In the article the requirements for fire safety assurance are justified for the objects, in which water is supplied with account for serial and parallel area zoning. In the process of zoning the district is segregated into such parts, for which head rate in any point of selection of water from network will not exceed 6 bar. In the current regulatory rules the requirements for the calculation of the costs of water points are stated, as well as in case of extinguishing fires at the sites with water-supply systems zones. It is recommended to analyze each zone of the system of water-supply separately, without interrelation with the common water feeders, water consumers and services of fire extinguishing. Such an approach to assign water discharge for fire extinguishing results in the decrease of fire safety of an object, deforms calculation technique of outside systems of water-supply of the similar-type objects located in different parts of the terrain. Taking the number of fires and water consumption for fire suppression by the number of residents in each zone, we thus underestimate the capacity of the pipeline system. It is offered to make changes in Norms and Standards in force on fire safety of settlements. The recommendations on regulation of the number of fires and water flow for fire fighting in residential objects with zoned systems of water-supply are formulated.

Russian manorial estate, the importance of which for the Russian culture can scarcely be exaggerated, is an original and many-sided phenomenon, in which all socio-economic, historical and cultural processes of Russia are focused. Having come into being as dwelling and house-hold complexes, the estates gradually formed cultural framework of Russia in the period from the middle 18th to the end of 19th centuries. In connection with changing social conditions taking place in the 20th century and the loss of their primary meaning only the small part of the estates is conserved today and we are standing at the edge of loosing this invaluable layer of our cultural heritage. In recent years the attempts to revise our history have given positive improvement of public treatment of our historical and architectural heritage. As a result the public interest to the national phenomenon of estates provoked strong impulse to study and to accumulate information about them, but unfortunately did not answer the question how to use this heritage under present-day conditions. The legislation changes recently and the creation of programs and nonstate charitable funds give the hope for the positive improvement in the reconstruction of estates and involving them in the contemporary life. Possible variants of usage of historical settlements as well as estate and park complexes having the great scientific and cognitive and architectural value are considered. The revival of the historical estates together with the national cultural traditions is still not developed enough, but it is an inexhaustible source for the economical and cultural development of Russian regions.

In the article, the co-authors analyze the findings of the experimental and theoretical studies into the real behaviour of a thin-walled cold-formed purlin as part of the roof structure made of sandwich panels. The roof structure fragment was tested; displacements and stresses, that the purlin was exposed to, were identified in respect of each loading increment. NASTRAN software was employed to perform the numerical analysis of the roof structure, pre-exposed to experimental tests, in the geometrically and physically non-linear setting. The finite element model, generated as a result (the numerical analysis pattern), is sufficiently well-set, given the proposed grid of elements, and it ensures reasonably trustworthy results. The diagrams describing the stress/displacement to the load ratio and obtained numerically are consistent with those generated experimentally. The gap between the critical loading values reaches 4%. Analytical and experimental findings demonstrate their close conformity, and this fact may justify the application of the numerical model, generated within the framework of this research project, in the course of any further research actions. The co-authors have identified that the exhaustion of the bearing capacity occurs due to the loss of the buckling resistance as a result of the lateral torsional buckling.

In the article, the author shares his classification of FEM statements that may serve as a guide in respect of the huge number of works that are published and being published with a view to the FEM efficiency improvement. The author provides a summarized history of the finite element method, and classifies its configurations and versions. The author also provides FEM statements applicable to the deflection method. Derivation of the rigidity matrix designated for shaft-based finite elements is demonstrated in the article. The author employs one-dimensional framing as an example aimed to demonstrate the convergence of the FEM method in terms of deflections, if the finite element grid is refined. However it is also noteworthy that in the event of a fine grid, the finite element designed for plates does not coincide with the finite element of a thin plate designed as the initial physical model. However, the system of equations, provided by the author, takes account of the influence produced by the load onto the finite element and generates the exact solution irrespective of any finite values of the length that are equal to the physical model of a finite element.

