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Presently, no uniform methodology of identification of optimal costs of construction of gas distribution networks is available. The amount of work, and, hence, its cost, are identified empirically; therefore, they are insufficiently substantiated by feasibility studies. At best, the problem of optimization is reduced to simple examination of various options.
The problem to be resolved by the method of search optimization may be stated in the following manner:
Two consumers are to obtain access to the gas supply. Their positions in the arbitrary coordinate system are available (; ). The high pressure gas distribution line of a gas distribution network is located at some distance from the aforementioned consumers. It can be represented as follows: = +. Gas control unit installation is required to assure gas pressure reduction.
Goal 1: positioning of a gas control unit to assure the lowest possible cost of the gas distribution network construction.
Goal 2: solution to the above problem turns more complicated, if the line of the gas distribution network required to connect the designed gas pipeline extension is long. In this case, besides the identification of the optimal coordinates of a gas control unit, it is also necessary to find the point of connection to the gas control unit, for the cost of the gas distribution network to be as low as possible.
Goal 3: some sections of gas distribution networks pass through or over natural or artificial barriers. In the event of such restrictions, the search for the optimal point of connection to the gas control unit turns more labor-intensive and challenging.
To sum up the above statements, the authors demonstrate that rational design of gas distribution networks brings essential economic benefits.

Heat-insulating cellular concrete manufactured in the variotropic pressure environment, may be used both for making single-piece products, and for monolithic construction purposes. Optimization of technology-related parameters prevents excessive consumption of principal components, while output products maintain pre-set characteristics. Both the product and the technology are based on the provisions of the general methodology of development of highly porous materials.
The technology is based on the principle of adjustable formation of the state of stress in the variotropic pressure environment. The state of stress maintained in the course of blowout contributes to formation of optimized cellular structure (in accordance with the criteria that include the shape, dimensions of pores, and characteristics of interpore partitions).
The process of manufacturing of the heat-insulating cellular concrete breaks down into the following stages: preparation of raw materials, preparation of the cellular concrete mixture, casting of products, thermal processing or ageing in the natural environment. Products are placed under heating domes, equipped with electric heaters, and exposed to heat treatment for six hours. Before the heat treatment, products are kept in their moulds for four hours. In the absence of heat treatment, products are kept on their pallets for 14 days.
Selection of the appropriate composition and optimal technological parameters is performed with the help of G-BAT-2011 software programme developed at MSUCE. The software is based on the methodology that is based on complete factorial experiments, experiments based on fractional replicates and testing of all essential statistical hypotheses. Linear, incomplete quadratic and quadratic equations generated as a result of experiments make it possible to design a model that represents natural processes in the adequate manner. The model is analytically optimized and interpreted thereafter.

The factors of impact onto the process of selection of the optimal method of renovation of pressure and pressure-free pipes are considered in the article. The programme algorithm, input and output user information, the sequence of actions within the framework of the user-to-software interaction are presented, and the optimal renovation method is provided. The software programme is designated for researchers, designers and specialists of construction companies and design firms.
The output data are arranged as a bar chart that covers the cost of work, the timing of work, as well as the time, technology and hydraulics-related factors that impact the choice of a trenchless renovation method characterized by the smallest average-weighted indicator.

In the article the authors describe a method of optimizing the stress state of an elastic beam, subject to the simultaneous action of the central concentrated force and bending moment. The optimization method is based on solving the inverse problem of the strength of materials, consisting in defining the law of changing in elasticity modulus with beam cross-section altitude. With this changing the stress state will be preset. Most problems of the elasticity theory of inhomogeneous bodies are solved in direct formulation, the essence of which is to determine the stress-strain state of a body at the known dependences of the material elastic characteristics from the coordinates. There are also some solutions of the inverse problems of the elasticity theory, in which the dependences of the mechanical characteristics from the coordinates, at which the stress state of a body is preset, are determined. In the paper the authors solve the problem of finding a dependence modulus of elasticity, where the stresses will be constant over the beam’s cross section. We will solve the problem of combined strength (in the case of the central stretching and bending). We will use an iterative method. As the initial solution, we take the solution for a homogeneous material. As the first approximation, we consider the stress state of a beam, when the modulus of elasticity varies linearly. According to the results, it can be stated that three approximations are sufficient in the considered problem. The obtained results allow us to use them in assessing the strength of a beam and its optimization.

