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If we examine the $example-1$ of cantilever beam 1 above, there will be shear force $Ft$ and moment $M$ that will keep the beam in balance statically. However, when we examine the strength, that is, the states of the objects under force, we see that tensile and compressive stresses occur in the cantilever beam, as in $example-2.$ Could you please refer to the following question regarding the tensile and compressive forces in $example-2$ above?

  • Do tensile and compressive forces always have to be equal to each other when we take a section from where the beam meets the column? If it is not equal, will the horizontal net force not work to move the beam?
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  • $\begingroup$ If they do not equal, then you are not is a Static situation and your beam will be accelerating. $\endgroup$
    – Forward Ed
    Jun 22, 2023 at 23:32

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Tensile and compressive stresses originated due to a bending moment will always be equal and cancel each other when integrated through the whole cross section. This is because a force applied vertically at the end of the beam won't alter its translational equilibrium in the horizontal direction. Of course there's also shear stress on that cross section, and that will originate the vertical reaction force.

A different case is that where the force that causes bending also causes a tensile stress:

Here the tensile and compressive stresses are not equal, because the pulling force is positioned with an offset with respect to the neutral axis. When integrated, they result in the F force that is pulling the beam.

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    $\begingroup$ Do you need clarification about something I wrote? $\endgroup$ Jun 22, 2023 at 18:07
  • $\begingroup$ I started to share my new questions, new questions will come during the day, I'm doing a thesis work on static calculations of a tall building, the questions will continue to be posted for a day or two, thank you. You can see the question I asked on the link. engineering.stackexchange.com/questions/55612/… $\endgroup$ Jun 27, 2023 at 11:31
  • $\begingroup$ Can you take a look at the new question, there is no commented answer yet. @RocketScience $\endgroup$ Jun 28, 2023 at 7:17
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    $\begingroup$ I am on vacation for a few days, when I'll get back I'll take a look, but don't worry, here there are a lot of good people that know even more than me. $\endgroup$ Jun 28, 2023 at 8:52
  • $\begingroup$ thank you, i'm doing postgraduate studies so i didn't have much time. No response from anyone yet, so I wanted to write to you. @RocketScience $\endgroup$ Jun 28, 2023 at 9:29

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