Introduction. Construction of engineering structures is impossible without building and road machines. The large volume of financing is allocated for such machines’ purchase. The main ways of reducing costs of the equipment consist in more rational operation of the equipment and also in decrease of equipment’s cost by constructive changes. The paper demonstrates the new design of the single-bucket hydraulic excavator with smaller cost.

Materials and methods. The main ways of cost reduction for construction machines are more rational operation and depreciation of a design with the required characteristics’ maintaining. The paper describes constructive changes of the working equipment of the single-bucket hydraulic excavator, which allow decreasing the production costs.

Results. The authors describe the new bucket design of the single-bucket hydraulic excavator. Moreover, the authors carry out the analysis of the existing buckets’ design. The paper also illustrates the functioning on bucket forces while digging process. The authors describe the solutions of the problem for productivity increase of the single-bucket in hydraulic excavators. In addition, the authors make the scheme of the bucket loading while digging process. Such scheme helps to reduce resistance forces of digging.

Discussion and conclusions. As a result, the paper presents the design of the working equipment of the hydraulic excavator’s single-bucket, which allows reducing resistance forces of digging. Such results would help to establish buckets of bigger capacity and would lead to the productivity increase.

Introduction. In order to save resources, in many countries of the world the raw materials’ re-use method is used. Machines such as recyclers are used to recycle asphalt concrete. The durability of the road surface depends on the quality of asphalt concrete mix. The process of mechanical mixing plays a very important role in the substance homogeneity obtained during the mixture production. Therefore, it is necessary to study the basic mechanism and method of mixing.

Materials and methods. The authors used the basic laws of hydrodynamics and solved the equations of the similarity theory.

Results. As a result, the authors considered the power by the mixer and the power that was necessary to obtain the desired quality of the mixture. The paper described the required number of revolutions of the stirrer for the preparation of suspensions and emulsions, taking into account the energy efficiency of the mixing process.

Introduction. Rotary cultivators are necessary for circular soil cutting while forming the underlayment and slopes of highways. Therefore, the objective of the research is a theoretical substantiation of constructive and sensitive parameters for the rotary ripper. The researchers usually use synthesis method to evaluate theoretical evaluation of the energy consumption on the development of soil. The researchers also carry out an indicative calculation of basic design parameters and power drive of rotary ripper.

Materials and methods. The author developed a methodology for calculating the indicative rotor power. Moreover, the author detected changes of the effective frontal sections of the working body in the process of the rotor circulation by means of the length measuring of a frontal section.

Results. As a result, the author defined rational working parameters of circular cutting ground and calculated the angular velocity of the active working body. Moreover, the author also identified the required average torque and approximate rotor power.

Discussion and conclusions. A simple and intuitive method based on accepted formulas of strength of materials, theoretical mechanics and other sciences is required for practical calculations of the working vehicles’ bodies. The author finds out that on the basis of the synthesis method the assessing energy expenditure on the development of soil may be defined, the analysis of the interaction with soil working bodies can be made.

Introduction. City passenger transport plays an important role in life of the population of the city and in ensuring the efficient, uninterrupted operation of the entire urban system as a whole. However, currently in the field of urban passenger transport in many cities of Russia a number of significant problems have accumulated. In particular, these are problems of the development of the urban route network, the performance indicators of which determine the level of quality of transport services for the population and the economic effect of the operation of urban passenger transport. In this connection, the study of the prospects for the development of methods for optimizing the urban route network becomes relevant.

Materials and methods. The article presents a chronological analysis of methods for optimizing route networks of urban passenger transport. It reflects the specifics of their use, shows the advantages and disadvantages. The authors also reflect the trends in the development of modern methods of optimization of route networks of urban passenger transport. The existing numerous methods for optimizing urban route networks could be divided into two types: heuristic, which have become classical today, and qualitatively new ones – metaheuristic, allowing managing tasks that contain nonlinear functions in the process of optimizing urban route networks. As modern science, software and computing facilities in the studied area have been developing very fast, metaheuristic methods are becoming a promising direction.