Arch structures of long span buildings’ coverings are more beneficial in respect to material expenses, than beam and frame systems. Constructive schemes of roof frameworks of arch coverings are diverse, which means their operation under loading differs much. The authors offer a number of construction solutions for flat arch coverings of long span buildings. The comparative analysis of these construction solutions is presented. The operation of radial link arch is observed. The arch consists of discontinuous top chord and radial bowstring under the single load (uniformly distributed and concentrated in nods) with different spans and rises. The problem of radial link arch optimization is solved in dependence with arising forces and rise. The optimal camber of arch was found. In further works the authors plan to analyze spans more than 36 meters and solve the problem in case of asymmetrical loadings.

The optimization of the construction solutions for building structures is obviously reasonable because in case of making optimal solutions the cost of construction and further operation can be essentially cut. Relatively small changes in construction solutions may lead to essential changes on the stage of construction and operation. According to the traditional approach a designer usually develops a limited number of variants, consideration of which doesn’t guarantee the closeness of the final result to optimum. That means, the problem of the development of new and optimization of the existing optimization methods for design solutions remains current. The article is devoted to the current problems of choosing the optimal design solution for steel structures of industrial buildings. The authors offered an algorithm for computer-aided design and obtained a design solution on the example of a truss implemented in PC ANSYS. As optimization variables the truss height, steel grade and element section type are considered. The algorithm allows determining the value of the minimum truss weight for trusses of various classes and types of section. Also the corresponding optimum truss height is estimated, which gives a minimum design weight for different types of sections.

The authors have employed analytical methods to identify the nature of dependence of the elastic modulus distribution over the thickness of a cylinder, loaded by internal pressure p , if the equivalent stress is the same in all points, according to Mohr’s theory of strength. The problem in which dependence of an elastic modulus is to be identified along the radius, and the stress value is available, is called the inverse prob- lem. The idea of the method is that if a certain area of a body has the value of its elastic modulus lower than the one in the homogeneous material, stresses in this area are also reduced. The problem is solved for the case of plane strain and plane stress in the elastic formulation. It is proven that assurance of artificial heterogeneity reduces the maximal equivalent stress. Therefore, we have taken two variants of shells: one having inner radius a = 1 m and outer radius b = 2 m, the other one having inner radius a = 1 m and outer radius b = 0.52 m. The value of the maximal equivalent stress calculated using Mohr’s theory reduces almost two-fold in the first case and 1.5-fold in the second case. Moreover, the use of non-uniform thick-walled cylinders can significantly reduce their thickness with the value of the internal pressure being the same. In our case, the shell thickness reduces from 1 m to 0.52 m, which is almost 2 times. We also proven that the first, second and third strength theories in the case of an axisymmetric problem are the special cases of Mohr’s strength theory. This result coincides with well-known analytical and numerical solutions.

The gathered experience of design and construction of objects with the use of grid structures confirms the expediency, efficiency and flexibility of their minimum technical solutions providing increased strength and resistance to progressive collapse. From the general range of modern metal designs using shaped tubes (bent and welded profiles) the article observes blocks of roofs and ceilings made of cross-type farms «Pyatigorsk» as the most step-ahead solutions. Due to the small size they are conventionally classified as «pocket» modules produced all-welded. Prospects of the use of shaped tubes of round and oval cross-sections for further modernization of farms and other cross-lattice structures are presented. The article demonstrates quite acceptable accuracy and ease of optimization calculation of oval cross sections according to an approximation method. The authors describe a new technical solution for lattice structures, which contributes to the improvement of their technical and economic characteristics. Reduction in the consumption of structural material when implementing such a solution is discovered by the example of roof trusses, as well as increase of the reliability and structural safety of buildings and structures by approximation of lattice structures to their design schemes (models) in the form hinged-rod systems.

