Practice Problem 6-2(a)

Practice Problem 6-2 (a)

Given: In the Midwest (e.g., North Dakota), hay bales are often baled into round bales. A typical hay bale can have a radius of 4 ft. The hay bales are held together using a steel baling wire with a 1/16" diameter and Young's modulus of E = 25 Msi.

Req'd:
What is the maximum tensile strain in the baling wire, e_max [%]?

Solution: Strain due to bending is given by:

e = -y/R

Where y = -(t/2) = -1/32 in. and R = 4 ft = 48 in. Thus:

e = (1/32 in)/(48 in) = 0.000651 = 0.065 %