Results. It had been revealed that over time, methods for optimizing the route networks of urban passenger transport had been improved and made it possible to take into account the opposing interests of the participants in the passenger transportation process in the city, as well as to set a large set of initial parameters and constraints for a mathematical model for optimizing the urban route network. The authors revealed the main features of the optimization of the route networks of urban passenger transport in the conditions of the modern development of science and software and computing facilities in the studied area. To date, there were no exact optimization methods for optimizing urban route networks. The task of optimizing the route network appeared to be combinatorial.

Discussion and conclusions. The research is useful not only for the further development of science in the area under study, but also for the practical implementation of the process of optimizing the route networks of urban passenger transport.

Introduction. The actual problem in Russia is the accident rate at pedestrian crossings. The authors conduct the research about the lighting conditions on unregulated pedestrian crossings to improve safety and to identify compliance with current regulations. Moreover, International and Russian researchers point out a large role in ensuring visibility of pedestrians. Increasing of the roadway lightness improves the visibility of pedestrians at night, especially at pedestrian crossings. In addition, world practice shows that after improving the road lighting the number of accidents with pedestrians decreases.

Materials and methods. The authors selected unregulated pedestrian crossings, which were the sources of accidents in dark period. The light level was measured using a Victor 1010A light meter. The authors carried out the dimensions at night in clear weather without precipitation, when artificial lighting was turned on.

Results. The research revealed that the lighting at pedestrian crossings and especially at the crossings’ approaches did not correspond to standard values even with the artificial lighting. Therefore, the lighting on approaches was important for early pedestrians’ detection by drivers.

Discussion and conclusions. As a result, the authors present the recommendations for the insufficient visibility’s elimination at the pedestrian crossings. The authors also justify the need to control the lighting level at all unregulated pedestrian crossings and approaches to them.

Introduction. The authors propose to use a rational distribution of buses, taking into account their passenger capacity and the hours of the day, in order to optimize the operation of the rolling stock (RS) on the route. The usage of RS low-capacity on routes with significant passenger traffic increases the RS need, the load on the transport network and emissions of harmful substances into the atmosphere. Operation of high-capacity buses on routes with low power passenger traffic leads to the large intervals of movement and to the increase of waiting time for passengers. The authors highlight that on the number and type of buses’ determining it is necessary to take into account the city specifics (on the example of Volgograd), such as the presence of only two main streets with three lanes in each direction, adjacent roads through which the routes pass, one lane direction.

The length of the city along the Volga river in total is about 90 km, due to the peculiarities of the road network (RN) of the city, any irrational use of the RS leads to a significant load on the road network, and, as a result, to the congestion on the roads. Nowadays the PS is not operated effectively.

On most routes of the city the capacity of RS does not correspond to passenger traffic on the route. Possible way to optimize the use of RS is taking into account the daily load on the road network.

Materials and methods. The authors studied the technology of the movement organization of the rolling stock on the № 59 route. In order to optimize the transportation process, the authors used the method of determining the buses’ number by hour of the day on the base of the graph-analytical method. Buses of different capacity were used on this route.

Results. The resulting distribution of buses made it possible to combine the interests of carriers and passengers, to increase the efficiency of rolling stock and to reduce the load on the road network.

Discussion and conclusions. As a result, the authors present the measures for improving the efficiency of the rolling stock. These measures are the main for improving transport services for population.

Introduction. At present, stands with running drums are widely used for various types of tests. Power stands play a special role. Such stands take the mechanical power from the driving wheels of the car. This simulates the process of movement of the vehicle under operating conditions. Such equipment has various designs, principles of operation and performance. It is also used in tests that are different by purpose, development stages and types: research, control, certification, etc. Therefore, it is necessary in order to determine the traction-speed, fuel-efficient and environmental performance characteristics.

