losses in use of manpower and construction machinery. The adaptability of organizational and technological models in the developed intellectual building management system is ensured through the use of special algorithms and models for disaggregating planned and aggregating actual information on work, calculating deviations of actual characteristics from planned values, developing and making decisions to bring the model to the organizational and technological normality in real time mode
Keywords: management of investment and construction projects, organizational and technological models, adaptive systems, intelligent management systems, operational management of the construction site, pace of work
The article deals with the problems existing in our country that arise in the construction of buildings and structures using new materials and engineering technologies. As shown by the analysis, one of the most significant problems in this area is the violation of production technologies using new materials. To overcome this situation, it is proposed to set the technological normal at the design stage by developing technological maps that take into account the composition and sequence of operations taking into account the properties of energy-efficient materials in detail. In Donskoy State Technical University (DGTU) is developing an intelligent management system that provides organizational and technological and information integration of the stages of design and production through the creation of a single database of technological maps, volumes of work and resources
Keywords: integration, database, the resource classifier, engineering, life cycle of construction products
This article deals with the field of application of fiber-reinforced concrete, reveals the advantage of using fiber-reinforced concrete in comparison with conventional concrete. The efficiency analysis of the use of fiber-reinforced concrete is analyzed.
Keywords: fiber concrete, concrete, reinforced concrete, structures, technologies, installation, fiberglass concrete, reinforced concrete structures, tension, prestress, basalt fiber concrete
This article deals with the introduction of reinforced concrete structures with a variable pre-stress combined along the span. The identification of economic efficiency from replacement of reinforcement and prestressing is carried out.
Keywords: concrete, reinforced concrete, structures, technologies, installation, reinforced concrete structures, tension, prestress, beams, reinforcement, efficiency
The most promising technologies of concrete and reinforced concrete for the underground construction and transport. The studies with the inclusion of concrete and steel and polypropylene fibers. The factors affecting the strength and modulus of deformation materials. The conclusion about the need to study the effectiveness of the concrete with a combined reinforcement.
Keywords: Concrete and underground construction, fiber, strength, modulus of deformation
Management can be performed on the principles of motivation, planning, regulation of the course of production, coordination, organization and control on execution of decisions. Operate and develop the production units, depending on the goals
Keywords: structure, management, goal, head, processes, organisation.
This article is devoted to the consideration of economic, social and urban effect in the co-production work on the laying of utilities. The main results of evaluation of the economic efficiency of the options considered gasket types of utilities.
Keywords: efficiency, design, evaluation, variance, network engineering, installation
In article the direct connection of a condition of soils and quality of a formed superficial diffusion drain is considered. For minimization of pollution of a superficial drain and ground waters when unloading them in a reservoir it is offered to use coal mining waste as a sorbent of organic and inorganic pollution. Thus, the area of utilization of dump breeds of coal mines for nature protection and soil-improving actions extends.
Keywords: Dump breeds of coal mines; sorbent; minimization of pollution of a superficial drain; the urbanized territories; anthropogenous impact on the soil
This paper presents a comparative analysis of the effectiveness of the method Cuthill-McKee algorithm and fill-reducing ordering of a sparse matrix, based on multi-level nested dissection paradigm, developed at the Department of "Computer Science and Engineering," University of Minnesota. For short, we shall call the algorithm Cuthill-McKee CM, and the algorithm of the University of Minnesota — NodeND (Node nested dissection). This article uses a modification of the CM algorithm — RCM (reverse Cuthill-McKee), because in practice the reverse numbering index allows you to get a greater advantage than using a direct algorithm CM. The reason for using these algorithms are high speed computational algorithm, as it is necessary to solve the system proximal to the diagonal, the great acceleration of algorithms for solving FE problems using technology such as CUDA
Keywords: finite element mesh renumbering methods, three-dimensional mathematical modeling, elasticity theory problems, finite element method, finite element meshes
The article presents a brief overview of the results of a study of the compressed elements in our country and abroad, reinforced composite materials. Noted that in Russia this question is poorly understood. Represented a broad research program developed by the Department JBK RSSU aimed to fill these questions.
Keywords: concrete, steel, carbon-fiber reinforcement, test samples, strength, deformability, cracking.
On the basis of experimental data on the resistance of reinforced concrete columns eccentric compression was obtained analytical dependence of the limiting compressibility of concrete from the varied factors: the relative eccentricity of the external force eo / h and the reinforcement ratio μ.
Keywords: reinforced concrete column, longitudinal reinforcement, a protective layer of concrete, finite element method, critical load
The article is devoted to the scientific basis for the concept of safe principles of sustainable development in the process of urban planning and selection of investment and construction projects of development of urban territories. The author on the basis of the analysis of legislation and normative and legal basis discussed approaches to the characterization of the safe development of the urban environment, studied the principles of sustainable development-based approach to the application of the concept of acceptable and reasonable risk in the planning of urban development of urban territories, identifies areas and the boundaries of their realization.
Keywords: concept of security, urban planning, integrated development, urban territories, the risk of
This paper addresses the testing results of steel rods with grade A500 and A600, which used as a conventional reinforcement. It was investigated the strength properties of carbon and fiberglass sheets with different number of material layers. The results are compared with the data given in the quality certificates.
Keywords: fiberglass, carbon frp sheets, laminates, sheets of carbon and fiberglass, the ultimate load ,strength