main determining factors in the construction of roads is the traffic of vehicles, speed limits and axial load.Depending on the width of the projected road and clothes.Categories of roads established by all of the following indicators: the actual and reduced traffic volume, the number of lanes, speed, bandwidth, the width of the median width fortification edge band, the width of the roadbed, the maximum longitudinal gradient, curve radius in turn.Major categories of roads in Russia - I, II, III, IV, V.
I and II road categories are assigned to sections with major type of coating, which include various road having from one to several bands in each direction.They are designed for speeds up to 120 km / h (1a - up to 150 km / h), it can move on vehicles with axle load up to 10 tons, they have wide bandwidth (3,75m), the maximum slope is limited to 3-4%, the radiiturns up to 1200 m.
wide shoulder and dividing strips (for category I roads) provide security and bandwidth required.Road maintenance this category includes a wide range of activities, in particular for the categories I and II roads are cleaned of snow, cleaning the ice, as the movement is carried out on them all year round.
for road category III, where there is less traffic, improved settling lightweight coating.They allowed bandwidths of up to 3.5 m and a turning radius - 600 m, they can reach a maximum slope of 5%.But at the same sites for category III vehicles can move with axial loading to 10 tons. Current speed limits on them - no more than 100 km / h, the number of lanes in each direction - no more than two.
to the IV category includes paved roads, but it can not be improvements (a coating of gravel, rubble).The width of the lanes are not more than 3 m, the maximum longitudinal slopes may reach 6%, the minimum turning radius of 250m.The maximum axle load - 6 m, in the winter they need to be cleaned, but it can be left on the coating layer of ice and snow.
If the road does not have enhanced coverage in the spring they may impose restrictions on the movement of certain vehicles carrying capacity.The reason for this lies in the fact that the spring due to the high moisture roadway decreases its bearing capacity and at a selected axial load may occur deformation of the pavement.If the restriction is not introduced, the spring on such roads should move cautiously, given the fact that due to nervousness and the resulting cracks can vary constantly rolling friction, which complicates the control of the machine.
of V category includes roads that do not have hard surface (paved for normal ground).To increase the stability of the top layer of the surface is sometimes treated with special bonding additives.Between bad roads or during heavy snowfall on them allowed the termination of movement.They are, as a rule, only one lane, which at design speed is less than 60 km / h.
