Loading, dimensions, masses and axle loads
Domain focus
This section covers teret, dimenzije and mase: maximum gross mass, axle loads, payload calculation, load distribution, securing and oversize/overweight permits.
Core rules
- EU/road-transport limits commonly used for international CE operation include 40 t gross mass for a five- or six-axle combination, 2.55 m width (2.60 m for certain refrigerated vehicles), 4.0 m height, 16.5 m for an articulated vehicle and 18.75 m for a road train. National rules can differ, so check Croatian limits and any permit.
- Axle limits matter as much as gross mass: a single axle is commonly limited to 10 t and a drive axle to 11.5 t. Overloading one axle is a defect even if gross mass is legal.
- Distribute the load low and centred. A heavy load at the rear can overload the trailer axle and reduce steering-axle grip; a heavy load forward can overload the tractor's steering axle.
- Secure cargo against forward, rearward and sideways movement using rated lashings, blocking or friction mats. Check the load after the first kilometres.
Worked example
A tractor unit has a tare mass of 9,000 kg and the semitrailer 7,000 kg. The combination's gross limit is 40,000 kg, so the simple payload is 40,000 - 9,000 - 7,000 = 24,000 kg. If the drive axle would then exceed 11,500 kg, the load must be moved or reduced even though 24,000 kg is below the gross limit. The correct answer is therefore not just 24 t; axle limits must be checked.
Traps
Calculating payload only from gross mass; ignoring the fifth-wheel load; using unrated straps; and assuming an oversize permit covers weight as well as dimensions.