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Annotaion. The relevance of carrying out research works on improving the regulatory and methodological base in the development of promising railroad rolling stock structures with the use of new structural materials with nonlinear properties during deformation (physical nonlinearity) is substantiated in the work. The possibility of using the finite element method (FEM) procedure for creating such constructions is considered. Dependence of stresses on deformations is approximated by a cubic parabola. This made it possible to obtain generalizations of the well-known relations and algorithms of the classical theory of FEM with a nonlinear relationship between stresses and deformations. The proposed technique was tested in the evaluation of the stress-strain state (SSS) of an aluminum gondola car under various standard loads according to the 1st design mode. The effect of physical nonlinearity on the SSS of a spiral beam of a freight gondola car of aluminum alloy AMg6 was estimated. The calculation of the stresses generated by the action of a longitudinal force with eccentricity shows that the stresses in the nonlinear approximation are 13% lower than the corresponding stress values obtained by calculation in the linear theory. The results obtained can be recommended for the development of pilot projects of new structures optimized for weight and strength characteristics.

The paper is devoted to the calculation of the electrical quantities distribution in the system of three conductors. The first conductor is located on the surface of a uniform soil and the other two conductors are located at depths of h and h . As result, analytic expressions of current, potential and leakage current density in the first underground construction with considering the influence of the second construction was obtained. The influence of second construction increases the value of electrical quantities in the underground construction. The analytic expressions were obtained using Fourier transform method. The analysis showed the influence of the leakage current and insulation resistance of the second construction on the electric quantities distribution in the first construction

Shotcrete lining is one of the most common types of temporary supports in tunnel construction. The influence of shotcrete lining on design calculations of permanent lining is difficult, because there is no method of designing at the present time. This leads to increasing in consumption of materials and labour of construction. The information about the influence of the basic mechanical properties of soils, geometrical size of construction per value of temporary shotcrete lining factor was obtained during research. These data formed the basis for futher development method of designing. Empirical correlations of stress distribution between temporary shotcrete lining and permanent monolithic reinforced concrete lining were obtained during theoretical research. Results of experimental research tensity of temporary shotcrete and permanent lining confirmed the possibility of using in the designing this empirical correlations. Using in the designing proposed empirical correlations will leads to reduction in consumption of materials and labour of construction.

The main engineering problem associated with the degradation of permafrost and cyclic freezing-thawing of seasonal permafrost soils is a decrease in the bearing capacity of engineering structures due to the degradation of the main physical-mechanical properties of the embankment soils. The cyclical change in temperature leads to regular freezing-thawing of the soil, as a result of which such types of deformations occur as heaving during freezing and settlement during thawing. The purpose of this work is to highlight new information about complex measures to stabilize the subgrade of railways and highways in the cold regions of China. The paper considers such measures as thermosiphon stabilization, rock fill, installation of ventilation pipes and laying of thermal insulation boards. This paper also describes the disadvantages of existing measures for stabilizing the temperature regime of the embankment and its base. Considered the main transport network of the Qinghai-Tibet plateau, including the Qinghai-Tibet railway and four highways. The experimental section of the Wushu-Xining expressway on the Qinghai-Tibet plateau was chosen as the object of the study of numerical modeling; a numerical calculation of the temperature and moisture content fields of the typical embankment was carried out, as well as numerical calculation of the embankment with rock fill for the 10th year of operation. The calculations were carried out on the basis of the «Freeze-Cold» software package specially developed for engineering calculations of the freezing and thawing process in soils. The calculation showed that rock fill allows to reduce the area of the soil thawing, raising the front of frozen soil, helps to reduce the degradation of frozen soil, which ultimately has a positive effect on the bearing capacity of the entire engineering structure. Analysis of the collected data and calculated values allows to conclude that the use of rock fill of 0,8 meters depth as an insulating material to maintain the stability of the thermal regime of the embankment on frozen ground in the considered region of the Qinghai-Tibet Plateau.

The authors propose a model of justification of the duration of the operation liner-tamping-straightening and construction machinery. Using this model, we can evaluate the efficiency and reliability of machines on any object. This allows you to most reliably predict the timing of production of certain types of works and their cost at the design stage. The article presents the indicators of full-scale tests and the estimation of reliability of manufacturing operations. One of the main factors of reliability of work of construction machines is the utilization of their time. All normative documents are obsolete data on the utilization of machines during the working time, which need updating, as the machines are constantly improving. To assess the reliability of working machines, the authors developed a database of the results of field tests liner-tamping-straightening machines, cranes, excavators, bulldozers, pipe layers, drilling rigs and dredges. To prove the validity of database values according to the results of full-scale tests were carried out two stages of verification: logical and mathematical. After sampling in accordance with GOST R 8.736-2011 was verified that it belongs to the law of normal distribution using the criterion of Pearson agreement. It was further calculated the reliability and risk of the planned volume of work in scheduled period of time. When it was considered the utilization ratio of machines time and the risk of deviation from the mean. The proposed approach to the assessment of duration of liner-tamping-straightening and construction machinery can be extended to any type of equipment and will allow to obtain numerical values for evaluating the reliability of production work in the scheduled time, which is very important in the construction, repair and maintenance.