In the article, the author has proven that manufacturing and installation errors, as well as contact deformations of high strength bolts, if analyzed as part of tensile connections of steel structures, work in eccentric tension. In pursuance of the effective state standards, the analysis of these bolts is based on the axial tension. The author has analyzed the failure of a steel structure, caused by the fracture of eccentrically loaded bolts made of steel grade XC 42 (France), or C40 (Germany), that later followed the delayed fracturing pattern. The author provides the findings of the lab tests, whereby the above bolts were tested in the presence of an angle washer. The author has also analyzed the findings of low-temperature tests of bolts in tension. The author demonstrates that the strength of high strength bolts is driven by the material, the structure shape, and the thermal treatment pattern. Eccentric tension tests of bolts have proven that cracks emerge in the areas of maximal concentration of stresses (holes in shafts, etc.) that coincide with the areas where fibers are in tension; cracks tend to follow the delayed fracturing pattern, and their development is accompanied by the deformation-induced metal heating in the fracture area. Therefore, the analysis of high strength bolts shall concentrate on the eccentric tension with account for contact-induced loads, while the tendency to delayed fracturing may be adjusted through the employment of both metallurgical and process techniques.

In order to find eigenfunction of the Laplace operator in regular
n+1-dimensional simplex the barycentric coordinates are used. For obtaining this result we need some formulas of the analytical geometry. A similar result was obtained in the earlier papers of the author in a tetrahedron from
R
³ and in gipertetrahedron from
R
⁴. Let П be unlimited cylinder in the space
R
ⁿ, its cross-section with hyperplane has a special form. Let
L be a second order linear differential operator in divergence form, which is uniformly elliptic and η is its ellipticity constant. Let
u be a solution of the mixed boundary value problem in Π with homogeneous Dirichlet and Neumann data on the boundary of the cylinder. In some cases the eigenfunction of the Laplace operator allows us to continue this solution from the cylinder Π to the whole space
R
ⁿ with the same ellipticity constant. The obtained result allows us to get a number of various theorems on the solution growth for mixed boundary value problem for linear differential uniformly elliptical equation of the second order, given in unlimited cylinder with special cross-section. In addition we consider
n-1-dimensional hill tetrahedron and the eigenfunction for an elliptic operator with constant coefficients in it.

The author comes up with a refined mathematical model contemplating that added mass facilitates interaction between coupled flexural and radial vibrations in the linear setting. The author has identified a higher splitting of the flexural frequency spectrum due to the presence of the added mass and the wave generation parameters that characterize the relative length and thickness of the shell. Within the framework of the shallow-shell theory, the influence of the small concentrated mass onto natural dynamic properties of the shell is exposed to research. The refined mathematical model was employed to identify that the added mass binds the coupled flexural shape of the circular cylindrical shell and facilitates interaction between low-frequency flexural vibrations and high-frequency radial vibrations. Moreover, radial vibrations act as a supplementary inertial link between coupled flexural shapes. Due to the availability of the exciting load, non-resonant areas, identified through the application of the traditional mathematical model, can be resonant in essence. The findings of this research must be considered in the course of the assessment of the dynamic strength of any shell structures designed. This refined finite-dimensional model, capable of recognizing radial vibrations, has generated the results that comply with numerical analyses and experimental data both quantitatively and qualitatively. Therefore, dynamic problems that have already been resolved may need refinement.

A lot of papers have been dedicated to simulation of dynamic processes in soil and underground structures. For example, some authors considered wave distribution in underground water pipes for creation of vibration monitoring system, others considered theoretical and algorithm aspects of efficient implementation of realistic seismic wave attenuation due to viscosity development with the help of Finite Difference Method, etc. The paper describes the numerical simulation, designed for simulation of the stress-strain state in the ground subjected to wave processes. We consider the ground with a concrete structure immersed in. The purpose of the work is the description of small vibrations in hard soil, which can nevertheless make undesirable impact on the objects in the ground or on the surface. Explicit Wilkins type scheme is used for time integration. It has proven to be successful, including the use in a well-known LS-DYNA code. As a result we created our own computer code based on the finite element method (FEM). An example of its practical usage is given.

