Received 11.08.2021
Revised 08.11.2021
Accepted 10.12.2021
Retrieved from Iss. 110, 2021
Pages 35 -43
Abstract
In various static stamp tests methods, both foreign and Ukrainian, it is foreseen to use a different number of sensors for stamp settlement measuring. Austrian method with three displacement sensors allows to reveal the stamp warping while loading, but it is unclear how to determine the settlement in the stamp center, when the sensor readings at the moment of warping will be completely different. The German method with a single displacement sensor is much simpler, but does not consider the stamp warping. The use of Ukrainian methodology is not appropriate at all, because two displacement sensors do not allow to observe the stamp warping. The article is focused on mathematical model for the displacement of stamp points in road structures static testing development with theoretical justification of necessary and sufficient number of sensors for stamp settlement measuring. Initially, the stamp displacement under warping in a flat deformed condition is considered as a rotation on a certain angle α and a parallel transfer. It has been established that in this case, the stamp settlement with enough accuracy for engineering practice can be measured with a single displacement sensor installed in the stamp center. In fact, the stamp can rotate not only around the axis Oy, but also around the Ox axis. Therefore, a separate mathematical model is constructed and describes the process of stamp displacement while it’s warping in a volumetric deformed condition. The developed mathematical model provides an opportunity to determine the settlement in the stamp center, necessary for the modulus of elasticity calculation or modulus of deformation in the case when the stamp at the warping moment will rotate both around the axis Oy and around the Ox axis, and the rotation angles α and β will be significant.
Keywords:
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