The author discusses the problem of consistency between the existing architectural environment and new architectural planning solutions in the south-western part of the Yerevan city centre.The article is based on the analysis and systematization of spatial planning, architectural, design, historical, and literary sources covering Yerevan and its architecture. Business districts of urban centres are also taken into account.The author analyzes the features of formation and development of the centre of Yerevan and interrelation between planning solutions and concepts at different stages of its master plan development. A detailed analysis of spatial planning solutions applicable to the south-western part of the city center as a territory full of cultural and historical landmarks is provided in the article.This area has the size of dozens of square kilometers, and it is composed of the main urban design dominants, such as the historical nucleus with the ensembles of citywide importance and monuments of the so-called Tamanian period, the Republic square, lake Yerevan, and Paskevich hill.Numerous historical settlements, such as the Urartian fortress, Karmir Blur, Shengavit, Yerevan fortress, old Nork and others are situated here. The area has historical gardens (Dalma, Sardur gardens), beautiful panoramic view sites as the best viewpoints for the visual perception of Ararat mountain, and natural landscapes.The importance of consistency of spatial planning policies of the urban development documentation such as the Master plan of Yerevan is emphasized. The analysis and substantiation of the value of the area is considered. Research-backed proposals are provided in terms of the optimization of architectural planning solutions.

The article deals with the methods of restoration of large buildings of Orthodox churches in Russia. Practical solutions, described in the article, are applicable to the majority of church buildings partly demolished or rearranged during the Soviet era. The authors describe the restoration works performed at the convent of Martha and Mary as a good example of this practice. The article is focused on the general issues that complicate the restoration process, including lack of any uniform restoration solutions, lack of global cultural legacy protection programs, and the poor technical condition of restored buildings.The authors provide an overview of the restoration project that involved restoration and renovation of the New Jerusalem monastery building and Znamenskaya church building in Kholmy village. The solution was to have several subcontractors involved into the design and construction process. Department of reconstruction and structural inspection (ORZS) of Moscow State University of Civil Engineering (MGSU) was responsible for the supervision over the process of restoration and the work quality control. This article highlights the growing demand for the restoration control, especially if versatile assignments associated with foundations, structural, mechanical and finishing works are performed by different contractors. Special attention is driven to advanced waterproofing solutions applicable to underground structures, as leaks damage unique wall paintings. The authors raise the issues of research into the international experience of reconstruction and restoration of architectural monuments, methods of boosting religious tourism and respect for the history of Russia.

Standard metal ductility factors are elongation and necking. These factors are defined as conditional ones in contrast to true (logarithmic) ductility factors. In addition, elongation and necking do not appear in an explicit form in the design formulas for the determination of static, cyclic or dynamic strength values.At the same time, exact values of ductility factors should be integrated into com-bined workability criteria for steels and alloys together with strength factors due to the unity of the processes of deformation and resistance to deformation. This combination of ductility factors and strength factors appears in a well-known formula describing dependence between the ultimate breaking strength and hardness.Here, the proportionality factor is equal to 0.3–0.6, and it is not characterized by the corresponding values of elongation or necking. Hence, the intention is to express the above-mentioned proportionality factor in a different form in respect of ductility characteristics, and, as a result, new ductility factors are proposed.Dependencies between ductility factors and yield limits, identified by the co-authors, may be applied to identify the synergetic criteria of metal materials to be used in the process of design, production and operation of welded metal structures. Moreover, the findings of the co-authors may be used in the process of design, production and operation of working elements of construction machines and equipment.

Today, an enormous number of research papers by foreign and domestic authors cover the research into vibration of plates. Despite this variety, oscillation of transversely isotropic plates remains understudied. The most substantial contribution into this area of research was made by S.A. Ambartsumyan, V.V. Bolotin, E.J. Brunelle, and M. Levinson. The author provides the summary of a frequency equation describing self-excited oscillations of a transversely isotropic plate resting on the strain foundation, if one edge of the plate is rigidly fixed and the other three edges are hinged. The problem was solved using the approximate method employed to derive the frequency equation needed to identify self-excited oscillations of the plate. The formulas, derived by the author and designated for the identification of frequencies of free transverse vibrations of the plate, are suitable for practical application; they may be applied for the identification of the nature of dependence between natural frequencies of the plate and its geometry.

