“…Over the years of independence in the Republic of Uzbekistan, in order to create a unified railway network of the country, a number of major projects have been implemented to build tracks and enhance the infrastructure of railway transport, equip the rolling stock fleet with new locomotives and wagons with improved technical and economic characteristics. For example, in 1994-2001 a new railway line "Navoi -Uchkuduk -Sultanuizdag -Nukus" was built; in 2003-2007 "Tashguzar -Boysun -Kumkurgan" railway was built; in 2011-2013 "Yangier Novaya -Dashtabad", "Gallaaral -Bulungur" and "Dashtabad -Jizzakh" railway sections were built; in 2013-2016 a project for the construction of a new Angren-Pap railway was implemented]; in 2017 the electrification of the "Karshi -Termez" sections was completed and "Pap -Kokand -Andijan", the "Bukhara -Misken" railway was built [6][7][8][9]. During the construction of new railways, especially in mountainous areas of the republic, where the slope of the track exceeds 12.5 ‰ (for example, on the Angren-Pap railway section, the slope of the track reaches up to 27 ‰, on the Tashguzar-Baysun-Kumkurgan line, the slope of the track is from 12 ‰ to 18.5 ‰), important tasks when ensuring the safety of rolling stock movement, the selection of the optimal traction of the locomotive for the operation of trains, the determination of the longitudinal-dynamic coupling forces of wagons and locomotives arising during ascent and descent, as well as checking the critical mass norms and conditions for passing trains.…”