At the present time reinforced concrete is the main construction material in civil and industrial construction. Cast-in-place and precast construction is gradually becoming a more widespread type of house-building, but still there is a lack of data, including experimental data, which allows evaluating the stress and strain state of a construction of a slab cast over precast joists. Experimental research of stress and strain state of slab cast over precast joists with prestressed reinforcement was carried out. An experimental model of a fragment of a hybrid precast/cast-in-place building was produced and tested (reduction scale 1:6). The experimental investigations of slab cast over precast joists with prestressed reinforcement proved that the construction solution of the framework offered in the previous works of the authors possess good stiffness, crack-resistance and bearing capacity. It well fits for constructing the slabs of long spans in residential and public buildings.

One of the main requirements to the operational integrity of reinforced concrete flexural elements is nonexeedance of the deflection limits at the assumed load. It is possible to provide the given requirement using different methods, one of which is the production of a sandwich construction of the concretes with different strength. The article presents the results of theoretical and experimental investigations of the deflection of reinforced concrete beams with the top layer made of high-quality concrete, with different percentage and strength of longitudinal tensile reinforcement without prestressing. The study of different methods of calculating the curvature of reinforced concrete beams is carried out and the recommendations on calculating the deflections of such elements are made. The use of high quality concrete in the compression area of flexural elements allows reducing the deflections. The theoretical deflections of beams produced of the B60 class concrete are 15…20 % more than the deflections of the proposed composite sections in case of equal bearing capacity. The authors proposed a formula to calculate the bending of reinforced concrete flexural members with the top layer made of high-quality concrete in the compressed area.

In this paper the authors give a solution to the problem of the impact of a rolling stock on the rail track on the basis of modeling a railway track as a multi-layered space, introducing each of the layers is a quasi-elastic orthotropic layer with cylindrical anisotropy in the polar coordinate system. The article describes wave equations, taking into account the rotational inertia of cross sectional and transverse shear strains. From the point of view of classical structural mechanics train path can be represented as a multilayer system comprising separate layers with different stiffness, lying on the foundation being the elastic-isotropic space. Winkler model provides that the basis is linearly deformable space, there are loads influencing its surface. These loads are transferred through a layered deformable half-space. This representation is used in this study as an initial approximation. For more accurate results of the deformation of a railway track because of rolling dynamic loads it is proposed to present a railway track in the form of a layered structure, where each element (assembled rails and sleepers, ballast section, the soil in the embankment, basement soils) is modeled as a planar quasi-elastic orthotropic layer with cylindrical anisotropy. The equations describing the dynamic behaviour of flat element in a polar coordinate system are hyperbolic in nature and take into account the rotational inertia of the cross sectional and the transverse shear strains. This allows identifying the impact on the final characteristics of the blade wave effects, and oscillatory processes. In order to determine the unknown functions included in the constitutive equations it is proposed to use decomposition in power series in spatial coordinate and time. In order to determine the coefficients of ray series for the required functions, it is necessary to differentiate the defining wave equations k times on time, to take their difference on the different sides of the wave surface, and apply the consistency condition for the transition from the jump of the derivative of a function in the coordinate to the jump of the derivative of a sought function in time of higher order. The proposed approach allows considering the whole structure of the railway track in the form of a set of layers, making for each layer (rail - sleeper; sleeper - ballast; ballast - ballast bed) a system of equations and solving them. Therefore it is possible to vary the characteristics of different layers and their modules of elasticity, determining the optimal thickness of the ballast layer or oversleeper and undersleeper strips.

The improvement of the structure of cement mortars on micro- and nanolevels by means of disperse reinforcement by modified microfibers promotes the considerable improvement of operational characteristics of the designs made on their basis. However, the absence of the developed technology of preparing the cement mortars reinforced by the modified microfiber providing the uniform distribution of the microfibres in volume of a composite constrains the widespread introduction of such solutions in the construction practice. The results of the researches of the technological parameters of preparing the microfiber reinforced cement mortars in the turbulent mixer are presented in article. The results of the production experiment on determining the bending durability are reflected as well as the variation coefficient of the durability of the reinforced samples prepared by means of the turbulent mixer. The results of the influence of the water-cement relation of the mortar mix and influence of the time of mixing the components in the turbulent mixer on change of mobility of the mix and strength characteristics of the hardened solution are presented. The results of the tests indicated the efficiency of preparing cement mortar reinforced by modified microfiber in the turbulent mixer. The reinforced samples are characterized by the increased bending durability and high uniformity of the strength characteristics. In case of turbulent mixing of the components of mortar mix its mobility increases from 5 to 25% in comparison with the mix prepared manually. The time of mixing the components in the turbulent mixer has an impact on the strength characteristics of the fiber reinforced solution. The optimum time of mixing the components contributes to a certain water-cement relation of the mortar mix. Therefore, the preparation of the cement mortar reinforced by the modified microfiber in the turbulent mixer is characterized by high efficiency and productivity, the strength and technical characteristics of the solution increase.