Steel rib-reinforced beams are frequently used in the reconstruction of architectural monuments as a replacement for timber slabs. Insufficient amount of information about the stress-strain state of composite steel and concrete slabs limits their use in the domestic construction practice. The author describes the composition and geometric parameters of the structural solution. The author provides illustrations representing the reinforcement slab and anchors needed to track the behavior of composite concrete floors, the photographs featuring the voltage sensors attached to the shelves and the wall of a steel beam, the instrument used to measure the relative strain in the bottom of the beam. The technique employed by the author is used to track the dynamics of strains in the fiber discs, steel beams, and development of deflections. The author also describes the nature of stress on the top of the beam section. The experimental research has confirmed the assumption that the concrete setting time influences the stress-strain state of the steel beams as the basic elements of composite load-bearing floors. The author also provides the findings of the pilot studies.

The major territory of Siberia is occupied by underexplored, hardly accessible areas having unstable or frozen soils. Development of these territories is hampered for a number of reasons, including poor weather and soil conditions, lack of infrastructure, roads, networks, and remoteness from industrial enterprises. Traditional building methods are rather expensive. The latter circumstance calls for new types of residential and public buildings, with the main requirement being their transportability (by air and land transport), higher degree of prefabrication (including foundations), light weight of structures, fast assembly, possibility of assembly and installation of large components without the use of heavy machinery, application of local materials, structural reliability, especially in the conditions of unstable soils. Construction operations on permafrost soils are not to alter the soil properties.The proposed structure of low-rise buildings is aimed at the attainment of the followings objectives: assimilation of hardly accessible areas of Siberia, development of low-rise housing, and secondary use of veneer waste products.A prefabricated building of the closed type consists of a foundation plate, as well as walls and coverings arranged in the form of a spatial framework united into a single manifold system. Beam elements of a prefabricated building are to be made of timber-based materials and assembled into a single bolted mountable and dismountable structure by means of a system of shaped metal node elements.Advantages of new low-rise buildings include their higher transportability due to the compactness of individual items and reduction of the overall weight, smaller construction term; increase in the building reliability on weak, unstable and frozen soils; expansion of the area of architectural design; development of a new method of recycling of large-size veneer waste products. The above features can make the new type of low-rise buildings highly competitive.

The authors present features of the strength analysis of monolithic beamless floors, obtained using the limit equilibrium method. This method consists in the following procedure: a monolithic plate bends and breaks in the limit equilibrium under a uniformly distributed load. The influence of various combinations and dimensions of column sections on bending moments are considered. The influence of cross-sectional dimensions of columns on values of effective forces is analyzed in detail. The general equation to solve the strength problems of monolithic plates, having regular grids of columns exposed to continuous uniform loads, is derived and solved by the authors. This expression can be applied to calculate the span and support moments and to establish optimal reinforcement of plates. Results of calculations are presented in graphs that make it possible to derive interesting findings.

Application of accelerograms to the analysis of structures, exposed to seismic loads, and generation of synthetic accelerograms may only be implemented if their varied characteristics are available. The wavelet analysis may serve as a method for identification of the above characteristics. The wavelet analysis is an effective tool for identification of versatile regularities of signals. Wavelets can be used to detect inflection points, extremes, etc. Also, wavelets can be used to filter signals.The authors discuss particular theoretical principles of the wavelet analysis and the multiresolution analysis. The authors present formulas designated for the practical application. The authors implemented a wavelet transform in respect of a specific accelerogram.The recording of the horizontal component (N00E) of the Spitak earthquake (Armenia, 1988) was exposed to the analysis as an accelerogram. An accelerogram was considered as a non-stationary random process in the course of its decomposition into the envelope and the non-stationary part. This non-stationary random process was presented as a multiplication envelope of a stationary random process. Parameters of exposure of a construction site to the seismic impact can be used to synthesize accelerograms.

