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String Transport Systems: aspects of mechanics at high-speed transport

We offer to your attention the next film in the series "String Transport Systems: on Earth and in Space", in which we talk about the scientific monograph of the scientist and inventor Anatoly Yunitskiy.

The third release reads about the complex of theoretical and applied problems, the successful solving of which allows the rolling stock in string transport systems to develop high speeds of movement.

Translation of the video:

In previous videos on Chapters 1 and 2 of Anatoly Yunitskiy's monograph "String Transport Systems: on Earth and in Space", we have already discussed with you SkyWay track structure and rolling stock, and today we'll talk about the 3^rd Chapter entitled "Aspects of mechanics at high-speed transport".

Its beginning describes the dynamics of transport modules movement along the guide string-rail, and because of very high requirements to strength parameters of high-speed transport of SkyWay type, it deals with the solution to a complex of theoretical and applied problems.

In a high-speed transport system, the dynamic stiffness is more important than the static one. There have already been researched and determined the design features of the track structure and the motion duties for unibuses, at which there are no resonance phenomena in the string-rail at speeds up to 500 km/h. Moreover, vibrations of the track will occur and remain behind a moving transport module, they will fade away within 0.1-0.5 seconds, and the next rolling stock will run on an undisturbed, perfectly smooth track.

Based on the existing calculation methods, the author describes the specifics of strength assessment of rolling stock and string guide rail determining the safety of SkyWay operation. Here he has applied the same principles that were used when designing a suspension bridge: one or the other element has to damp vibrations of the structure in its frequency range.

Thus, elements with different functional properties (high-strength strings, damping fillers, thin-walled protective casing, if necessary, a special head with high contact stiffness and anti-friction coating) provide the required features of the guide rail in general. As a result, all the possible vibrations of the design will be damped out: from low to high frequency, both from the impact of single modules and their airflow, and under the action of the wind, including the gusty one, etc.

In addition, due to its inertness and high stiffness of high-speed string-rail track caused both by string tension and the flexural rigidity of the rail itself, the dynamic amplitude of structure oscillations will be slightly different from the static one.

Then the Chapter describes in detail the composite structure of the guide rail at the string transport system, the design and purpose of using strings as the elements accepting the tension force that ensures their integrity and connection between them. And we have already briefly illustrated it in one of the previous releases.

Despite the fact that while writing the monograph, there has already been a considerable experience of researching the stressed condition of separate elements of the composite structure discussed above, for strength study of SkyWay guide rail the author points out the need to build a model that takes into account the complex of mechanical properties of all components, adhesive interaction in the connection "head - casing", the contact loading of the head and pre-tensioning of strings.

As you know, currently the center of testing - SkyWay EcoTechnoPark - has already been created, but we will continue to talk about it and specifics of redetermined research involving modern matrix methods to calculate elastic systems with modern approach required for designing SkyWay rolling stock, in the next release on the second part of Chapter 3.