Abstract
This article examines the factors influencing the reduction of tire–road adhesion under winter conditions, with particular emphasis on vehicle speed, snow and ice formations, and pavement surface characteristics. The study aims to determine how vehicle speed and pavement macrotexture affect the coefficient of adhesion on winter road surfaces. Computational methods were applied to establish the relationship between vehicle speed and the coefficient of adhesion. The analysis considered different types of snow and ice formations, as well as the influence of crushed stone size and shape on pavement texture and macro-roughness. The findings indicate that as vehicle speed increases, the coefficient of adhesion decreases, especially on surfaces affected by icing or snow accumulation. This reduction is associated with shorter tire–road contact time and increased dynamic loads, which weaken tread interaction with surface irregularities. The study also confirms that the size and shape of mineral aggregates significantly influence pavement macro-roughness. Higher macro-roughness improves drainage capacity, reducing water accumulation and the likelihood of ice formation. However, excessive crushed stone content may accelerate pavement wear and lead to partial deterioration of the surface layer, negatively affecting adhesion. Additionally, surface depressions can accumulate moisture that freezes at subzero temperatures, forming initial icing zones that expand under traffic loads.Vehicle speed and pavement macrotexture are critical factors affecting skid resistance in winter conditions. Proper selection of aggregate characteristics and effective winter maintenance strategies are essential to minimize slipperiness and enhance road safety.