The authors consider a dynamic problem solving procedure based on the theory of elasticity in the Cartesian coordinate system. This method consists in the development of the pattern of numerical solutions to dynamic elastic problems within any coordinate system and, in particular, in the polar coordinate system. Numerical solutions of dynamic problems within the theory of elasticity are the most accurate ones, if the boundaries of the areas under consideration coincide with the coordinate lines of the selected coordinate system.The first order linear system of differential equations is converted into an implicit difference scheme. The implicit scheme is transformed into the explicit method of numerical solutions. Using the Galerkin method, the authors obtain formulas for the calculation of both the points of the computational domain and the boundary points.Difference ratios similar to those obtained for a discrete rectangular grid and derived in this paper are suitable to design any geometry, which fact significantly increases the value of the methods considered in this paper.As a test case, the problem of diffraction of a longitudinal wave in a circular cavity, where maximum stresses are obtained analytically, was considered by the authors. The proposed method demonstrated sufficient accuracy of calculations and convergence of numerical solutions, depending on the size of discrete steps. The problem of diffraction of longitudinal waves in a circular cavity was taken for example; however, the proposed method is applicable to any problems within any computational domain.The polar coordinate system is the best one for any research into the diffraction of plane longitudinal waves in a circular cavity, since the boundaries of the computational domain coincide with the coordinate lines of the selected system.

The authors examine the impact of dynamic loads produced on the strength and deformability properties of concretes and their micro-cracking. The experiment performed and analyzed by the authors consisted in the dynamic loading of a concrete sample that caused its destruction. The analysis of the experimental findings consisted in the identification of specific conditions of cracking, derivation of dependencies and compilation of charts. The following conclusions are made in furtherance of the authors’ analysis of the experiment in question:1) experimental findings help identify the nature of influence of the stress state on the strength value, deformability and micro-cracking of concretes. For example, it is discovered in the process of the experiments that the lower bound of the microracking dynamics increases more significantly than the prism strength.2) Regularities of influence of the rise in the loading intensity produced on concrete deformation properties are identified. The key factor of the concrete destruction is not the nature of the deformation, but the value of the overall strain.

The article represents an overview and analysis of trenchless technologies used to provide for the leak resistance and strength of dilapidated sections of pipelines made of ceramics, cast iron, asbestos cement and other materials. Sectional pipeline repair technologies, considered by the authors, include those for the repair of loose joints of straight sections of pipelines and loose joints in the points of connection to secondary pipelines. Technologies analyzed by the authors also include those applied for the restoration of pipe shell cracks. Organic resins and bandages are to be used as repair materials.Besides, the authors provide detailed descriptions of the composition and properties of pumping resins injected into pipe cracks to restore the structural strength of pipelines and to assure their further reliable operation.Moreover, the authors assess the basic strengths of the bandage technology, including its low cost, low time consumption, and suitability to various types of pipeline damages (depressurization of joints, cracks, leaks, etc.). Besides, this method does not require any excavations, trenches, hoists or other machines.In particular, sections of underground pipelines, having diameters of 150 – 180 mm, may be repaired by specialized repair robots. Robots may be equipped with special-purpose devices, including cutter heads, bandage application heads, and color motion cameras. Besides, sectional repair of pipelines, having the diameter of up to 600 mm, may be performed using robots produced by Hachler Umwelttechnik, which are particularly efficient if the repair work is needed to be performed in the points of pipeline branching.The choice of specific pipeline repair methods and substantiation of their application are mainly driven by (1) the post-cleaning condition of a pipeline, (2) the findings of the telediagnostics, (3) options for arrangement and use of specialized machinery on location, and (4) feasibility of the pipeline operation in the course of repair works and procedures.

