Details under https://en.wikipedia.org/wiki/Montech_water_slope

Found them after hearing them mentioned in the video linked in this comment to The Fonserannes Water Slope Tractor. Built in 1983 and abandoned in 2001 this giant trough on 18 wheels was meant to replace a row of staircase locks and carry boats up a hilside. It never ran right and was highly unreliable (which is kinda their successor) here in r/WeirdWheels.

They look like originally being railroad diesel locomotives to me. And they remind of me that Russian diesel locomotive from r/MudRunner. ;-)