3D Equillibrium Statics Problem - Reaction Forces/Moments

AI Thread Summary
The discussion revolves around determining the reaction forces and moments in a rigid body, specifically a beam fixed at one end with vertical and horizontal forces applied. The user is seeking assistance with a static equilibrium problem involving a roller support and an angled rod. Key advice includes summing forces in the x, y, and z directions and equating them to zero, as well as choosing strategic points to sum moments. The user expresses uncertainty about the accuracy of their moment calculations despite feeling confident about the forces. The conversation highlights the complexities of analyzing a 3D system and the importance of using Cartesian vector notation for clarity.
mjgarrin
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Hello, it has been quite some time since my statics class, and I am having a problem determining the reaction forces and moments in a rigid body. I have included a sketch of my problem, and I am hoping someone can help guide me to a solution. I apologize if the sketch is a bit crude.I have a beam that is fixed at one end. On the opposite end, there is a vertical force acting directly on the beam (F1 = 1,000 lbf), and a horizontal force acting on a bar attached to the beam (F2 = 250 lbf).

The beam is supported by a roller, and has a reaction load in the vertical directly only, located 30 inches from the end of the beam.

The beam is also supported by a rod, located 12 inches from the fixed support, and the rod is at an 18 degree angle.

I am trying to find the reaction Forces as well as the Moments to show this scenario in static equilibrium.

Thank you.
 

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Can you describe the application? 1000 pounds is a lot of force...
 
I just gave made up numbers just to get an idea how to solve such a problem. I agree, the forces may not translate well to the size of the beam. Any force would work.
 
Sum forces in the x, y, and z directions and equate to zero. Also choose a convenient point(s) to sum moments around and equate to zero. Start here and let's see how many unknowns you have. Also since it's a 3D system I would recommend using cartesian vector notation.
 
I think the added fixed rod is causing me some issues. I tried summing the forces and moments, and got the following in the attached sketch. I think the forces are right, but I am not sure the moments are accurate...
 

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