POLYTECHNIC BULLETIN
Series Engeneering Studies
ISSN 2520-2227

Abdullo Mamadamon

Annotation:

Safety, mechanical reliability, and environmental efficiency of road transport in mountainous conditions are traditionally studied as isolated problems with separate regulatory frameworks. With the large-scale electrification of the vehicle fleet, this division loses its scientific validity because a single physical mechanism—the degree of energy storage saturation during regenerative braking—simultaneously determines the thermal load of friction brakes, component reliability, and non-exhaust particulate emissions. This study synthesizes four interrelated directions within a unified concept, where the critical length of regeneration exhaustion serves as an interdisciplinary cross-cutting parameter. Based on official traffic accident statistics in the Republic of Tajikistan for 2016–2025, recording a 50.6% increase in fatalities alongside stable accident rates, as well as field tests on 117 tires, it is strictly proven that for a loaded heavy truck, battery capacity is exhausted after 6.9–13.8 km of a descent. Паёми политехникӣ. Once regeneration ceases, the entire braking load shifts to friction mechanisms not designed for such continuous stress. This threshold directly determines the ratio of non-exhaust emissions from electric vehicles to internal combustion engine emissions. The proposed invariant longitudinal dynamics model enables the scientific optimization and placement of charging infrastructure based on the minimum charge level profile.

Keywords: mountain road transport; operational safety; reliability; well-to-wheel emissions; regenerative braking; electric vehicle; charging infrastructure; Republic of Tajikistan.