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Date submitted2024-05-11
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Date accepted2025-01-28
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Date published2025-03-21
Research and development of technology for the construction of snow airfields for accommodating wheeled aircraft in Antarctica
- Authors:
- Sergey P. Polyakov
- Sergey V. Popov
Construction of a new wintering complex at the Antarctic Vostok Station required prompt delivery of builders and mechanics to Progress Station to move them further to the work area. To solve this major logistical issue, a new landing site, later named Zenit, certified for accommodating heavy wheeled aircraft, was prepared in the Progress Station area from March to August 2022. Its snow pavement slab with a total area of 350 thousand m2 is from 100 to 120 cm high. It was made by applying snow layers with their subsequent compaction by a specially designed compaction platform for snow airfields suitable for heavy wheeled aircraft. As a result, the pavement has a surface hardness of at least 1 MPa. The layer from 30 to 60 cm has a hardness of at least 0.8 MPa, and the bottom layer at least 0.6 MPa. The first Il-76TD-90VD aircraft of the Russian company Volga-Dnepr was accommodated to the new runway on 7 November 2022. The aircraft landed in normal mode. The depth of the chassis wheels track after landing did not exceed 3 cm. The research provided in-depth understanding of the mechanisms for forming the supporting base of the runway from snow and ice in Antarctica. The experience gained can be used to solve similar issues in the Far North.
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Date submitted1951-07-18
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Date accepted1951-09-27
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Date published1952-12-23
Asymmetric bending of annular plate by moment
- Authors:
- L. S. Burshtein
Asymmetric bending of the ring plate is encountered when developing designs of couplings, compensators and various corrugated elements included in the overall system to increase its elasticity. The efficiency of such plates is determined not only by their dimensions (internal and external diameters, wall thickness), but also depends to a large extent on the rigidity of the elements to which they are directly adjacent and the design of the transition from the plate to the element conjugated with it. In some cases, the method of fixing the plate along the outer contour comes closest to rigid embedment, in others it can be considered equivalent to hinged support. The main value characterizing the elasticity of the plate is the angle of rotation of the inner contour to which the external bending moment is applied. This value for the scheme with hinged support, all other things being equal, is significantly greater than for the scheme with rigid embedment. However, along with this, there is an unfavorable factor associated with a significant increase in stresses in the scheme with hinged support compared to rigid embedment. The correct solution to the problem comes down to selecting the dimensions of the elastic element in such a way as to obtain the largest angle of rotation of the internal contour at stresses not exceeding the permissible ones. For this purpose, it would be necessary to take into account the degree of rigidity of the fastening and make the calculation as for the scheme with elastic fixing.