Loads transported by road, rail or sea are all subject to external forces due acceleration, deceleration and changes of direction such as taking corners.
These forces will try to move the unit load in the same direction as the force. For example, the load on an accelerating lorry will be subjected to a force towards the rear of the lorry and may fall off if not secured.
The load will be subjected to forces during transport which will try to move it forwards, backwards, sidewards and, in some extreme situations, vertically.
Movement during Sea transport
G-forces
The movement of a load is generally caused by 2 forces: acceleration and deceleration.
G-forces on the load are the result of movement of carriers during acceleration deceleration, taking curves or through the movements of a ship due to the influence of waves.
Under influence of these forces, the load will want to move in the direction of the G-force.
G-forces differ depending on the direction of movement.
way of transport
Forwards
Backwards
Sideways
Road transport
0.8
0.5
0.5
Sea transport
1
1
1
Rail transport
1-4
1-4
0.5
0,5 Gsidewaysaccelerationin road transportcorresponds to a tilt of 30°.
The G-force by rail can reach a value of to 4-G, by shunting the railway wagons.
Friction
Friction between the load and the carrier floor also has it’s influence on movement of the load. Every load/carrier floor combination (e.g. wood on wood or metal on wood).
has a different friction value. This value is an indication of how easy a load can start to move.
For example: The friction per material combination is shown as a friction coefficient (µ). A value of 1 shows no movement, and value 0 is free movement without any frictional force.