In article methods of valuation electrical parameters and mathematical models of electic processes of reinforced concrete construction are considered. The conclusion that influence of reinforced mesh was not taken into account in describe models had been done. Method for prediction of reinforced concrete foundation which based on equation system of electric field in conductors and finite element method and allowed explicit geometry of object include reinforced mesh was suggested by authors. Authors done the assumption about invariability of potential of reinforced mesh which covered of concrete layer for direct current and alternating current due to ratio of steel and concrete resistance. Realization of nethod was done by dint of software complex Comsol Multiphysics. Research object was reinforced steel foundation TSS-4, which is located in ground. Result of research was represented color epure of potential distribution and line of current density. Reinforced concrete construction current and current which flow into armature were determined by dint of integration of normal current density on surface where set the external potential and surface of armature. On the grounds of determine values of model current resistance of model depending on resistivity of concrete and ground were calculated.

This article presents promising and widely used in transport construction methods of earth bed reinforcement with the use of geotextile as a reinforcing and separating layer. It was suggested to lay down geotextile coverings manually in the zones of rail joints of an equalizing span of a continuous-flow track by 6-10 sleepers in each side of the joint, in all, 12-20 sleepers where high-speed and high-speed passenger traffic is expected. Basic technical requirements and restrictions on geometric dimensions for geotextile when reinforcing the main track bed are given. The technology of manual laying of reinforcing geotextiles when a small section of the railway track needs reinforcement during routine maintenance and repair of the railway track is given. The sequence of basic manual laying of geotextile coverings in the technological "windows" is described. Experimentally conducted work on the device coatings of geotextile manually in the areas of rail joints equalizing span of permanent way for 6 sleepers on each side of the junction in the railway sections of the Tashkent railway station (PCH-2). A design for reinforcement of the main ground in the areas of rail joints has been proposed. The basic requirements to quality control of construction works in structures with the use of a layer of geotextile materials are given.

The development of railway transport is currently impossible to imagine without the use of mathematical models and algorithms. Consider the increase in speeds, reduction of travel time, while minimizing costs, is possible only with the qualitative and full use of the mathematical apparatus. The use of information technologies makes it possible to take an effective decision in the development of a project for the reconstruction of a railway line. The current state of the theory of railway transport is characterized by the presence of a developed system of mathematical models and algorithms for analyzing various features of railways. This opens up possibilities for building an approach to the problems of searching and optimizing design solutions on a mathematical basis, with the reduction to a minimum of costly and time-consuming physical modeling procedures. One of the main tasks that are set for the railway transport in the near future is to increase the speed of trains on existing railway lines with the use of computer technology (computer-aided design). The article deals with the problems of technical reconstruction of the railway plan to increase the speed of train movement. The urgency of the use of computer mathematical methods for the development of an optimal plan for increasing the speed of trains. A pair of mutually dual problems of optimal reconstruction of railway curves to increase the speed of trains with minimal capital investment is considered. As methods for solving the problems posed, the following methods were proposed: the method of steepest descent, a modified method of dynamic programming (the Cattell method), the method of indefinite Lagrange multipliers. The expediency of using each method to solve the problem is indicated. The considered methods allow to implement a number of computer-aided design procedures for the reconstruction of the railway plan.

The models of complex organizational and technological parameters of operation of liner-straightening machines cyclic action on the example of the VPR-02 and VPRS-02 using a probabilistic assessment of the reliability of their work. For her study conducted two etapa checks: logical and mathematical. After sampling in accordance with GOST 8.207-76 inspect it belongs-rise normal distribution using Pearson's chi-squared test. Next calculated reliability and risk completion of the planned scope of work machine systems, complexes, components and individual machines in the planned period of time. The models are based on actual field tests of databases, technical and economic indicators of machines, components and systems in real operating conditions. This model optimizes track works with a given reliability at stave-builder, all kinds of repair and current maintenance of railway track. And also give the opportunity to the WHO-define more rational modes of operation of track machines for you, edits, tamping and straightening the railway line, thereby increasing pa O-workings of these machines. They enable organizations operating these machines more reasonably expect the required number of cars processes track works, their cost and labor. The proposed method models quantify the technical reliability of the liner-straightening machines; allow predicting the main complex organizational and technological performance of a particular machine at the design stage of technological processes track works. This method is versatile and can be used to evaluate the technical reliability of any machine systems, components and separate machines.

Increasing speeds on existing railway lines is one of the main challenges facing the Belarusian railway. Through the territory of the republic there are two transport corridors connecting Russia and Western Europe, as well as Ukraine and the Baltic countries. In all of the above countries, the increase in speed on the railways is very fast. Belarus can not stand aside. However, to increase the speed, it is not always enough initial information. To identify the necessary data, methods of decision theory are used. The integral probabilistic criterion method (CPI) allows one to substantiate the road parameters necessary for introducing high-speed traffic on existing lines. The proposed method of decision-making on the choice of technical parameters and equipment of the line, taking into account the uncertainty in the re-design for the high-speed movement of passenger trains. The initial data for determining the CPI is a risk matrix or a matrix of particular criteria. When using the risk matrix for each design decision option i, the dependences of the expectation of losses on the probability of realization of the design conditions p varying in the range from 0 to 1 are compiled. In the article on the proposed methodology, the reduced costs for the variants of design solutions are determined under all possible design conditions. Using these costs, a matrix of private criteria and a risk matrix are formed. A comparison was made of the design decision options for the integral probabilistic criterion, using which the recommendation of choosing the option is unambiguous and is accompanied by a quantitative assessment, which facilitates the task to the decision maker.

Shotcrete lining is one of the most common types of temporary supports in tunnel construction. The influence of shotcrete lining on design calculations of permanent lining is difficult, because there is no method of designing at the present time. This leads to increasing in consumption of materials and labour of construction. The information about the influence of the basic mechanical properties of soils, geometrical size of construction per value of temporary shotcrete lining factor was obtained during research. These data formed the basis for futher development method of designing.