Materials and methods. The paper provides the overview of the power stands with running drums, which are widespread on the domestic market. The authors carried out the analysis of the main structural solutions: schemes of force transfer between the wheel and the drum; types of loading devices; transmission layout schemes and features of the control and measuring complex. The authors also considered corresponding advantages and disadvantages, recommended spheres of application, demonstrated parameters and characteristics of the units’ workflow, presented components and equipment.

Discussion and conclusions. The authors critically evaluate existing models of stands with running drums. Such information is useful for choosing serial models of stands and for developing technical tasks for designing or upgrading the equipment.

Introduction. One of the most important indicators determining the public transport service quality is the capacity utilization factor of transport fleet. This parameter directly effects on the economic efficiency of the transport organization. For the carrier it is desirable from an economic point of view that the value of the capacity utilization factor takes on the greatest value. Passengers, on the contrary, prefer to transfer without overfull capacity of transport vehicles. Moreover, this factor is used in determining travel fares, analyzing the executed movement regarding the availability of reserves in carrying capacity and planning transportation process. The paper discusses the method of marginal value calculation of the transport fleet’s capacity utilization factor of urban public transport based on ensuring standard vehicle's cabin filling limits.

Materials and methods. The authors solved the task of determining the filling marginal value for transport fleet while working on regular urban routes by analyzing the dependence of the capacity utilization factor on the passenger traffic parameters, the average operating time of the transport fleet on the route and the speed fluctuation during public transport operation. The authors also proposed the indicator of the transportation speed fluctuation during the operation of urban public transport.

Results. The authors found out that the capacity utilization factor of transport fleet substantially depended on the passenger traffic parameters, on the average operating time of the transport fleet and on the speed fluctuation during public transport operation.

Discussion and conclusion. The obtained dependences allow us calculating the marginal values of capacity utilization factor with taking into account the parameters of the planned transport process. The standard capacity utilization factor varies within considerable limits from 0.2 to 0.4, depending on the operating conditions.

Introduction. The paper deals with the results of the reliability of urban public passenger transport routes. One of the main objectives is to consider the indicators for assessing the reliability of the urban passenger transport system, which have not yet been used in Russian practice. The peculiarity of these indicators is that the initial information can be obtained on the basis of modern bus equipment (GLONASS/GPS). The possibility of using these indicators, as well as the development of scales of reliability levels at the moment is an important scientific problem.

Materials and methods. The authors proposed modern indicators for assessing the reliability of urban passenger transport routes, such as the time index and the associated buffer time indicator. The authors used the methods of mathematical statistics to process the data on the duration of bus traffic.

Results. The authors obtained the reliability characteristics of urban passenger routes. Moreover, the paper presented the comparison of the reliability values on the example of Irkutsk and Angarsk.

Discussion and conclusions. The authors reveal the range of values of the time and buffer indices based on the data of route networks of two different cities. Therefore, the authors offer the estimation scale of the reliability levels on routes.

Introduction. The paper is devoted to the problem of organized children transfers by road transport (buses) in intercity connection. Nowadays, according to the legislation of the Russian Federation, children are on the way during the organized transfer no more than 4 hours. Meanwhile, the process of the children transfer is considered without taking into account age groups and this process is regulated by rest time of drivers. The objective of the paper is the actualization of the organized children transportation by buses in intercity connection and of the organization method taking into account age features.

Materials and methods. The authors used the method of statistical and systematic analysis, the method of expert estimates, technical expertise, the theory of the passenger transport by road transport and also other techniques and methods of scientific research.

Results. As a result, the authors suggested taking into account the regularities of distance and time of the transfer by the age of children and in adjusting of driving conditions and rest time of drivers and also in organization of tourist routes.

Discussion and conclusions. The authors recommend to use the results of the research for children and youth tourism organization and for the organized carriage of children groups by road transport (buses) in intercity transfers.

Introduction. The manuscript is devoted to the actual problem of thermal insulation of buildings and structures. The paper presents a developed low-density insulation solution with improved heatengineering characteristics. The aim of the work is to increase the efficiency of the heat-shielding system using a low-density heat-insulating solution.

