University of real actions
Pages 5-6
DOI: 10.22227/1997-0935.2016.1.5-6
Articles count - 17
Pages - 191
Pages 5-6
DOI: 10.22227/1997-0935.2016.1.5-6
Pages 7-21
ON THE EXAMPLE OF KUZBASS The contemporary urban planning problems are of multifaceted character and are directly relevant to fundamental aspects of the development of the society - social sphere, economy, land and property relations, material environment and its safety, preservation of historical and cultural heritage, ecology. In spacial planning aspect urban planning is, first of all, planning and design, including scientifically justified legal regulation, spatial organization of territorial objects (of a country and its regions, settlements, components of planning structure: planning centers, axes, zones, etc., separate land plots), i.d. forecast of their future state - use, development or reconstruction. All these should be included into town planning documentation. The author specified the range of problematic urban planning issues, which refer to urban border areas. The methods, mechanisms and measures to define urban border areas including several interdependent urban and rural settlements situated in different city regions are offered using the example of Kuzbass. The backgrounds for the creation of BIM system for planning, design, construction and further management and operation of infrastructure objects are created within the formed urban border areas of coal mining.
DOI: 10.22227/1997-0935.2016.1.7-21
Pages 22-34
ASPECTS All over the world a lot of unique architectural monuments are lost according to different reasons. The role of cultural objects can hardly be overestimated and their total loss is irretrievable. Preservation of architectural monuments and complexity of their investigation and design solutions development depend on many factors: age of the monument, structural peculiarities, geographical position, their value as objects of cultural heritage, etc. The article offers the description of a reconstruction project of a bell tower in Joseph of Volokolamsk Monastery, which had been destructed in 1941. The bell tower in Joseph of Volokolamsk Monastery situated in Volokolamsk region of the Moscow Region near village Teryaevo is an outstanding example of the architecture and construction technologies of the 16th-17th centuries. The design group conducted extensive research, made a conclusion on the state of the surviving elements and offered several variants of bell tower reconstruction. It was decided to reconstruct the bell tower over the surviving first tier with transferring the loads to the new bearing structure. The first tier is being reconstructed and preserved.
DOI: 10.22227/1997-0935.2016.1.22-34
Pages 35-43
Concrete arches are widely used in the construction of underground facilities. The analysis of their work under dynamic loads (blasting, shock, seismic) will improve the efficiency of design and application. The article addresses the problems of calculation of reinforced concrete arches in the ground in terms of the action of dynamic load - compression wave. The calculation is made basing on the decision of a closed system of equations that allows performing the calculation of elastic-plastic curved concrete structures under dynamic loads. Keeping in mind the properties of elastic-plastic reinforcement and concrete in the process of design variations, σ-ε diagrams are variable. The calculation is performed by the direct solution of differential equations in partial derivatives. The result is based on a system of ordinary differential equations of the second order (expressing the transverse and longitudinal oscillations of the structure) and the system of algebraic equations (continuity condition of deformation). The computer program calculated three-hinged reinforced concrete arches. The structural calculations were produced by selection of the load based on the criteria of reaching the first limit state: ultimate strain of compressed concrete; ultimate strain tensile reinforcement; the ultimate deformation of the structure. The authors defined all the characteristics of the stress-strain state of the structure. The presented graphs show the change of bending moment and shear force in time for the most loaded section of the arch, the dependence of stresses and strains in concrete and reinforcement, stress changes in time for the cross-sectional height. The peculiarity of the problem is that the action of the load provokes the related dynamic forces - bending moment and longitudinal force. The calculations allowed estimating the carrying capacity of the structure using the criteria of settlement limit states. The decisive criterion was the compressive strength of concrete.
DOI: 10.22227/1997-0935.2016.1.35-43
Pages 44-56
OF INSTALLATION Computer analysis of the values of the initial forces due to force elimination of assembly errors of double-layer framed metal dome has been performed. The position errors of nodes of pair meridional ribs were considered in the normal and meridional directions at installation of the dome frame with temporary central support. For selected nodes concentrated forces were applied to eliminate the relative deviations of adjacent ribs and the resulting internal forces in the bars were registered. The values of these internal forces were compared to the forces in bars resulting from the dead load and design load. The results of the investigation are presented in the form of figures, diagrams, tables and graphs. Based on the analysis of the data obtained, conclusions are made about the influence of initial forces on the stress state of the frame of the dome.
