If we consider the general two dimensional state of stress, we see three components of stress.  There are two normal stresses and one shear stress.

 

 

 

 

 

 

 

 

 

 

A normal stress may be tensile or compressive.  It is important to note the difference by either writing ( T ) or ( C ) after the stress magnitude or putting a sign on the magnitude with tension being positive and compression being negative.  Do not use both conventions together since a negative sign negates the word.  In other words, -10 ksi ( C ) is that same as +10 ksi ( T ).

 

Later in the semester, we will be concerned about the direction of a shear stress, but for now we will only calculate a magnitude without a sign.  If the author puts a sign on shear stress in an example or solution at this point, I want you to ignore it.

 

Let’s consider a simple example of each type of stress.

 

The Axially Loaded Bar

 

 

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