The article represents a summarized methodology of the research into small-size pilot metal samples of restored construction facilities. In the article, the co-authors demonstrate an option that provides for the analytical identification of standard characteristic values of mechanical properties, based on initial hardness HRB and conversion of hardness values using the Brinell test. Towards this end, analytical dependence of HB hardness on HRB and HRC is proposed. The numerical identification of the temporary resistance to tensile stress σ
_в required the pre-setting of the value of the average coefficient of relative elongation. This average coefficient was employed to identify the values of relative elongation and contraction, as well as the yield value of the metal. Standard plasticity and strength values were employed to compile an equation for complex criterion C. This criterion was employed to identify the value of relative uniform elongation and transverse contraction, and both were employed to assess the resistance to tensile stress and fatigue. The optical microscopy method was used to identify the pilot sample of the metal as structural carbon steel having grade C15. Its strength analysis based on the properties of its structural components has proven the identity between the sample metal and the aforementioned steel grade. The method proposed by the co-authors helps to identify the metals of restructured construction facilities on the basis of small-size samples to avoid the collapse of metal structures.

This paper considers and asserts the need to obtain the results of inspection of a building at the stage of its commissioning in order to apply comprehensive methodology for assessing its residual life. The author proposes to build regression relationship by correlating the levels of the time series dynamics of stress at certain points of the object calculation scheme considering the results of subsequent surveys. It allows estimating the wear rate of structural elements. The assessment of the reliability and durability of the building frame in a deterministic form is based on the limit states method. The application of this method allows taking into account the random nature of not only the combination of existing loads, but also the strength properties of construction materials by creating a system of safety factors.

The co-authors consider the design solution developed for a panel residence building, type series 1-115, and provide a description of the emergency destruction of structural elements of a 9-storey panel residence building of this type (built in 1979), following a gas explosion. The overall length of the building is 86.4 m; its width is 12 m. The structural system in this building represents a longitudinal wall. Its external longitudinal walls are wade of ceramsite concrete, while its interior walls are made of concrete. Its reinforced concrete hollow slabs rest on the longitudinal load-bearing walls. The transverse walls of staircases are made of concrete blocks. The strip foundation supports the load-bearing walls of the building. The epicenter of the explosion was located in the kitchen on the eighth floor of the building. The kitchen was immediately adjacent to the staircase of the building. Partial destruction of the building followed the gas explosion. Exterior walls of its eighth and ninth floors and the attic were destroyed. Panel buildings designed in pursuance of the longitudinal structural system are more vulnerable to explosive loads compared to buildings designed to the cross-wall structural system, where bearing slabs rest on three interior walls. Thus, all slabs rest on each of the three internal walls of the building on both sides. In the buildings designed to the longitudinal wall structural system, slabs rest on the two walls, one of which is external. The article is based on the report following the inspection of the technical condition of the building, undertaken subsequent to its emergency destruction.

In the process of roads construction the necessary transport and operational characteristics should be achieved, which depend on the quality of the applied, material and technologies. Under the loads of transport means and the influence of weather conditions on the road pavement deformations and destructions occur, which lead to worsening of transport and operational characteristics, decrease of operational life of the road and they are often the reason of road accidents. According to the data of the Strategic Research Center of "Rosgosstrah" more than 20 % of road accidents in Russia occur due to bad quality of road pavement. One of the main directions in traffic security control and prolongation of operational life for road pavement of non-rigid type is road works, as a result of which defects of pavement are eliminated and in case of timely repairs of high quality the operational life of the road increases for several years. The most widely used material for non-rigid pavement repairs is hot road concrete mixes and in case of adherence to specifications they provide high quality of works. The authors investigate the problems of hot asphalt concrete mixes for repairs of road surfaces of non-rigid type. The results of the study hot asphalt concrete mix’s temperature regimes are offered in case of repair works considering the temperature delivered to the work site and the ambient temperature depending on the type of mix and class of bitumen.