New technical solutions relating to triangular (three-chord) trusses for roofs (floors) are presented. In one of them for compressed-flexural elements of chords, Z-shaped built-up sections made of paired angle bars of assortment of structures of the TsNIISK, Moskva types are used instead of double-tee sections. In another solution, for gussetless nodal connections of rectangular tubes, the centering of these nodes on the ribbing of elements of chords with a V-shaped preparation of tip edges of elements of webs is used. For steel triangular roof trusses, optimal dimensions of their depths for which the usage of constructional material is minimal are given. These dimensions are 1/20...1/12 of the span and are obtained from the equality of masses of chord and web elements, taking into account the optimal inclination angles of braces. Acceptable convergence of the obtained results confirmed by the experience in the design of prestressed truss structures and optimization of structural designs of the TsNIISK type, taking into account new changes of boundary conditions, is shown. Sphere of effective application of the considered structures is defined. Thus, it can be concluded that the proposed technical solutions as to the triangular trusses for roofs (floors) are quite rational and promising for use in load-bearing structures of buildings and installations, and the optimization of depths of such trusses generalizes, to a certain extent, the widespread practice of calculating and designing thereof. The sphere of effective application of the considered triangular trusses can include lightweight metallic structures made of closed roll-welded sections (shaped tubes), rolled shapes and slender galvanized sections. Constituent part of this sphere can be presented by triangular (three-chord) trusses, shaping space frame systems in a form of space frames (see Fig. 1, а ) or crossed (see Fig. 5, в ) structures, and the technical and economic characteristics of these structures can be significantly improved due to rigid discs made of composite (steel reinforced concrete) slabs with permanent formwork and external reinforcement.

Many elements meet in nodes of spatial lattice structures. The node of such structure works in a complicated stressed state. Experimental methods traditionally used for assessment of the stress-strain state of nodals connections, give only approximate results, and for structures with complex geometry are generally useless. It is possible to study a distribution of stresses inside the nodal connector, which is a massive body, using calculation software packages. As a result of calculation of a model of nodal connection in the CosmosWorks environment, stresses both on the connector’s surface and inside of it were obtained. The authors carried out the research of a stress-strain state of the MArchI (Moscow Institute of Architecture) system node and performed the analysis of the level of surface stresses and stresses inside the nodal connector. On the basis of the fulfilled research, conclusions on the work of the nodal connector were drawn: stresses on the connector’s surface do not generally exceed the conventional yield strength of steel; maximum values thereof are observed on the reference plane and at points of contact of a nut and the connector; distribution of material for the given geometry of connector turned out to be rational; it is possible to reduce the volume of steel for the nodal connector by way of changing its conceptual design, for example, having considered the issue of formation of the node out of a hollow shell.

Ceramic technology is based on three requirements: maintaining the product properties on the required level, reduction of energy costs, optimization of raw materials consumption and technological parameters. It is possible to obtain a product with improved operating abilities, at the same time optimizing the energy consumption, with the use of modern methods of thermal treatment, which include a combination of burning mechanisms in one technological conversion.The service durability of products is determined by the simultaneous influence of the factors, which are characterized by the properties of raw materials, the conditions of molding powder preparation, molding and thermal treatment. The usage of innovational technological methods allow to reduce the duration of the main energy consuming operations — the process of powder preparation can be reduced from 8—12 hours (traditional technology) up to 2—3 minutes, and the process of drying and burning from 2—3 days to 1—1.5 hours. The quality of ready products remains high.Ceramic tiles are primarily used as finishing material in the construction of residential, public and industrial buildings. Modern technologies of ceramic tiles provide not only crock glazing, but also applying other materials on it. This can extend the range of ceramic tiles application.