On the contemporary stage on the development and advancement of processing technologies of machine and equipment details it is necessary to find a complex solution to the problem of their performance characteristics. This solution supposes the development of specific methods providing and advancing some specific index of performance efficiency (often regardless of real coupling state) and the creation and implementation of the technologies having complex physical and technical impacts on the contact combination. The novelty of processing methods is determined by all the components of the technological system, each of which has its own novelty or creates the novelty of the system as a whole due to definite non-traditional combination of the known components. The system of improving the existing and creating new methods and technological processes of manufacturing the products is considered. The mechanical, physical and chemical effects on the work surface in case of specific kinematics of tool path and the workpieces during operation, and also the wear of engine cylinders are analyzed. The authors offer a technology of obtaining nonporous hot-stamped powder alloys with higher strength properties of the outer surface and high plastic properties of core. The unity of the processes of power, temperature and other effects on the working surface of details during their manufacture and operation is established.

In this paper the authors consider the possibility and provide specific solutions to create the automated system of track maintenance on the example of automation of technological operations to restore the equal elasticity of the undersleeper foundation. The relevance of the work stems from the fact that the modern and perspective requirements to the track maintenance in the conditions of the transition to high-speed, high-speed, high-tonnage traffic can be implemented only by switching to a new system of track maintenance based on the performance of work of specialized high-performance machines and on the new system with maximum opportunity for automation technology. More than half of the volume of works on the current maintenance of the tracks are the works on the removal of splashes, straightening and tamping of track, the technology of which can be divided into two components: calculation-evaluation and the generation of control actions on the railway track. Track machines are used extensively at the local bearing places of the occurrence of splashes on track sections or for continuous bearing plot ways to restore the equal elasticity of the undersleeper base and reduce the degree of non-uniformity deviations in rails’ position on level and in plan, as well as track subsidence. The bunker for filling the ballast may be mounted on additional frame or on offset brackets of the machine. The device for measuring the position of a railway track includes the means for measuring the deflections of the road, bending rise the track in the longitudinal profile and the position of the track on level (elevation of one rail in relation to another) and the adjacent block determining the actual position of a railway track in plan, in longitudinal profile and on level. The block of determining the amount of ballast consists of interconnected devices for determining the value of shifts and raise of the track and the block of comparing the track raise values with determining the amount necessary for filling of ballast. A device for determining the magnitudes of the shifts and the track raise consists of the interconnected unit for comparing the actual position of the track with a given (estimated) position of the track and a block determining the values of the track shifts and raise, which also provides the conversion of the recorded deflections of the track in the longitudinal profile in the track subsidence. The block comparing the track raise values with determining the amount necessary for filling the ballast, compares the magnitude of the track raise, determines changes in the transverse area of a prism in case of track raise and determines the amount needed for ballast filling. It also controls the control unit of the device for filling the ballast. The authors developed and tested the schemes of using the elements of technological processes automation during the operation of hopper dispenser with the track surfacing, which will allow reducing the duration of track possessions and will speed up the track maintenance.

Creating an effective insulation envelope of the building is possible only using high-quality materials, preserving their characteristics both in the early stages of operation, and for the whole billing period. It is an important opportunity to assess the thermal insulation properties and predict its changes over time directly in the conditions of the construction site. The products based on mineral fibers (rock and glass wool, basalt fiber) are the most widely used type of insulating materials in the domestic construction. Therefore, the operational stability valuation methods must be primarily created for this group of products. The methodology for assessing the thermal insulation properties includes two main components: testing equipment and methodology for assessing the operational stability. The authors tested the methodology of the accelerated testing and prediction of durability for mineral wool products of laminated, corrugated and volume-oriented structures. The test results give good convergence with the methods recommended by the building regulations. Application of thermal insulation materials are an effective way to form the thermal envelope of the building, reducing energy costs and increasing the durability of building structures. The material properties are determined by their structure, which is formed during the technological impacts.

The use of thermal insulation materials is an effective method to create an insulating envelope of a building, as well as to reduce energy costs and increase the durability of building structures. The properties of stone wool products and their operational durability is largely determined by the conditions of formation of the mineral wool carpet, uniform distribution of binder and its curing and the heat treatment conditions. Most domestic technologies are aimed at the production of mineral wool products with volume-oriented structure, which is formed using special units: spreader and corrugator placed in a production line. The next step to obtain the optimum structures is the production of dual density slabs. The denser upper layer receives mechanical loads caused by the operating conditions; the lower, less dense, but more thick layer performs the main function - insulation. The dual density slabs are produced on standard lines supplemented with a special unit, which is located in front of the heat treatment camera. Optimization of heat treatment parameters and prediction of the properties of materials is performed using software package.