The authors consider particular methods, technologies and organizational aspects that may be implemented in the construction and renovation of pipelines using polythene materials instead of metals due to their economic and practical efficiency. It is noteworthy that the corrosion problem of steel pipelines is the phenomenon of metal destruction that reduces the throughput of pipelines and facilitates obstructions, juncture cleavages and water leaks as a result of reduction of service lives of pipelines. The authors analyzed the efficiency of polythene pipes from the viewpoint of hydraulic processes and the economic expediency; the authors identified that the polythene pipe’s throughput is 3 times as much as the one of steel pipes. Also, the authors determined the economic efficiency of polythene pipes: USD 0.5 million per 1 kilometer of pipeline.The authors take account of the technology-related aspect, as the water pipeline construction and reconstruction processes are limited by dense urban environments or due to the absence of overhaul factories in the close proximity to pipelines. Therefore, the results of the analysis evidence the efficiency of application of polythene in construction and reconstruction of pipeline engineering systems. It is highly resistant to abrasion and corrosion; it boosts the water flow velocity due to the low rough-ness of the internal surface; its service life is long enough, and its transportation is problem-free.

The authors present a fairly extensive analysis of the state of the cereal crop industry in the Republic of Tajikistan and other regions of East and South-East Asia. Problems of generation of a huge amount of waste in the course of processing of cereals, in particular, rice straw processing by-products, are raised by the authors. The authors propose their original solution to the problems in question. Besides, traditional and original methods of application of rice straw in low-rise construction and production of building materials are presented in the article. The major part of the article covers traditional methods of disposal of rice straw as a raw material used in the production of cellulose, lignin biodegradable plastic, paper, cardboard, wicker products, thermal energy, etc. Another important issue, covered in the article, is the study of the straw/husk burning process, as well as the possibility of generating ash that contains various forms of silica. The fact that the ash content of the straw, according to various sources, varies within the range of16–20 %, and its silica content may be up to 89–91 % make it possible for the authors to state that straw and husk ash can be used as an active mineral additive in the production of effective building materials. It is noteworthy that the problems raised in the article are relevant, and their practical solutions are feasible.

One of the uses of organosilicon compounds (OSCs) is associated with the production of hydrophobic coatings for building materials. Water-proofing properties of hydrophobic coatings extend the service life and improve the performance properties of building materials. Some of OSCs form hydrophobic polymer films on the surface of various building materials. High stability of these coatings is associated with the possible existence of chemical bonds between the polyorganosiloxane film and the hydrophilic surface of the material. Presently, there is no clear understanding of the mechanism of interaction between the mineral substrate and the film, although OSCs are widely used as part of water-proof building materials.Towards this end, the authors have identified the conditions that facilitate the formation of protective coatings on the surface of mineral substrates, if OSCs are applied to the surface of building materials. The authors have completed a research into the nature of interaction between the coatings and the mineral substrate to determine their physical and chemical properties. The silylation of calcium hydroxide by diethyldichloro-, ethyltrichlorosilanes was studied as the model process. The products of silylation were studied using methods of gas-liquid chromatography, infrared spectroscopy, electron mi- croscopy, X-ray diffraction and differential thermal analysis.The authors used the method of gas-liquid chromatography to discover that the periods of fast and slow conversion of silanes corresponded to the periods of domination of hydrolysis or hemosorbtion. The authors discovered that the hydrolysis products of diethyldichloro-, ethyltrichlorosilanes do not react with calcium hydroxide.The authors used the method of the thermal analysis to discover the physical and chemical properties of oligomers and polymers formed on the surface of the mineral substrate. Comparison of the findings of the thermal analysis of poliethylpolysiloxane in the mixture and in the block (312 °С) shows that there is practically no shift of the maximum exotherm. The following components of the hydrophobic effect of silylation where identified: formation of insoluble polyorganosiloxanes on the surface and inside the mineral stone accompanied by partial hemosorbtion, and physical adsorption of monomers, oligomers and polyorganosiloxanes - hydrolyzates on the mineral stone surface.

