UST: News

Double Doctor of technical Sciences, a world-renowned scientist Mikhail Orlov visited the President of the SkyWay Group of Companies Anatoly Yunitskiy, with whom they share not only a business relationship but also a long-standing friendship. In a private conversation the two scientists touched upon various subjects, many of which have a direct relation to SkyWay.

The information service of the SkyWay Group of Companies publishes a snippet of the conversation from which you may learn how a track structure will behave at low temperatures.

Translation of the video:

professor, Doctor of Engineering Science on two specialities (computer engineering and systems of automated designing);

co-founder and scientific supervisor at Modern TRIZ Academy, author and co-author of 220 publications including 12 textbooks and monographs, more than 50 personal inventions (Author?s Certificates and patents) and more than 200 inventions by custom orders;

experience of creating and heading 6 companies established at different time for the last 23 years;

performing development of theory, managing development of products and technologies, promotion of global partnership and expansion of Modern TRIZ.

Anatoly Yunitskiy:

Author and General designer of Unitsky String Technologies;

Manager of two UN projects;

Member of the USSR Federation of Cosmonautics;

Author of more than 140 inventions;

Author of 18 monographs and above 200 scientific publications;

Education:

railway engineer;
patent law and inventive act;
designing of high-rise buildings and infrastructure.

General director - General designer of SkyWay Technologies Co.;

Awards:

two golden medals of all-Russian Exhibition center;
two "Golden chariot" in nomination "Project of the year in transport industry";
three Golden quality marks "Russian brand";
honorary title "Knight of science and arts";
30 diplomas of international exhibitions.

— I would like you to consult me and remind one thing. People often ask about it. Certainly, I read what you wrote. I understand and accept it. However, people want to know it exactly since they have some concerns. Perhaps, these are the last concerns. It is referred to temperatures. Low temperatures. You know, Europe is not Africa. In winter temperatures here may be low.

— I cannot answer briefly. If I say it will not break, they wouldn't believe. It should be explained. A string in the structure may break on two reasons. Firstly, improper types of steel. There are types of steel that do not withstand low temperatures. Naturally, we do not use these types. For the string we normally use steel 65 or 80 types. It is a low-carbon steel and it is not fragile at frost. It withstands minus 60-70 °C. It withstands it without becoming fragile. Therefore, the structure would not brake on that reason, because it will not become fragile. There is a second reason. Since our structure is continuous (uncut), it does not change its length, it does not shrink at low temperature. On the contrary, the structure begins to compress at low temperature, but the anchor support holds it, therefore the length is unchangeable. Tension begins to grow in the material. The figures are known from the theory of strength of materials.

— I know it and I tell them I know. They say, "No, you prove it".

— The figures are known. It is known that if we multiply elasticity modulus of steel by the linear expansion coefficient, we'll get the value that will characterize by how much the tension will change at temperature change by 1 degree. Therefore, at a drop of temperature by 1 degree, the tension of a steel structure, which is predeformed at the ends, will change by 25 kg/sq. cm. That's why if the temperature difference is 100 °C, suppose from +50 to -50 totaling 100 °C, the tension change in the continuous structure predeformed at the ends will be 2,500 kg/sq. cm at 100 °C temperature difference. It is a substantial temperature difference. Therefore, if we use weak types of steel, for example, steel 3, which is used for nails, naturally it would break. However, for the string we use steel with breaking strength not lower than 18,000 kg/sq. cm. This is like in the high-strength reinforcement wire; this is like in the reinforcement strand. There are also types with 20,000 kg/sq. cm, even 24,000 - we have such samples. Therefore, the structure will have pre-stressing, for example, 8,000 kg/sq. cm. We pre-stress it at maximal temperature, say, +50 °C. Then the temperature drop will add 2,500, it will be 10,500. Then the load will add up to 1,000 kg/sq. cm. We have such a unique structure that loading does not affect greatly the tensioned condition. We add it and get 11,500 kg/sq. cm. Next, there is a wind load. It will not exceed 1,000. The total will be about 12,500 kg/sq. cm. These are acceptable tensions in high-strength reinforcement on suspended cable bridges. This is the state of tension that is allowed by standards. We have a strength reserve of 5,000 to 6,000 kg/sq. cm. This is quite a large reserve, because usual reinforcement has the strength of 3,000 kg/sq. cm and in high-strength reinforcement it is 5,000 kg/sq. cm. Just strength, but we have a reserve of strength. Therefore, the structure will not break at low temperatures.

— This is a very helpful information. Thank you very much. Actually, this was the purpose of my visit here.