The article presents the analysis results of influence of shape and dimensions of cross-section, laying depth of mine, cross-section shape and dimensions of underground mine on the daylight surface settlement of undermined territory depending on the different numerical values of the soil lateral pressure coefficient of the surrounding soil. The numerical solution was obtained in an elastic setting using the computer programs «FEA» and «Stability». In the calculations, the elastic modulus of the enclosing rocks is taken equal to the dimensionless constant E /γ H = 500 (where γ; H are the rocks volumetric weight and laying depth of mine), therefore, the numerical values of the vertical displacements gained as a result of the calculations are also dimensionless. This approach is convenient for both quantitative and qualitative analysis, because not only specific values of vertical displacements are considered, but also change patterns of their values depending on changes in the numerical values of the variables of the calculated parameters. Assuming that the displacements in the linear formulation of the problem are inversely proportional to the elastic modulus, their magnitudes can be determined for any other value of E . It was established the vertical displacements of earth’s surface points located above the mine, provided that the depth of its laying is more than 15.2 m and the dimensions of the cross section are greater than 4×4 m, significantly depend on the shape of the cross section and the lateral pressure coefficient of the surrounding rock. In addition, smaller vertical precipitation of the daylight surface corresponds to an underground mine having an exotic and «non-technological» cross section in the deltoid form. Therefore, the problem arises is to obtain such an optimal cross-sectional shape of the mine that would ensure the minimum precipitation of the earth's surface. The cross-sectional shape of the mine must be as “technological" as possible according to its advancement. The subject of further research is the solution of these problems.
The results of calculating the stability of a landslide-prone slope located on the river bank are presented. Additional stability studies were carried out due to the fact that, according to the results of slope calculations using various “compartments” methods, based on the construction of circular cylindrical sliding surfaces, the slope is in a stable state (tables are given containing the numerical values of the safety factors). However, in the spring-autumn period, local landslides occur on the slope. Therefore, new calculations of slope stability were carried out using a method based on the analysis of the stress state of the soil massif, which allows one to take into account the "weighing" effect of groundwater when it rises and the decrease in the strength properties of the constituent soils when they are soaked. This method is formalized in a computer program developed with the participation of one of the authors; the program has a certificate of state registration. Calculations have established that an increase in the level of groundwater to the maximum possible value reduces the values of the safety factors along the considered sliding lines by 5.9-21 %. It is shown that if the numerical values of the safety factors obtained by the methods of circular cylindrical sliding surfaces are reduced by 21 %, then some of their values will be very close to unity or even less, which resolves the above contradiction. When calculating the stability of landslide-prone soil masses, in which seasonal fluctuations of groundwater are possible, one should take into account the "weighing" effect of groundwater at the maximum level of their rise, a decrease in the physical and mechanical (strength) characteristics of soils due to their soaking and, preferably, the destabilizing effect of hydraulic heads.
The article describes a method of calculating the stability of fill slopes, including the construction of the most probable sliding surface and the determination of plastic deformations areas with elastic and elastoplastic (mixed task) distribution of stresses in the soil massif. The comparative stability calculations results of the "embankment - weak foundation" systems are presented, the data for which were taken from scientific articles published by other authors. According to these calculation results, the stress and displacement fields arising in the "embankment - weak base" system, the position and shape of the areas of plastic deformations constructed both on the basis of the Coulomb - Mohr strength condition and on the basis of solving a mixed problem of the theory of elasticity and the theory of plasticity of soils the article has comparison of numerical values of the stability coefficients and the safety coefficients of a weak. It is established that the replacement of the soil mass of the embankment with an equivalent load, as is often done in engineering calculations, significantly transforms the stress and displacement fields in the soil mass of the base, the position and shape of the areas of plastic deformation and, ultimately, entails obtaining unreliable results. The article shows the results of calculations performed using the FEA computer program developed by one of the authors and the Plaxis software package are in satisfactory agreement: the stress and displacement isofields practically coincide, plastic areas have similar dimensions, shape and position in the soil mass, which allows us to recommend the FEA computer program for practical use in calculating the stability of slopes and slopes, as well as the "embankment - weak foundation" system.
The article analyzes the experience of Russian cities that provide toll roads charging. Based on the analysis, rates for toll roads were proposed depending on the category of vehicles, corresponding to the volume and quality of services provided to the user of the toll road. Based on the data obtained and the methodology for calculating the rate for vehicles on toll roads, the calculation of the amount of savings received by users when driving a toll road, compared with an alternative free route, was made. The calculation included determining the cost of operating a vehicle when driving through a toll road facility by reducing the consumption of fuel and lubricants, tire wear, repair costs, and other items of operating costs. The advantage for users of toll roads was determined by saving time for delivery of goods and passengers, increasing comfort and traffic safety. Additional attraction of funds through placement of gas stations and advertising is considered. The payback period of the toll road has been determined. The conclusion is made about the need for further research on the problems of development of the network of toll roads.
At present, the age of most transport facilities in the Russian Federation estimated by many decades, and most require reconstruction or repair. Consequently, there is an urgent need for periodic surveys and monitoring of the condition of such facilities. The main goal of these measures is to maintain high rates of transport infrastructure efficiency, the achievement of which is impossible without examining, analyzing and evaluating parts of the structure in the aquatic environment, and, as a result, the occurrence and development of various defects and damage. The most important conditions for ensuring uninterrupted and safe traffic on the bridges of vehicles and pedestrians are the regulatory bearing capacity of the structure and cleaning of the roadway and sidewalks. Then compliance with traffic safety requirements on decks and observing the characteristics and maintaining the function of the bridge for the period of ice drift and flooding. Timely execution of works for the care, maintenance, and repair of bridge elements. Technically stable structures and their reliability can be ensured by observing all the parameters of the structure of the road category and the requirements of regulatory documents. The paper presents the materials of the inspection of the bridge after repair — defect classification by groups and hazard classes — the results of determining the carrying capacity of the survey materials given.
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