In this paper, a rail joint model consisting of three Euler-Bernoulli beams connected via a Winkler foundation is proposed in order to point out the influence of the joint gap length upon the stiffness of the rail joint. Starting from the experimental results aiming the stiffness of the rail joint, the Winkler foundation stiffness of the model has been calculated. Using the proposed model, it is shown that the stiffness of the rail joint of the 49 rail can decreases up to 10 % when the joint gap length increases from 0 to 20 mm.
unsteady lubrication. Monograph, Published by Wierzcholski Krzysztof, Gdańsk University of Technology, pp. 1-172, Gdańsk 2006.  Wierzcholski, K., The method of solutions for hydrodynamic lubrication by synovial fluid flow in human jointgap , Control and Cybernetics, Vol. 31, No. 1, pp. 91-116, 2002.
the current research.
Measurements were made to determine how the temperature and humidity inside the structure change
after the renovation. At measurement locations 1 and 4, a much smaller delay can be observed in the
change of internal temperature, presumably, there is a jointgap in the lower skin. At present, there is
no problem from this due to the low internal moisture load, but the phenomenon observed at two out
of the four examined points indicates that panel gap problems are common, therefore in the future,
the convective moisture load must