DOI: 10.22227/1997-0935.2016.1.44-56
Pages 57-67
An earthquake is a rapid highly nonlinear process. In effective normative documents there is a coefficient K1, which takes into account limit damage of building structures, i.e. non-linear work of building materials and structures during seismic load. Its value depends on the building constructive layout. However, because of the development of construction and new constructive solutions this coefficient should be defined according to design-basis justification. The article considers the five-storey building calculation on seismic impact by linear-spectral and direct dynamic methods. Our research shows that the coefficient K1 for this building is 0.4, which was calculated using nonlinear dynamic method. According to effective normative documents K1 is 0.25…0.3 for buildings of this type. Thus we get a lack of seismic stability of bearing structures by 1.5…2 times. In order to ensure the seismic safety of buildings and facilities, especially of unique objects, the coefficient K1 should be determined by calculations with sufficient scientific justification, particularly with the use of non-linear dynamic methods.
DOI: 10.22227/1997-0935.2016.1.57-67
Pages 68-79
The mechanical (structural) reliability of a building, safety of people and continuity of the technological processes in buildings and structures depend on the reliability of the bearing structures on operation stage, including reinforced concrete beams. One of the measures to provide safety and reliability is the probability of no-failure operation of structural elements or systems of elements. For reliability calculation the Russian State Standard recommends to apply probability and statistical methods when possessing enough data on variability of the controlled parameters in the mathematical model of the limit state, in particular, when the amount of data allows conducting its statistical analysis. In the current time there appear the works pointing, that the future advancing of calculation methods for building structures requires the wide use of reliability theory. The article describes the methods for calculating the reliability of a reinforced concrete beam according to the criterion of crack length with the limited statistical information about controlled parameters. The authors illustrate the application of the theory of evidence to determine the statistical mathematical expectation of reliability in the presence of a subset of reliability intervals. Each design case is followed by numerical examples. The article underlines the importance of applying fracture mechanics for the further development of the methods of calculation of reinforced concrete structures.
DOI: 10.22227/1997-0935.2016.1.68-79
Pages 80-93
DOI: 10.22227/1997-0935.2016.1.80-93
Pages 94-104
The modern tendencies of construction industry development are connected with the use of new high-efficient materials with the application of resource- and energy-saving technologies of their generation. The use of industrial man-made products as the components improving the characteristics of construction products is now a promising field of research. The article presents the results of the use of waste pickling solutions of steel rolling factories, containing salts of iron as nanomodified additives for the products based on cement binder. The effectiveness of the influence of the considered additives on the structure and strength of fine-grained concrete is shown. If using this additive in the amount of 0.32 % from the mass of cement for 28 days of natural hardening, the fine concrete strength is growing by 1.8 times due to additional formation of hydrosilicates, densification of structure and reduction of the total porosity of the cement system by 2 times.
DOI: 10.22227/1997-0935.2016.1.94-104
Pages 105-117
At the present time industrial waste is considered to be an alternative to primary natural resources when producing construction materials and products. The use of industrial waste in the construction branch allows reducing ecological load on the environment and population as a result of reducing the amount of unrecyclable waste and reducing the use of primary natural resources. Though when involving waste products as raw material in the preparation of building materials there occur environmental risks of anthropogenic impact increase on the environment. These risks are related to possible emission of heavy metals from construction materials in use. The article describes a tool which allows predicting this issue, depending on the acidity of the medium, the residence time of the material in the environment. The experimental data obtained in determining the migration activity of metals from cement concretes to aqueous solutions served as the basis for the mathematical model. The proposed model allows us to make a prediction of anthropogenic impact on the environment and commensurate this impact with the possibility of assimilation of the environment area where the building materials are applied. This will allow conducting an effective assessment of the created and applied technologies of waste disposal, taking into account the operating conditions of the materials produced.
