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The results of field researches of the oscillatory process subgrade erected with sand dunes. The analysis of the oscillations records of particle of sand dunes at the main field, in the frame and be-hind of the subgrade. Given findings change of the value of oscillation amplitudes of dunes sand depending on the speed of trains. Analytical dependence of definition of attenuation of fluctuations in a body of subgrade from sand dunes and behind its limits is revealed.

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 technique and algorithm of definition of consumption rates of materials on the current maintenance of a way depending on freight density, the passed tonnage, the plan and a profile of sites of a way, axial loadings of a rolling stock is given. Standards are developed on the basis of the analysis of the existing normative documents, statistical data from forms of primary accounting of PU-74 of the consumption of materials, annual reports of linear sites and other sources. Depending on service conditions standards are determined by analytical dependences and the correcting coefficients.

Example of the methods to evaluate conditions and reserve of transverse stability in CWR curves under abnormal track maintenance is discussed in the article. The author presents the results of the research of this method and also its positive effect is described.

The algorithms and modeling program allowing estimating indicators of financial technological risk, based on a random process of dynamic risk.

Evaluation of fatigue life is based on the use of basic fatigue curves. However, due to large va-riety of possible design solutions basic fatigue curves cannot be calculated for all cases. In addi-tion, the production practice has a significant influence on the durability of structural elements. To predict the fatigue durability using the traditional method we need to consider the influence of structural and technological factors by introducing the correction coefficients established on the basis of the experience and accumulated experimental data. The correction coefficients are widely used in calculating the resource elements by domestic and foreign construction firms. Using the traditional method the match of the projected longevity and durability resulted in a bench test struc-tures are not always satisfactory. Often by conducting rapid analysis the sufficient fatigue curves absent, the closest in characteristics among the available are selected. The article presents the im-proved technique of numerical fatigue life prediction of structural elements by using the modified fatigue curves, considering the impact of structural and technological features of the products of the actual design. The results of calculated estimate of the resistance of fatigue thin-walled struc-tures and their comparison with experimental data are presented. On the basis of the work carried out was drawn the conclusion that by using the method of calculation of fatigue longevity using modified fatigue curves , considering the structural features fragments of products, the convergence of the results of predicting fatigue life and test bench results obtained higher than by using tradi-tional techniques.

Some aspects of soil testing are discussed this article to determine the stamp bearing capacity of piles. The techniques of plating tests has been proposed with anchoring of the shell or casing piles future. This method allows you to evaluate the resistance of piles on its end and side surfaces.

The possibility of fatigue crack propagation in the region of compression stresses is considered. After each semi-cycle of cyclic loading the stress-strain distribution near the tip of the crack is determined by the finite element method. It is shown that maximum of the tension stresses increases in the region of compression. The obtained results allow to present the possible ways of the above-mentioned fatigue crack propagation.

The results of the study the strength characteristics of loess loam under triaxial when exposed vibrodynamic load of high-speed trains. Research carried out on triaxial vibration, based on the principle of operation of the plant simulation vibrodynamic exposure to periodic changes in hydrostatic pressure in the working chamber triaxial. The experimental values of specific cohesion and angle of internal friction, and the values of their relative decline under the influence of vibrodynamic load.

The paper proposes a method of measuring the transverse displacements of the rails. Made a priori error estimate. A version of the sensor and the concept of construction equipment.

Vibration levels in the subgrade for the movement of trains are investigated. analysis of the recorded accelerograms is made, acceleration fluctuations on the cross section of the embankment are installed. Calculations of the stability of embankments with the effects by the train load are produced.

It is considered how reliability of the grinding technology influences on the quality parameters of the treated surface. The results of analysis of relationship between quality of the rails grinding and conditions of its treatment are represented. Factors affecting on reliability of the technology are reviewed also. The model determining the reliability of the rails grinding technology in the railway is represented. Also the algorithm of calculation of the grinding technology reliability is represented. It’s reviewed how the quality parameters are formed during the rails grinding.

Research the fatigue crack initiation and the fatigue crack growth in rail with thermomechanical damage. On basis of cyclic test and numerical simulation of rail deflected mode was determine a fatigue failure characteristics and fatigue crack growth characteristic in rail steel.

Data on corrosion fatigue damages of a sole of rails (defect 69) on the railroads of Russia are submitted. It is established that 69 the corrosion fatigue resulting from moistening of a sole in a zone of contact with subrail laying in combination with the high level of the stretching tension in a rail sole is the reason of breaks of rails on defect. The analysis of statistical data on refusals of rails on defect 69 in the West Siberian management of infrastructure showed that failure rate grows to an operating time of the tonnage of 800 million t gross and has fatigue character. On sites of a way with a complicated plan and a profile failure rate is 3 - 4 times higher, than on quiet Trans-Siberian to the course. Results of the analysis of data are shown and measures for increase of reliability of the rail lashes having tendency to formation of defects on a code 69 are offered.