Modern humanity development is impossible without scientific and technological progress, energy, industry, transport. Despite the fact that industrialization and the constant increase of production capacity have helped people to expand their limits significantly, we should not forget that today our dependence on the established infrastructure is steadily increasing. It is most vivid in case of natural hazards or disasters, which lead to disruption of normal living conditions. Any of these negative phenomena is called "emergency situation". However, the occurrence of emergency situations in life support systems leads to the following negative consequences: disorganization of life support systems functioning on the object, local, regional, national levels; exclusion or complete destruction life support systems; partial or complete reduction of the opportunities for ensuring the needs of the population; danger to life and health of the population. Despite the considerable number of scientific publications, many theoretical and methodological aspects of creating mechanisms and resistance patterns of objects and systems require further investigation that is due to: the possibility of emergency situations doesn’t decrease; acceleration of scientific and technical progress; existing threat of war together with the continuous improvement of weapons; threat of terrorist acts, etc. The authors present a research of the opportunity to construct a sustainability model of life support systems under different emergency situations in respect of modern current trends in the development of information-analytical systems and principles of systems engineering approach. The development of a general stability model, in that case, must consider common sequence of actions, ranging from signs of disaster to the recommendations for eliminating its consequences for life support systems, and the issues of effective interaction between individual subsystems involved in this process at all stages.

Today the technologies of trenchless reconstruction of pipelines are becoming
more and more widely used in Russia and abroad. One of the most perspective is methods is shock-free destruction of the old pipeline being replaced with the help of hydraulic installations with working mechanism representing a cutting unit with knife disks and a conic expander. A construction of a working mechanism, which allows making trenchless reconstruction of pipelines of different diameters, is optimized and patented and its developmental prototype is manufactured. The dependence of pipeline cutting force from knifes obtusion of the working mechanisms. The cutting force of old steel pipelines with obtuse knife increases proportional to the value of its obtusion. Two stands for endurance tests of the knifes in laboratory environment are offered and patented.

Nowadays in Russian Federation there is a growing demand for monolithic construction. Monolithic construction technology is developing to meet the requirements, such as reduction of construction time and improvement of the quality of the structures. Analysis of different situations that arise on construction sites shows a number of usual problems: increased construction period, increased cost, etc.Possible reason of this problem can be in using outdated approaches to the control of monolithic construction processes. Such approaches do not take into account deviations due to the abrupt changes caused by external influence of the environment. And it can lead to increase in technological expectations or increase in labor costs for eliminating these deviations. This article presents an approach, which helps to increase the efficiency of process organization in monolithic construction by means of adaptive control and operative control in real time. This approach is based on the methods of operative monitoring and processing of information about the state of the production system at any given time. In this paper organizational scheme for combining different production and control processes was developed, which is based on the following principles: Choice of criteria for comprehensive assessment of a production system, that reflect both internal state and external disturbances; Development of the methods and means of operational monitoring of the structures(includes previously selected criteria); Development of the methods of constructing situation models of the production system functioning (including modeling the hydration process of concrete and the influence of external factors on this process).Development of the methods of research and information decision support based on automated processing of information, obtained in the course of monitoring, and on the analysis of available options of controlling actions.

Materials consumption rate is used by many authors as the criterion for the assessment of the economic efficiency of gas distribution networks in the course of their design. No doubt that control over the materials consumption rate is of particular importance. However, we believe that it represents one of several constituents of the overall cost of a gas network piping project. Labour expenditures and earth works that are, to some extent, dependent on the diameter of a pipeline, should also be taken into account. Presently, metal and polyethylene pipes of standard diameters are used in gas network development projects. Diameters of pipes of external gas distribution networks are rounded up to the closest standard diameter of pipes as a result of a hydraulic calculation.
The cost of construction of a gas pipeline has multiple constituents that may be clustered into three principle groups:
1) earth works,
2) piping;
3) cost of materials.
Calculation of the cost of construction of low and medium pressure pipelines to be made of steel and cross-linked polyethylene was performed to find out the cost of a pipeline.
The calculations were made in the basic prices of the year 2000 adjusted to the figures of April 2011, given the standard piping conditions in a settlement within central Russia. The data were interpolated by means of a quadratic function.
On the basis of the above data, a comparative analysis of capital expenditures in respect of steel and polyethylene piping may be performed.
The research also contemplates the structure of expenses associated with the piping of gas distribution networks. Mathematical equations have been derived to perform sufficiently accurate calculations of costs of construction of various types and various lengths of gas pipelines.