DOI: 10.22227/1997-0935.2016.1.105-117
Pages 118-125
Currently, the successful development of construction industry depends on the improved energy performance of buildings, structures and facilities, as well as on the quality assurance of the indoor climate. The approximate calculation of two-dimensional temperature field of the ground outside the underground part of the building is considered using the analytical solution of differential equation of thermal conduction by the method of sources and sinks according to the existing boundary conditions. This problem is a very high-priority task now because of actualization of building standards in Russian Federation and because of the increasing demands to safety and security of heat supply. That’s why it is very important to find a simple but accurate enough dependence for the heat losses through the floor situated on the ground. The results of the estimation of thermal resistance of floor areas on the ground are presented on the basis of the obtained temperature field. The comparison of these results with the regulatory requirements specified in SP 50.13330.2012, and with the data of numerical calculations of other authors using finite difference approximation of the thermal conduction equation with consideration of soil freezing is held. It is shown that the requirements of the SP 50.13330.2012 are physically reasonable, and numerical calculations can also be described by the analytical dependence obtained in this paper with appropriate selection of the numerical coefficients with the preservation of engineering form of the calculation procedure. The obtained model is easy to use in engineering practice especially during preliminary calculations. The presentation is illustrated with numerical and graphical examples.
DOI: 10.22227/1997-0935.2016.1.118-125
Pages 126-142
In a flat solar collector SUN 1 The active development of environmental friendly energy sources alternative to HPPs is currently of great importance in the world. Such alternative energy sources are: water, ground, sun, wind, biofuel, etc. If we have a look at the atlas of solar energy resources on the territory of Russia, we can make a conclusion, that in many regions of our country solar activity level allows using solar collector. Though the analysis of different models of solar collector showed, that most of them are ineffective in the regions with cold climate, though the solar activity of these regions is of a great level. In this regard, a mathematical model of heat-mass exchange processes in flat solar collectors is introduced in this article. The model was a basis for the development of a new solar collector, named SUN 1, which has an original heating tubes form. This form allows heat transfer medium to be under the influence of solar energy for a longer time and consequently to warm to a higher temperature, increasing the warming rapidity.
DOI: 10.22227/1997-0935.2016.1.126-142
Pages 143-149
Earth dam with impervious element in the form of asphaltic concrete core is currently the most promising type of earth dams (due to simple construction technology and universal service properties of asphaltic concrete) and is widely used in the world. However, experience in the construction and operation of high dams (above 160 m) is not available, and their work is scarcely explored. In this regard, the paper discusses the results of computational prediction of the stress-strain state and stability of a high earth dam (256 m high) with the core. The authors considered asphaltic concrete containing 7 % of bitumen as the material of the core. Gravel was considered as the material of resistant prisms. Design characteristics of the rolled asphaltic concrete and gravel were obtained from the processing of the results of triaxial tests. The calculations were performed using finite element method in elastoplastic formulation and basing on the phased construction of the dam and reservoir filling. The research shows, that the work of embankment dam with vertical core during filling of the reservoir is characterized by horizontal displacement of the lower resistant prism in the tailrace and the formation of a hard wedge prism descending along the core in the upper resistant prism. The key issue of the safety assessment is to determine the safety factor of the overall stability of the dam, for calculation of which the destruction of the earth dam is necessary, which can be done by reducing the strength properties of the dam materials. As a results of the calculations, the destruction of the dam occurs with a decrease in the strength characteristics of the materials of the dam by 2.5 times. The dam stability depends on the stability of the lower resistant prism. The destruction of its slope occurs on the classical circular-cylindrical surface. The presence of a potential collapse surface in the upper resistant prism (on the edges of the descending wedge) does not affect the overall stability of the dam.
