The presence of analytical dependencies describing the process of static soil puncture by a working body with a conical asymmetric tip is necessary to create installations with the ability to control the trajectory of the soil puncture.
The paper considers the features of the process of interaction of an asymmetric conical tip with the ground. Analytical relationships were obtained to determine its reactions during a static puncture, the deviation of the head trajectory from a straight line, to determine the size of the soil compaction zone and the magnitude of the destructive force that acts on adjacent communications and other underground objects. It was found that with an increase in the value of the displacement of the top of the cone, for example, from its axis from 0.02 m to 0.08 m with a borehole diameter of 0.2 m, the value of soil resistance increases almost four times. The greatest resistance is achieved when piercing a hard sandy sand.
It was found that with an increase in the displacement of the tip of the tip cone, the deviation of the trajectory increases. The piercing head achieves the greatest deviation from the straight trajectory of movement with a sharper cone and a greater asymmetric deviation of its top, and, for example, in hard sandy loam can be up to 0.17 m with a span of 10 m.
It was found that the size of the soil destruction zone will be almost 1.8 times larger than the tip in the form of a symmetrical cone and reaches from 8 to 12 borehole diameters, depending on the type of soil. The maximum pressure on adjacent objects can reach from 0.06 MPa in hard-plastic clay to 0.09 MPa in hard sandy loam.
The calculated dependences obtained for determining the power and technological parameters depending on the geometric dimensions of the asymmetric tip of the working body can be used to create installations with a controlled static puncture for use in the most common soil conditions.

/pdf/determination-of-the-regularities-of-the-soil-punching-4jf7wke9dt.pdf

Determination of the regularities of the soil punching process by the working body with the asymetric tip

S. Raksha: ORCID 0000-0002-4118-1341; O. Kuropiatnyk: ORCID 0000-0001-5581-3883; O. Krasnoshchok: ORCID 0000-0002-0140-5179

/pdf/justification-of-criteria-for-ropeways-energy-efficiency-45muv7dgsg.pdf

Justification of Criteria for Ropeways Energy Efficiency

O. Kuropiatnyk: ORCID 0000-0001-5581-3883, S. Raksha: ORCID 0000-0002-4118-1341, .P. Anofriev: ORCID 0000-0001-7997-3523

/pdf/justification-of-parameters-of-wheelset-axle-fatigue-5bcint20s1.pdf

Justification of Parameters of Wheelset Axle Fatigue Strength Test-Bench for Railway Rolling Stock

One of the tasks that need to be solved in order to predict the life of wheelsets is to assess the contact strength and wear of their parts. Thus, the purpose of this work is to develop a scheme and justification of the parameters of the life-test bench for railway wheelsets in conditions close to real operating ones. This bench simulates a contact of “wheel-rail” pair as a contact of “wheel-roller” pair. To ensure compliance of the bench tests conditions with the real wheelsets operation conditions we took that the maximum contact pressure in the “wheel-roller” pair is equal to the maximum contact pressure in the “wheel-rail” pair. As results of this study we obtained the dependences of the values of the roller diameter and the working force of the bench on the characteristics of the tested wheelset and proved the mutual influence of these quantities. For railway wheelsets with an axle load of 230.5 kN and wheels with a tread diameter of 957 mm, we obtained the following values of the bench parameters: roller diameter is 75 mm; working force of the bench is 8,375 kN; wheel speed is 500 rpm; number of rollers is 8; test duration is about 220 h.

Justification of the parameters of the life-test bench for railway wheelsets

Purpose. The purpose of the work is to determine and analyze the technical parameters of the bench for railway wheels complex tests, providing for the combination of fatigue and contact strength tests, their simultaneous performing on same test-bench. Methodology. Determination of the technical parameters of the test-bench was carried out based on comparing the characteristics of fatigue and contact strength tests of railway wheels. Requirements for fatigue tests and related equipment are determined based on an analysis of the current regulations and patent review. A model of the contact strength test-bench with the introduction of necessary changes in terms of ensuring the cyclicity of the working effort application was adopted as the basic model for the development of a complex test-bench. The criterion for the possibility of complex tests, involving the simultaneous testing of railway wheels for fatigue and contact strength, was the dependence of the test-bench roller diameter on the parameters of the tested wheel, the wheelset axle load, which includes the tested wheel and the wheel material endurance limit. Findings. The analysis of the obtained dependence showed that the roller diameter as a function of the load in the contact zone of the “wheel – roller” pair has second order discontinuity in the section where this load changes from the minimum to the maximum value. Analytical dependence is also presented and analyzed in graphical form. The generalization of the results obtained made it possible to conclude that it is impossible to carry out complex tests of railway wheels, which provide for the combination of fatigue strength tests with contact strength tests, subject to their simultaneous holding at the same test-bench. Originality. For the proposed scheme of the bench for complex tests of railway wheels, for the first time, we obtained the dependence linking the parameters of the test wheel, the parameters of the bench, the wheel pair axle load and the wheel material endurance limit. Practical value. The results obtained can be used as a basis for the development of new test-benches for railway wheels.

/pdf/determination-and-analysis-of-technical-parameters-of-the-k1gsvgyt4j.pdf

Determination and analysis of technical parameters of the bench for railway wheels complex tests

Wheelset axles are essential parts of railway and mine site rolling stock. For fatigue testing of axles, various test-benches are designed to implement the cyclic loads. The effectiveness of test-bench vibration analysis grows with the use of numerical approach and simulation models created with the aid of visual programming tools. The purpose of the work is to develop and assess the proposed simulation models of test-bench dynamics created with the aid of visual programming tools. Based on mathematical models, the test-bench simulation models of the lever system vibration have been developed. Simulation models are created with the aid of Simulink visual programming tools running under Matlab system. For modelling the components of Simulink, the SimMechanics and DSP System Toolbox Libraries are used. The comparative analysis of proposed models has been made. For the first time, with the aid of Simulink visual programming tools, the set of test-bench vibration simulation models has been obtained in steady-state and transient motion modes for linear task formulation. The proposed S-models allow automation and visualization of the motion dynamics study for test-bench components in order to determine their rational elastic-weight, kinematic and dynamic behavior. Simulation of vibrations was carried out using design parameters of the test-bench metal framework.

/pdf/simulation-modelling-of-the-rolling-stock-axle-test-bench-5589ilib5c.pdf

Simulation modelling of the rolling stock axle test-bench

S. Raksha: ORCID 0000-0002-4118-1341, O. Kuropiatnyk: ORCID 0000-0001-5581-3883, P. Anofriiev: ORCID 0000-0001-7997-3523

/pdf/frequency-analysis-of-vehicle-drive-with-cable-traction-2sxv0z15qb.pdf

Oleksii S. Kuropiatnyk

Papers

Simulation modelling of the rolling stock axle test-bench

Frequency Analysis of Vehicle Drive with Cable Traction

Justification of Parameters of Wheelset Axle Fatigue Strength Test-Bench for Railway Rolling Stock