Methods and materials. The authors carried out tests at the site of heat engineering control of LLC «Intellect-service-ZBK-1» to determine the resistance to heat transfer of the enclosing structure.

Results. The construction of the wall system consisting of the «Aerobel» D500 gas-silicate block (625×200×250 mm) and made on a low-density heat-insulating masonry mortar, as well as with the use of a heat-insulating mortar and a universal «Moutrical» energy-efficient coating allowed increasing actual reduced heat transfer resistance from 0.9 to 1.4 (m2 ·K) / W (by 36%).

Discussion and conclusions. Laboratory research and field tests that meet the requirements of state standards and that develop low-density heat-insulating plaster demonstrate the low-density heatinsulating solution, which indicates the feasibility in thermal insulation of buildings and structures. The authors achieve special economic and ecological effect in connection with the use of local raw materials and waste production of expanded perlite sand.

Introduction. The objective of the research is to study the effect of the complex activation of the alumina raw material on the rheological properties of the ceramic mass. In addition, the authors investigate solutions for the application of optimal coagulation structures based on loams and ash together with plastic certificates.

Materials and methods. The authors used the local forest like reserves of clay loams at the BashKarasu, ash fields of the Bishkek Central Heating Centre (BTEC) and plasticizer (sodium naphthenate obtained from alkaline chemical production wastes) as fibrous materials. Moreover, the authors defined technological properties of raw materials within standard laboratory methodology in accordance with current GOSTs.

Results. The researchers tested plastic durability on variously prepared masses for the choice of optimal structures. The paper demonstrated the plastic durability of complexly activated compounds comparing with non-activated and mechanically activated compounds. The sensitivity coefficient increased the amount of clay loams by mechanically and complexly activated, which predetermined the possibility of intensifying the process of drying samples based on complexly activated masses.

Discussion and conclusions. However, mechanical activation of clay material reduces the period of relaxation and increases the elasticity coefficient of ceramic masses by 1.8–3.4 times, meanwhile decreases elasticity, viscosity and the conventional power during molding, which generally worsens the molding properties of the masses. Сomplex activation of ash-clay material decreases the period of relaxation and provides an increase in elasticity, plasticity of ceramic masses by 46–47%, reduction in viscosity by 1.5–2 times, conventional power on molding by 37–122% in comparison with MA clay loams. Ceramic masses based on spacecraft alumina raw materials belong to the SMT with improved rheological properties; products based on them pass through the mouthpiece for 5–7 seconds.

Introduction. The creation of energy-saving materials involves the use of local raw materials for products with improved physic-mechanical properties. The author carries optimization of the rational composition and properties of modified arbolite from plant-gypsum composition (PGC). In addition, the author uses modifiers on new ways of preparing the aggregate according to the method of experimental and statistical modeling.

Materials and methods. The author used the cereal straw grown in the Kyrgyz Republic (CS), G-5 and G-7 construction gypsum based on local raw materials, ash from the Bishkek Heat and Power Plant (BHPP), portland cement clinker PCC, natural clay (ganch). Moreover, the clay component of the Toloykonsky deposit was used as the clay component. The author also added the liquid glass, latex SCS, the low-concentration resin LCR-3066 + catalyst of ionic type (CIT) as modifiers for the formation of the porous polymer-silicate systems. The paper marked the plasticizing additives in the manufacture of arbolite as SCS, LCR and CIT components. As a retarder the setting of gypsum was added a partial salt 1-hydroxyethylidene-1, 1-diphosphonic acid with triethanolamine and flame retardants. The tests were carried out according to standard methods. To optimize the composition and properties of the polymersilicate-gypsum composition (PSGC), the author carried out a three-factor experiment according to the B3 plan, where three prescription factors varied: X1 – straw content,%; X2 – content of polymer silicate additives (PSA) + plasticizer,%; X3 – gypsum content + portland cement clinker as a nitroperimethyl phosphoric acid (NPA) and flame gypsum retarder.