DOI: 10.22227/1997-0935.2016.1.143-149
Pages 150-160
In the article the authors carried out a statistical analysis of mass determination of the filtration coefficient, which allows us to construct the most accurate calculation model of seepage field of inhomogeneous bedrock foundation of the dam needed for seepage calculations and to predict seepage regime of hydraulic structures and their grounds. The algorithm can be applied to analyze heterogeneity based on the large set of definitions of the properties of soil, subject to the condition that within the engineering geological element of random fluctuations of the index properties or some of its functions, e.g., logarithm of index properties, obey normal distribution law. In the latter case, all digital values of the index should be recalculated and presented in the form, in which they submit to the law of normal distribution. The authors received effective evaluation of the filtration coefficient on the basis of the law of statistical distribution. Correspondence of each component to a particular genetic element of the array is derived from the premise, adopted prior to the mathematical analysis: we divided the total distribution into separate normal distributions, and normal distribution is only true for a genetically separate engineering-geological element. After finding boundary values of the distributions it is required to determine the cut regions, in which relevant engineering-geological elements are localized, with the help of specially designed algorithm. In order to clarify geological distinction between the various lithological zones, zones of weathered and fractured zones, we use numerical data of filtration sampling. Then we put the numerical values of the index properties of lgq on which segmentation of the array occurs, on a geological cross section, respectively, for each well. After assigning numerical codes to the individual values of the indicator properties you can begin to image the geological section, where we combine the intervals with identical key values in the second position of the code. The boundaries between the drilled wells are held on a Pro forma basis for geological reasons. For example, if the set of values with the largest number lgq, which corresponds to the species with a visually perceptible change when exposed to weathering, has a number 4, the boundaries between the drilled wells will naturally stretch along the roof of the bedrock. If according to the proposed methodology, within the limited element number 4, the interval is flagged with number 3, it can be interpreted as the appearance of the outcrop of other rocks. In this case we need to show the boundary of engineering-geological element with a smaller value of lgq around the 3, than it is inside the engineering-geological element number 4. For each of the obtained groups of values, calculated using known statistical formulas, we calculated the mean value and other statistical estimates that are useful in practice. For example, the geometric mean is an effective in a hydraulic sense evaluation of the specific absorption coefficient of the filter. So the authors proposed a formalized approach to defining the structural elements of the filtration field inhomogeneity of a rock mass of hydraulic structures foundation on the basis of statistical analysis. The article shows how to highlight the engineering-geological elements with the filtration inhomogeneity of rocky soils on the example of the Boguchanskaya HPP on the Angara River.
DOI: 10.22227/1997-0935.2016.1.150-160
Pages 161-169
Due to the influence of many different factors, the arrival of vehicles to technical inspection lines is stochastic. The existing methods of designing the network of technical inspection do not take full account of this fact, the consequence of which is the lack of inspection lines load at some periods of the year and its excess in the other. In the first case, we evidence the deteriorating of economic performance of these facilities, in the second - the quality of evaluating the technical condition of vehicles suffers. The authors proposed a method of justifying the minimum requirements of residential areas in the lines of technical examination, taking into account the probabilistic nature of vehicles inspection revenue. The use of the proposed method was shown on the example of a large village. Using the mathematical apparatus for calculation of queuing theory allows not only identifying the areas in need of inspection lines, but also, if necessary, providing technical and economic evaluation of the results obtained by calculations.
DOI: 10.22227/1997-0935.2016.1.161-169
Pages 170-180
One of the tasks a construction complex is facing today is the transition to innovative technological form. New efficient mechanisms of management of its innovative development are needed. It is necessary to involve specialized engineering companies rendering the services in innovative engineering into innovative activity management of the organizations of a construction complex. Within these services we offer the use of new administrative instrument of “innovative leasing engineering”. In the article the functions of the engineering companies carried out within this instrument of innovative development of a construction complex are offered and proved. The management process of risks in this sphere is considered. Classification of risks of innovative leasing in a construction complex is specified. The risks of a managing director of an engineering company are revealed and proved; the risks of other participants of the leasing relations are specified. New approach to decrease the risks of innovative leasing with participation of the managing director of an engineering company is offered on the basis of the methods of risks distribution between the participants of the leasing relations, insurance and hedging of risks.
DOI: 10.22227/1997-0935.2016.1.170-180
Pages 181-191
At the present time all over the world the main concept of life cycle maintenance of complex objects is the use of data-centric information systems of engineering data management, which allow providing support of the correspondence of an object configuration to its present state. The central part of such a system is a 3D information model of the object. The information model has a fundamental advantage in comparison with typical user applications - presence of complete and up-to-date data on industrial object topology. The authors consider the practical use of information modeling technologies for solving the tasks of engineering data management on a large industrial facility on all the stages of the lifecycle: from design to utilization. Such Russian solutions are investigated as: 3D CAD POLYNOM - to create 3D model of an object, PLM/PDM-platform NEOSYNTEZ - to provide engineering data management on all the stages of the lifecycle and a software product InterBridge - to translate graphical and semantic 2D/3D data between CAD and PLM of different platforms.
DOI: 10.22227/1997-0935.2016.1.181-191