The paper presents the results of the author’s field investigation in CWR track subjected to generated imperfection and applied static forces. During field tests the measurement system Pontos is used. In the railway track the phenomenon of unsupported sleepers (i.e. effect of hanging sleeper) is simulated and analyzed. The used author’s method, making use from the measurement in the loaded track, allows for the tracking changes in railway track’s work and its behavior. The obtained results significantly change the deflections and stresses in the railway track structure (especially in characteristic cross-sections: the beginning/end and the middle of the irregularity). The measurements and analyses presented in the paper show a significant changes the behavior of the loaded elements of the railway track structure (in the case of sleeper deflections even their twice increase). In the paper on the basis of simulated irregularities (contact loss between the track and ballast along its length), the measurements of rail and sleeper deflections, as well as the force transferred from the rail to the sleeper in a real jointless track are taken. For the maximum measured force, analyses are carried out to determine the change in static sleeper deflection along its length due to the contact loss between the sleeper and ballast (areas of lack of support in the under rail’s cross-section). The obtained additional sleeper’s deflections increase for the front of sleeper by 23,4%, for the rail’s cross-section by 23% and for the middle of the sleeper by 22,7%.