Results. The research showed that at 28 days of age for cement-free gypsum compositions as the content of straw increased, the strength was almost unchanged. When comparing the strength of the same samples of 2 and 28 days strength with the maximum filling of gypsum, the author defined that the PSA content should not exceed 12% when the straw additive was 26% and further PSA increasing did not increase the strength.

Discussion and conclusions. As a result, the author achieves maximum strength of the arbolit, when the content of G-7 gypsum is 28-32%, ash is 18-22% and PSC is 8-10%. The maximum value of strength and water resistance of the material is achieved with a rational ratio of components: straw – 24–28%, G-7 gypsum – 30–32% + NSPL – 0,05%; ash – 18–22%; resin – 3066-8-12% + catalyst – 0,3% (87% sulfuric acid, 13% phosphoric acid); PCC – 3–5%; clay-gypsum (ganch) – 2%; liquid sodium glass – 12%; plasticizers CIT – 0,15%, SCS – 0,2%, LCR – 0,15%; modified hardener – 0,5% and water.

Introduction. The paper presents the results of research that allow assessing the degree of influence of pre-organized cracks on the character crack formation and on the process of the hollow-core slabs’ deformation under short-term load action.

Materials and methods. The hollow-core slabs are made without prestressing – one by traditional technology, the second with pre-organized cracks in the manufacturing process. Physical experiment performed on fall-scale structure of hollow-core slabs of П66.10-81500СП. The authors conducted the tests to the calculated breaking load. Moreover, the authors presented the contrastive analysis of character crack formation and of the hollow-core slabs’ deformation of П66.10-8А500СП traditional manufacturing and with pre-organized cracks.

Results. As a result, the authors confirmed the earlier hypotheses about the greater rigidity of plates with pre-organized cracks in comparison with the plates where the cracks arose stochastically and under operational load. The installation of organized cracks did not reduce the bearing capacity, thus, reduced the deformability. Therefore, the width of the crack became smaller and the deflections became less.

Discussion and conclusions. In the structures of long length, which are rejected by the second limit group, the organization of cracks at the manufacturing stage allows not putting additional reinforcement to reduce the width and deflection of the crack.

Introducton. The paper demonstrates the results of experimental research of the reinforced concrete shell-slab under the action of vertical uniformly distributed load. The authors also present the comparison of such research results with the results of stress-strain state evaluation performed in the “Lira” software package.

Materials and methods. The authors tested the reinforced concrete model representing physically similar copy with the 1:5 scale coefficients by general size, and by separate details. The load was applied in 10–15% doze of the theoretical bearing capacity of the plate.

Results. The authors calculated the experimental transverse stress σ_х,3,exp, which was in full-scale construction and in the 3 central sphere. The authors also made the comparison of such transverse stress with theoretical transverse stresses σ_х,3,teor and the comparison was performed in the “Lira” program complex. The diagrams of the above stresses were well matched by outlines and values.

Discussion and conclusions. As a result, the experimental (σ_{x, 3,exp}.) and theoretical (σ_x,3,theor.) stresses are compressive near the shell-slab center. Its maximum stress values (σ_{x, 3, exp}) reach x/b=0,5 at a point with a relative coordinate, and the stress (σ_x,3,theor.) – x/b ≈ 0,45.

The zero voltage values σ_x,3,exp. reach a quarter of the shelf width, theoretical stress –with x/b ≈ 0,3 mm ratio.

Maximum values of experimental and theoretical tensile stresses σ_{x, 3} reach x/b ≈ 0,15 ratio. Therefore, the values are close to each other, and do not exceed the standard concrete tensile resistance R_{bt, ser}.

The practical significance of the study is to obtain experimental evidence of the abandoning possibility of the horizontal transverse reinforcement of the shelf, which would reduce the complexity and cost of the investigated structures production.

The prospects conclude in:

research of the shell-slab operation at the stage of ultimate equilibrium;

research of the shell-slab crack resistance and stiffness at all stages of its operation;

research of the shell-slab operation taking into account the fixation in the transverse direction of its longitudinal contour edges along entire length.