Stabalize a frame with straps

epheterson

Hey all,
I'm working on an experiment and we have a frame which will be exposed to loads in all directions. I'm trying to analyze how to best secure it and am having trouble considering the 3D analysis, while the 2D analysis seems rather simple to me. I was informed the 2D analysis is insufficient, though, and must consider 3D. I believe when I enter the 3rd dimension I introduce a statically indeterminate system.
I've attached my FBD's and initial 2D equations, could you please guide me in making these 3D. The lateral 2G load especially needs to be considered in 3D. I've created the vectors necessary, but can't find a valid solution. My moment equation was about the CG and included only these two cables, when I tried to solve with my TI-89 titanium it said false .

r4_=[39,12,3] inches (vector from CG to T4 connection)
r5_=[-21,12,3] inches (vector from CG to T5 connection)
T4_=T4*[-.98,.098,-.172]
T5_=T5*[.98,.098,-.172]

I'll be putting this together in Abaqus while waiting for your comments. Halp!

Attached Thumbnails

 

Attached Files

Floor Attachment Analysis.pdf (1.35 MB, 7 views)

epheterson

No takers? It seems like a simple 3D statics problem, I just haven't had statics in a while.

epheterson

Y'all are lame.

epheterson

Dude I need numbers, and 4 is not enough.

epheterson

rcgldr, I don't like you. You don't read. I had already figured out how I was attaching it, and needed magnitudes of the tension in the cables. Both of your posts were useless to me.

The correct answer was to simply add the third direction to my moment equation, I'm done now.

Mod, please close this forum.

rcgldr

Sorry, I couldn't download the pdf file the first time I tried, so I was just guessing at what you wanted since no one else responded. I tried and again and was able to see the pdf file, so I understand you question now, but you've already solved it.

epheterson

It's cool I appreciate your comments. I've never seen this board so mute with such a simple question. Probably a TL;DR situation.