Lo svio. Cento e più anni di un problema complesso. I deragliatori

The experimental researches on derailments made in Europe in the last century with the use of special vehicles are examined. The results qualitatively confirm the more advanced theories of Heumann and Chartet but they also pose new problems related to the track deformability and to the complexity of tribological phenomena involved in derailments. This requires the adoption of precautionary limits for H and Y/Q independent from theoretical models. These limits can be found in the technical legislation currently in force. A recent resumption of experimentation, based on the use of advanced computational and measurement technologies, produced enlightening results and on the one hand confirmed already known prolems and on the other hand highlighted unforeseen dynamic phenomena at high speeds.