In the article, the co-authors offer their advanced and efficient methodologies for the recycling of the rice straw, as well as the novel approaches to the ceramic brick quality improvement through the application of the rice straw as the combustible additive and through the formation of amorphous silica in the course of the rice straw combustion. The co-authors provide characteristics of the raw materials, production techniques used to manufacture ceramic bricks, and their basic properties in the article. The co-authors describe the simulated process of formation of amorphous silica. The process in question has two independent steps (or options): 1) rice straw combustion and ash formation outside the oven (in the oxidizing medium), and further application of ash as the additive in the process of burning clay mixtures; 2) adding pre-treated rice straw as the combustible additive into the clay mixture, and its further burning in compliance with the pre-set temperature mode. The findings have proven that the most rational pre-requisite of the rice straw application in the manufacturing of ceramic bricks consists in feeding milled straw into the clay mixture to be followed by molding, drying and burning. Brick samples are highly porous, and they also demonstrate sufficient compressive strength. The co-authors have also identified optimal values of rice straw and ash content in the mixtures under research.

The co-authors offer a new method designated for the measurement of the liquid level inside hydrostatic and hydrodynamical elevation meters. This innovative leveling method prevents any temperature influence on the measurement results in each vessel, although the temperature inside the vessels does not need to be measured. The result is reduced to the base temperature value inside each vessel. Another strength of this method consists in its insensitivity to the liquid temperature in the vessels or to the difference of temperatures. Moreover, there is no need to be aware of the function describing the temperature to density correlation, whereas the accuracy that ensures the prevention of any influence of the temperature-induced error is solely determined by the accuracy of the liquid level registration alongside the top edge of the float. Besides, the temperature range being measured is unimportant, although it must remain within the limits that assure the preservation of the water properties (to prevent boiling, freezing, etc.).

The co-authors have designated the point for the identification of the critical velocity and intensity of the hydro-abrasive wear within the framework of the two-phase flow mechanics challenges. In this article, the two-phase flow is analyzed as the flow that has the solid phase, including ore particles, concentrates and tailings, solid fuel combustion products, sand, and construction materials, etc., and as the flow containing the liquid phase, or water. The authors have identified the influence produced by the presence of fine-dispersed solid particles in the two-phase flows that transport the milled ore concentrate due to the presence of the water. Variations in critical velocity values, driven by the per-cent clay content in the ore, were exposed to the experimental research performed by the Laboratory of Hydraulic Transportation at the Hydraulics Department, MGSU. The experimental data are consistent with the findings of the analysis of the influence produced by dust fractions on the critical velocity at the Eastern site’s placer of Malyshev deposit. The co-authors offer their methodology for the refinement of the critical velocity analysis depending on varied per cent clay content values; the diagram compiled in relative coordinates, and the approximative correlation required for practical applications. The proposed methodology consisting in feeding fine-dispersed additives into the two-phase flow, reduces the critical velocity.

The article has summarized findings of the research into the stress-strained state of the concrete dam. Within the framework of this project, the co-authors have analyzed particular features accompanying field data processing, if the concrete dam serves as the data source. The co-authors have derived average linear expansion coefficients for frozen concrete samples originating from varied dam zones. The findings of numerical studies are provided with the account for the variable value of the linear expansion coefficient of the concrete exposed to negative temperatures. Specialized contact methods in finite elements simulations were employed to simulate the casting joints, with the monolith height being equal to 1.5 m, to take account of the non-linear shear strain of joints and their opening. The analysis performed by the co-authors is based on the combinations of loads and other exposures typical for January as the coldest month of an average year. Casting joints were only simulated in the bottom of the finite element dam model, while no joints were simulated for the dam top. The findings have proven, that the 1.53-fold rise in the value of α accompanying concrete freezing, influences the strain state of the dam at Bogouchanskaya hydropower plant. However no effect was produced by the change in the α value onto the strain state of the dam face. Besides, the rock-to-concrete contact depth and width increased. Although, given the small value of the aforementioned increase (decimal points of a millimeter), it will produce no effect on the filtration underway within the bedrock base of the dam. Changes in the value of the linear expansion coefficient of concrete must be taken into account when physico-mechanical characteristics of concrete are identified for the purpose of the finite element analysis.

