5.1
Load assumptions
The considerations and investigations
into load assumptions have shown that it is inadmissible to interpret the
previously conventional values of 0.8 g forward and in each case 0.5 g rearward
and to the sides directly as vehicle accelerations in the form of braking
deceleration, starting up acceleration or centrifugal force of cornering. In
particular, direct reference to maximum forces which can be transferred by the
vehicle tires is inadequate. The forces acting on the cargo are significantly
boosted by inclination of the loading area (pitching and rolling angles) and by
tangential inertial forces from superimposed pitching and rolling oscillations.
At the same time, the normal force which is of importance to friction and
inherent stableness of cargo units is reduced, despite always being inserted in
conventional securing balances with the full weight of the units.
These findings may mean, for forward load
assumptions, that for a vehicle equipped with tires and a braking system
capable of delivering braking deceleration of 0.8 g, the acceleration assumed
for cargo securing must be 1.0 g.
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