The question is to draw the shear and moment diagram for this frame structure.(adsbygoogle = window.adsbygoogle || []).push({});

I think I can do the diagram part alright, but I'm confused as to how I can draw the FBDs for this structure. What I'm thinking is to split into two members, AB and BC.

For member AB, I know that there's two reaction forces at A, and (I think) also two reaction forces at B? Like so:

I'm pretty sure that the FBD for member AB I got right. However, I'm unsure of how to draw the FBD for member BC. How am I supposed to orient the reaction forces at C? I tried looking for examples in my textbook similar to this case but couldn't find any. Here's my attempt:

Is this right? I tried solve for my unknown forces from these two FBDs and while member AB seemed fine, I swear I am doing something wrong for member BC. The answer key listed the max shear force to be 11.7, which I achieved in member AB. But when I solved for shear forces in member BC, I got a shear force exceeding that of 11.7, so that means I must have done something wrong. I have no idea where though.

Please advise, thank you.

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# Homework Help: Drawing the Forces for this Structure?

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