Pmax=80 kips and Pmin=20 kips. Assume the load is equally distributed to all the bolts. It has been determined to use ½ in-13 UNC grade 8 bolts. Determine the fatigue factor of safety using the Goodman criteria.

Respuesta :

Explanation:

Minimum Proof strength (sp) = 120 kpi

minimum tensile strength (sat) = 150 kpi

Now, calculate the load per each using the equation

                            [tex]p=\frac{80}{N} \mathrm{ki}[/tex]

calculate the preload for non permanent connection

[tex]F=0.75 \mathrm{sp} \mathrm{At}[/tex]

[tex]F=0.75 \times 120 \times 0.1419[/tex]

[tex]F=2.77 kip[/tex]

Calculate the stiffness constant for the assenbly

[tex]c=\frac{k p}{k_{p}+k_{m}}[/tex]

Substitute

[tex]c=\frac{4 \times 10^{6}}{\left(4 \times 10^{6}\right)+\left(12 \times 10^{6}\right)}[/tex]

c=0.25