Lateral Force Generated From Cornering Speed
Tipping angles mentioned above are all well and good, but what makes the float tip in the first place?
Assuming we are driving on a road with minimal camber, the main factor influencing the tendency to tip, is lateral force.
Here is the lateral force acting on the 20 t boom as the float travels around a corner.
This Centrifugal Force is defined by the equation:
Fcentrifugal = mass x velocity2 / radius
If we take a 300m radius turn and a speed of 80kph (22.2ms-1) we get
Fcentrifugal = 20,000 x 22.22 / 300 = 33kN
Lowering the speed to 60kph (16.67ms-1)
Fcentrifugal = 20,000 x 16.672 / 300 = 19kN
Effect of Velocity
As velocity is squared in the equation, reducing the speed by only 25% has resulted in a 42% reduction in centrifugal force acting on our boom.
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