Planning and implementation of innovations on the microlevel of management and on the higher levels is a process of innovative projects portfolio implementation. Project management is aimed at some goal; therefore, defining the mission and aims of implementation is of primary importance. These are the part of the notion of development strategy of an enterprise. Creating a strategy for big construction holding companies is complicated by the necessity to account for different factors effecting each business-block and subsidiary companies. The authors specify an algorithm of development and implementation of the activity strategy of a big construction enterprise. A special importance of the correspondence of organizational management structure to the implemented strategy is shown. The innovative character of organizational structure change is justified. The authors offer methods to optimize the organizational management structure based on communication approach with the use of the elements graph theory. The offered methodological provisions are tested on the example of the Russian JSC “RZhDstroy”.

One of the problems of construction planning is failure to meet time constraints and increase of workflow duration. In the recent years informational technologies are efficiently used to solve the problem of estimation of construction period. The issue of optimal estimate of the duration of construction, taking into account the possible organizational expectations is considered in the article. In order to solve this problem the iteration scheme of evolutionary modeling, in which random values of organizational expectations are used as variable parameters is developed. Adjustable genetic operators are used to improve the efficiency of the search for solutions. The reliability of the proposed approach is illustrated by an example of formation of construction schedules of monolithic foundations for buildings, taking into account possible disruptions of supply of concrete and reinforcement cages. Application of the presented methodology enables automated acquisition of several alternative scheduling of construction in accordance with standard or directive duration. Application of this computational procedure has the prospects of taking into account of construction downtime due to weather, accidents related to construction machinery breakdowns or local emergency collapses of the structures being erected.

The article describes virtual organizational structure for the construction industry, which was formed as a result of a number of problematic issues. The development of the construction industry is one of the prior tasks for the state economy. Virtual enterprises, tailored to the industry, showed themselves as the most progressive means of production optimization and automation.Virtual organizational structures are becoming more widespread. They demonstrate positive effect after being introduced and used in various sectors of the economy. Today, foreign experience and technologies of implementing virtual organizational structures of enterprises is actively adapted in the realities of the Russian economy with harsh investment climate and the increased interest of the state sector. The introduction of virtual organizational structures for construction companies is a significant step in the process of the industry informalization. By setting a precedent and reinforcing it by appropriate methodological framework, we obtain a basis for the formation of information platforms, which contain the full list of theoretical and practical knowledge.Getting positive effect after creating virtual organizational structures of enterprises in the construction industry is only half the way. Any result from the introduction will result in a new area for research and development.

The article focuses on the optimization of the earlier discussed computer method of obtaining new forms of polyhedra based on projective geometry drawings (trace Diagrams).While working on getting new multifaceted forms by projective geometry methods based on the well-known models of polyhedra on the first stage of the work it is required to calculate the parameters of projective geometry drawings, and then to build them. This is an often used apparatus of analytical geometry. According to it, at first the parameters of the polyhedron (core system of planes) are calculated, then we obtain the equation of the plane of the face of the polyhedron, and finally we obtain the equations of lines the next plane faces on the selected curve plane. At each stage of application such a method requires the use of the algorithms of floating point arithmetic, on the one hand, leads to some loss of accuracy of the results and, on the other hand, the large amount of computer time to perform these operations in comparison with integer arithmetic operations.The proposed method is based on the laws existing between the lines that make up the drawing - the known configurations of projective geometry (complete quadrilaterals, configuration of Desargues, Pappus et al.).The authors discussed in detail the analysis procedure of projective geometry drawing and the presence of full quadrilaterals, Desargues and Pappus configurations in it.Since the composition of these configurations is invariant with respect to projective change of the original nucleus, knowing them, you can avoid the calculations when solving the equations for finding direct projective geometry drawing analytically, getting them on the basis of belonging to a particular configuration. So you can get a definite advantage in accuracy of the results, and in the cost of computer time. Finding these basic configurations significantly enriches the set of methods and the use of projective geometry drawings.

The modern transport system is a complex integrated object, which includes various road pavements, different technical means to provide vehicles motion, organizational systems of traffic management. In the contemporary conditions of construction industry functioning the task to create vehicle systems is of a great economic importance. Great labour and material resources are used for production of transport means for providing construction works and operation of these means. The authors consider the questions of theoretical and informational foundation development for the formation of the criteria basis of investment optimization task during construction of automatical and informational systems for increase of traffic safety in transport systems, providing zero accident rate.