The author presents the prospects for the use of a magnetic separator, equipped with a filter matrix, in the treatment of ceramic suspensions and minerals. Particles of ferromagnetic impurities are captured by matrix pores, when purified media is transmitted through the magnetized filter matrix. The particle capture efficiency depends on the level of the filter matrix magnetization. The intensity of demagnetization influences the filter matrix magnetization intensity. Unfortunately, many researchers frequently ignore the demagnetization factor of a filter matrix as a specific (granulated) magnet.The effect of self-demagnetization is studied in terms of homogeneous (solid) magnets. The effect of self-demagnetization means that poles emerge on the borders of magnetized “short” magnets. Thus, a strong inner demagnetization field emerges. The main parameter of this physical characteristic of sample-magnets is the coefficient of demagnetization, which relates the intensity of the demagnetization field and the magnetization intensity of a sample body. The author considers the relevant issue of influence of the demagnetization intensity on the average values of the magnetic permeability of porous (quasi-solid) magnets, for example, a filter matrix. This dependence is relevant for the calculation of magnetic permeability values.

The article presents the findings of the experimental studies of mechanical regeneration of the immobilized load using an electromechanical unbalanced vibrator. The sedimentation of the sludge on the synthetic load inside the physical model of a vertical bioreactor is studied. Mechanical regeneration of the immobilized sludge on the brush is proposed. The nature of dependence between the concentration of free-floating sludge and the deposition time following the mechanical regeneration is identified. The kinetics of the sludge deposition, the dose and intensity of aeration is studied, if the electric vibrator is used for the mechanical regeneration of the brush load. Thus, the application of the plane model of a bioreactor helped to determine that, if the water-sludge mixture has a small concentration of the free-floating sludge, the sedimentation is about 10 % of the total dose 30 seconds after the mechanical regeneration of the brush load. The effectiveness of the mechanical regeneration performed with the help of an electromechanical unbalanced vibrator was approximately 84–90 %. The application of the bioreactor having a synthetic brush load mechanism increases the concentration of the coagulated activated sludge.

The authors consider varied engineering actions aimed at the protection of pipelines from developing erosion processes with a focus on the conditions of northern regions. Engineering solutions, considered in the article, include prevention of erosion processes along pipelines, protection from suffusion, protection of extended areas having the limit value of the slope angle, and actions aimed at the drainage of areas along pipelines. Prevention of erosion processes along pipelines consists in the restoration of the fertile layer using biological methods, as well as the volumetric soil reinforcement using geological grids. Prevention of suffusion processes consists in the employment of various types of suffusion shields accompanied by the application of geotextile. Berms are constructed as suffusion prevention actions in extended areas having a limit value of the slope angle. This action is used to reduce the water flow energy of drainage ditches and trays along the pipeline. The authors believe that a complete geotechnical monitoring network must be designed and developed to monitor the condition of pipelines and foundation soils.

Comfort inside buildings is dependent on temperature, humidity and other parameters. Usually the higher the temperature and humidity, the more people feel discomfort. However, if the internal relative humidity is low, the inhabitant also feels uncomfortable as a result. Headache, eye irritation, sore throat and dry skin are the symptoms of these dry conditions. Dry air reduces natural protection from bacteria, infections, and makes people vulnerable to attacks of viruses and other micro-organisms. In addition to the problems associated with low humidity, excessively high humidity can also cause problems. The optimal level of humidity in the room contributes significantly to the comfortable environment. Chill may be perceived differently at the same temperature with different values of air humidity in the room. Comfort is determined by the ratio of room temperature to humidity. The temperature perceived inside and dependent on the moisture content, is measured by the Humidex index.European regulations define a desirable range of relative humidity and comfort. The humidity-dependent zone of comfort rests within this range. High temperatures are less tolerable in the high humidity environment. Modeling results obtained before and after the renovation and modernization of a five-story residential building (105 series) in Khujand, Tajikistan, helped to define the ideal parameters of relative humidity and comfort. The author proposes an ideal ratio of relative humidity to comfort and demonstrates that the optimum humidity and temperature values contribute significantly to the comfort of a person in the hot, dry climate of Central Asia.