The article states that the use of spoil heaps (coal mining waste) in the production of structural ceramics is expedient. It shows the reduction of negative ecological effects during the life cycle when coal mining waste is used in the initial blend for the production of structural ceramics. It shows that the development of the recommendations for the use of coal mining waste in the production of structural ceramics is an urgent issue as far as the use of coal mining waste in the production of structural ceramics can lead both to the achievement of resource saving and positive ecological effect and to the undesirable decrease of the basic physical and mechanical properties of the final products when the structure of the mix is inappropriate. In order to develop these recommendations the authors have examined the microstructure, mineral composition and physical and mechanical properties of structural ceramics produced with the use of coal mining waste, which effect the consumer properties of the target material. As a result of the research the authors have made the conclusions about the nature and degree of impact of coal mining waste quantity on the physical and mechanical properties of construction ceramics. The comparison of the data received during the measurement of the basic physical and mechanical properties of construction ceramics with the results of the research of microstructure, elemental and mineral composition of the samples has shown their correlation.

At the stage of organizational preparation of the concentrated construction the main objective is the formation of the expected directions of territorial development. The result of the information output of this stage is geoinformation data, i.e. regulatory references on the territories of different function: industrial, civil, social, transport schemes, etc.. It is necessary to emphasize that the methodological basis for complex preparation of separate building sites, residential estates in the form of residential districts and buildings of this type of concentrated construction, has already been rather fully stated in the works of many scientists. At the same time such features of the concentrated construction are subject to the research and systematization as: the variety of the types of construction models of multi-purpose objects; preference of various cluster territories in the volumes and terms of investment; combination of separate stages of organizational preparation for the purpose of delivery of the sites within the planned terms of the beginning and the end of construction. The advantage of territorial cluster economy is in the fact that payback periods of infrastructure facilities are much less, than, for example, in case of infill construction. Besides, in case of cluster construction the investment of the preparatory period and the construction period are carried out from different sources and this type allows investors invite not only the state and municipal sources, but also the means of individuals. For effective work of a complex method of the organization of cluster building it is necessary to optimize schedules of investment streams and to lead them to an optimum look. Thus, the effective work of a complex method of a territorial cluster construction requires close cooperation of the participants with each other, with investors, government bodies, banks, consulting organizations, scientific research and educational institutions for further introduction and development of cluster construction. Effective organizational preparation of cluster construction will allow beginning and bringing into operation the cluster objects in due time.

RECONSTRUCTION IN A CITY The demand in comfortable housing has always been very high. The building density is not the same in different regions and sometimes there is no land for new housing construction, especially in the central regions of cities. Moreover, in many cities cultural and historical centers remain, which create the historical appearance of the city, that’s why new construction is impossible in these regions. Though taking into account the depreciation and obsolescence, the operation life of many buildings come to an end, they fall into disrepair. In these cases there arises a question on the reconstruction of the existing residential, public and industrial buildings. The aim of the reconstruction is bringing the existing worn-out building stock into correspondence with technical, social and sanitary requirements and living standards and conditions. The authors consider the currency and reasons for reconstruction of residential buildings. They attempt to answer the question, what is more economical efficient: new construction or reconstruction of residential buildings. The article offers a method to calculate the efficiency of residential buildings reconstruction.

In the article the kinds of the concentrated construction are considered, which differ by types of construction production with account of branch and regional estimate factors. The methods of assessing the level of preparation of the territories taking into account different types of models and the purposes of regional planning are given. Despite the approved postulates, which are available in the theory and practice of organizational preparation of the territories, many questions still have not been solved and are handled using ineffective methods. The authors believe, that during preparation of territories it is necessary to introduce the elements of cycles’ combination of engineering calculations and laying design of communications to a building site. Defining the sequence of these works’ performance for objects is modelled taking into account the cyclic-combined method of preparing the sites for construction. The development of the territory can be provided only in case of annual investment into various objects of cluster construction, in order to uniformly or rhythmically load the construction capacities upon condition of the rhythmical preparation level of the territories of concentrated construction. As the generalizing indicator the criterion of rhythm of means planning can be used. Thus, using a rhythm indicator as a criterion of organizational preparation of territorial clusters it is possible to provide the necessary level of investment of preparation and construction programs for a certain period.

The article focuses on clarifying the content characteristics of the methodological requirements to factorial analysis performance. The author associates its changes with consideration of the analysis of inter-regional, multi-sectoral and foreign-economic contexts of development in the logic, with the assessment of variability of external and internal environment, with the need to localize the factor impact in time. The valid analysis is also impossible without account for the interaction of external and internal factors distributed according to the spheres of influence: the production sphere and the sphere of consumption. This will enable to create a long-term advantage of all the structural elements of the national economy. The increasing importance of the construction in the structuring of living environment increases the importance of institutional factors and of the assessment of responsibility degree of all the hierarchical elements of the construction industry.