In the article, characteristic values of dynamic sizes of bottom and suspended sediments, including their probabilistic assessment, are considered. The article presents the processing results in respect of the experimental data for bottom and suspended sediments, obtained in the laboratory environment using samples and filming methods. The experiments have proven that the dynamic hydraulic size determines the height of rise for the particles of the saltation load, rather than suspended ones. In the laboratory environment, the maximal height of rise is mainly driven by the relative flow depth. According to the assessment made by the co-authors, depths of flows employed in the experiments designated for the identification of heights of rises, were comparable to saltation heights of particles. Besides, the saltation height of particles, having relative density well below 2.65, nearly always exceeded half of the depth of the laboratory flow. Hydrodynamic conditions favourable for the separation and motion of artificial particles in coarse surface tanks are far different from the motion of sand particles on the bottom of lowland rivers. Values of hydraulic resistance ratios typical for laboratory experiments by far exceed their values typical for lowland rivers, and it means that the conditions of the experiments performed in the laboratory were similar to those typical for mountain rivers. The research findings have proven that the particle separation and motion pattern, if artificial particles are made of the materials demonstrating variable density and elasticity values and if loose particles travel over fixed ones, is different from the pattern typical for natural particles having variable coarseness.

Ropeways are an eco-friendly and economically viable transport used for transportation of passengers and shipment. Ropeways are widely applied during construction in the conditions of a mountainous relief. The state programs aimed at the development of mountain recreational centers (MRCs) stipulate ropeways construction in accordance with the MRC situational plan. Safety and comfort of a ropeway are defined not only by its technical characteristics, but also by its linking to the relief, MRC facilities and infrastructure. The article describes the main design stages of a ropeway starting from the concept, a choice of its axis, determination of capacity, type of a ropeway, requirements to the track before the design of drop-off/pick-up zones. For each design stage the explanations, which reflect real work specifics, are provided, together with the technical characteristics for calculations and solution samples. The concept defines the functional purpose of a ropeway: ski slopes/ tourist zones/ recreation areas; the season of ropeway operation, the scheme of communications with the MRC objects, the capacity of reception base, the minimum distance from the bottom stations to residential complexes. The critical decisions of axis and track design are carried out by a coalition of designer-planners, expert designers and ropeway technologists. The ropeway, which performs transport function, unites all the objects of the mountain recreational center into a single complex. The optimum placement of a ropeway deals with the questions of comfort, safety and profitability, therefore greatly contributing to the quality of the whole ropeway project. During the MRC development one should consider the questions of infrastructure expansion, year-round ropeway operation and increasing ski tracks capacity, which will demand ropeway modernization and/ or changes in the situational plan of the mountain recreational center.

The author offers an original concept designated for the generation of the model designated to simulate interaction between the enterprises comprising one major construction company within the framework of the production and logistics chain, comprising production facilities, transport enterprises, construction and assembly companies. The author has identified the factors that may produce an adverse effect on construction operations or cause untimely commissioning of a construction facility. The author employed methods of mathematics to describe the operations performed by each constituent enterprise. A graphic model describing each operation was compiled through the integration of mathematical functions. The model binds specific operations, performed by constituent companies, to deadlines, drives attention to interaction bottlenecks, and makes adjustments to assure reliable attainment of the main goal, that is, the timely commissioning of a construction facility.