The authors argue that the attention of designers of concrete dams shall be focused on the concrete dam — rock foundation contact zone. The study of the exposure to the rock mass tensile strength in case of the concrete dam sliding is a relevant problem; its resolution may improve the operation of the whole hydraulic engineering structure. The method of selecting the dam safety criteria based on the field test data and laboratory reservoir impoundment observations is a relevant topic for discussion. If the strength margin value is in place, Russian regulations permit the tensile strength break along the concrete - rock contact line.The team led by Yu. A. Fishman and S.Yu. Roza has for a long time been researching into the problem of the limit state of rock foundations of concrete gravity dams. The study of the rock foundation failure, if exposed to horizontal and vertical loads, was also performed by VNIIG (Vedeneev All-Russian Scientific Research Institute of Hydraulic Engineering) and MGSU (Moscow State University of Civil Engineering). Both institutions have discovered that particular attention should be paid to the methodology of identification of shear strength parameters for the analysis of the first limit state to assess the reliability of the concrete dam foundation.The construction of Boguchany HPP plant is close to completion in the KrasnoyarskTerritory. The initial impoundment of the Boguchany reservoir was commenced in April,2012. According to the rock foundation monitoring data, it can be assumed that the behavior of the contact zone exposed to the shear load is in compliance with the pre-set parameters, and it needs further studies to accompany the water level rise. The foundation monitoring data collected in the course of the experiment will let the authors study the behavior of the Boguchany dam to verify the behavior of the dam-rock contact zone exposed to the real conditions of the reservoir impoundment.In the future, the results of these studies will make it possible to establish more precise criteria for the concrete-rock contact zone of the Boguchany dam project.

The software package developed by Department of Technology of Finishing and Insulation Materials of Moscow State University of Civil Engineering is designated to improve the performance efficiency of experiments that consist in planning, implementation, and processing of findings of research projects, including solutions for their optimization. The software package assists researchers in planning and analyzing experimental findings that are influenced by versatile factors, especially if their number is different. The number of factors of impact may be set at 15, 30, 45, and 60. This software was tested in the context of the aerated concrete technology. The first stage of the research consists in the preparation for an experiment with account for all factors characterizing the manufacturing process. The software assesses the relevance of the above factors and ranks them on the basis of their significance. As a result, three groups of factors are identified: factors of major significance (Group A), factors of secondary significance (Group B) and other factors.The software package was applied in the context of the aerated concrete technology to determine the most important parameters of its production. As a result of the experiment, the group of most significant factors (group A) included foaming agent efficiency, foaming agent consumption rate, and mould filling degree, while less important factors (Group B) included modifier consumption rate, mixture temperature, exposure time and water consumption rate.

The author explores the main principles of modeling the energy performance of residential buildings using WUFI®plus software. The author also assesses and analyzes images generated using WUFI+ software within the framework of the simulation of energy parameters of residential buildings. The article also has an experimental analysis of expensive and time-consuming factors that can be avoided thanks to the WUFI®plus software which allows for (1) easy and quick changes in the structure and its design, (2) input of different boundary conditions as well as (3) various values of parameters like material characteristics.

Adaptation means accommodation of a living organism to constantly changing conditions external and internal environments. This capacity was developed in the process of the evolutionary development. Absent of this capacity, no human organism can leave normally or adjust to various external factors.In the contemporary research literature, adaptation is associated with different factors, including occupation, climate, social environment, etc. The process of adaptation is complex, and it contemplates different types of adaptation, namely, individual sociopsychological, communicative, and physiological adaptation. It is accompanied by substantial intellectual, mental and physical efforts.The variety of building structures coupled with process-related and organizational methods of their construction require attention to the issues of safety. In the course of life and work (working environment), a person is exposed to various hazards or phenomena, processes, and objects capable of damaging human health under certain conditions. An occupational hazard means an adverse impact on human health in the form of its deterioration or injury under certain conditions.The studies show that the three-shift working activity is the cause of fatigue. Fatigue boosts errors in the sensomotor coordination and deteriorates human health. The daily rhythm of physiological functions is driven by the intensity of the working activity causing changes in the body temperature, heart rate and blood pressure. Harmful factors, such as chlorine and chlorine dioxide, produce negative impact on the psycho-physiological status of the organism. They are countered by the system of adaptation and rehabilitation as an integral part of the university curriculum. Its objective is to enhance the effectiveness of professional activities, to ensure the optimal functioning of a human body exposed to heavy workloads and adverse external conditions.