Question

A civil engineer designs a wheelchair accessible ramp next to a set of steps leading up to a building. The height from the ground to the top of the stairs is 3ft. Based on ADA codes, the slope must be 1:12 or less. (Slope is equal to the rise of the ramp divided by the run of the ramp.) What is the IMA of this ramp if the engineer uses a slope of 1:12?

Answer 1

Answer: IMA = 12.042

Explanation:

Given that;

Height from the ground h is 3 ft

Slope of ramp s is 1:12

Horizontal length of the ramp x will be 3 × 12 = 36 ft

Now to get the IMA ( ideal mechanical advantage,)

IMA = length of the ramp over / height of the ramp

IMA = (√( 36² + 3²)) / 3

IMA = (√ 1305 ) / 3

IMA = 36.124 / 3

IMA = 12.042