# Material Thickness and Bolt Shear Strength

Daniel Louis
I am wondering why the material thickness is not factored into calculating bolt shear strength in a joint. I know that it is used when calculating the strength of the material itself and its susceptibility to deformation and tear out but why not the bolt? When you cut a piece of cheese you use a knife because of its small surface area and large force so would a thinner and stronger material cause a bolt to shear at a lower pressure? Does it have something to do with the elasticity of the material and the materials ability to actually increase surface area contact with a thicker material?

Thank you!

haruspex
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I am wondering why the material thickness is not factored into calculating bolt shear strength in a joint. I know that it is used when calculating the strength of the material itself and its susceptibility to deformation and tear out but why not the bolt? When you cut a piece of cheese you use a knife because of its small surface area and large force so would a thinner and stronger material cause a bolt to shear at a lower pressure? Does it have something to do with the elasticity of the material and the materials ability to actually increase surface area contact with a thicker material?

Thank you!
Cutting with a sharp edge is not through shear. The wedging pulls the material apart, so would be more related to the tensile strength of the bolt (but somewhat complicated through crack propagation matters). In practice, most materials bolted together are probably either too thick or (compared with the bolt) too soft for this to be a concern.

Daniel Louis
Daniel Louis
Cutting with a sharp edge is not through shear. The wedging pulls the material apart, so would be more related to the tensile strength of the bolt (but somewhat complicated through crack propagation matters). In practice, most materials bolted together are probably either too thick or (compared with the bolt) too soft for this to be a concern.
Thank you for the response!