The increased influenceof cable-stayed - suspension bridges for crossing of sea passages is shown. The retrospective show of their development is given. The prospect of the big beam - combined bridges is resulted. Various schemes of vantovo-suspension bridges with rectilinear cables are considered. Two new schemes of cable-stayed suspension bridges with curvilinear cables are offered.

In research consider a methodology the remaining life assessment of rail with fatigue crack in lower flange. Obtain the stress intensity factor equations for crack size and kind of stress: bending stress, thermal and residual stress. Make up an fatigue strength analysis of rail P65 and under different conditions of loading and remaining life calculation of damaged rail when given conditions of loading. Submit a assessment evaluation rail reinforcement in cyclic crack growth rate.

This article contains information on the main pollutants and weeds on the railway. In the article the questions of the intensity of the contamination of the broken stone ballast. Specified criterion for assigning secondary and preventative maintenance of way in accordance with the technical specifications. Given reasons for the increased intensity of the contamination of the ballast in the first year of life. The analysis contamination of the broken stone layer in areas the Trans-Siberian Railway and the Medium-Siberian Magistral. The Trans-Siberian railway is considered towards Chelyabinsk - Karbysheva - Novosibirsk, the Medium-Siberian Magistral in the direction of the Input - Irtysh - Medium-Siberian. The analysis was conducted based on the data of geological investigations design and survey institutions and to schedules of repairs for the West Siberian infrastructure Directorate. For ease of estimation of the parameters of weeds the resulting material was consolidated into a single table. Based on the table were revealed of the according contamination of crushed stone ballast thickness, ballast layer, from the conceded tonnage and length of operation in years. The article describes the structure of the pollutants by particle size, in terms of pass excess tonnage. Indicated levels of contamination of crushed stone ballast at different values of the missed tonnage (700 million tons 1200 million tons and 1400 million tons). Additionally, this work was determined the average level of contamination of the ballast particles less than 25 mm, 5 mm and 0,1 mm) and obtained a limit value of the allowable clogging the broken stone ballast more than 30 percent. The result revealed the need for reducing the contamination of the broken stone ballast by conducting a deep cleaning.

The work is devoted to experimental study of the roadbed, filled from loess-like sandy, namely, characteristics dynamic vibration impacts arising from the passage of rolling stock, to establish the nature of the damped oscillation, the analytical expressions that can be used to estimate the bearing capacity of the subgrade to the dynamic vibration load.

In the article the issues on creation of branch of track width when changing it in the curved track with radius less than 350 m. Presented the existing methods of widening or narrowing the width of the track in the curves section of track. We propose a method of change of gauge in curved track is from 1520 to 1530 or 1535 mm. to the Proposed method of drainage of the track width is carried out by the existing structures of the elements of the superstructure. The proposed method of drainage of the track width gives a smooth fit of the rolling stock in curve track section and provides the requirements of the applicable standards.

The reinforcement of a soil subgrade by solidifying grouts injection, outside the limiting dimensions of train movement, can significantly increase the cost efficiency and manufacturability of strengthening. The paper suggests the most appropriate methods to strengthen the subgrade depending on the stage of defects and deformations development.

Method of calculation of reliability of rails are presented in article. Research of refusals and durability of rails on two directions of the West Siberian management of infrastructure for sites of a way with different operational characteristics is conducted. Dependence of a gamma percent resource of rails on axial loading of cars and the plan of a way is received. Conclusions about a possibility of reaching of the passed tonnage of rails in 1500 million tons gross are given.

The method and research results of information obtained by track management cars about the track state for planning track repair work to eliminate track defects have been shown. The defect types and their degrees measured by the relevant assessment method as well as the lengths of deviation from the rules of track maintenance have been analyzed. This was possible due to the latest versions of the software installed into track management cars of the КВЛ-П system. The scope and sequence of repair track work depending on their urgency, top-priority and schedule under structural and seasonal conditions has been determined. The conclusion concerning the efficiency of the presented method has been made.

The use of three-dimensional reinforcing structures is an effective method strengthen the slopes and the primary site of subgrade, it is confirmed by a complex of experimental studies. The numerical and natural modeling processes associated with the strengthening of subgrade geokompozitn structure. Natural modeling performed by the embankment of equivalent materials using real ground conditions and loadings identical in size natural. A comparison of simulation results showed high convergence, which allows use it’s in the preparation of design techniques.

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.