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Pre-cast Concrete Analysis Question

Pre-cast Concrete Analysis Question

Pre-cast Concrete Analysis Question

(OP)
I have been asked to look into the design of some pre-cast concrete panels.  The panels are 30' long x 4'-5" wide with supports of various types (pinned x y z and pinned z only) at random locations.  This makes the analysis by hand pretty rough.  I have a set of hand calculations that estimates the forces in the panel but I would also like to run a case using FEA and compare the two.

I have taken classes in FEA but we never discussed how to use the output information to design concrete members (this class was given in the Mechanical Engineering Department so they were not worried about concrete).  Under my output I have MX and MZ (amongst 22 other options).  Are these the forces I should use to design my reinforcing in X and Y direction?
 

RE: Pre-cast Concrete Analysis Question

The answer to your question is Yes. Now you have bending moment and shear force in both directions, it is a question of designing the reinforcement and checking the adequacy of the section using the Code of Practice on Reinforced Concrete.

You said you have already done some hand calculations. So it is important to check the computer results against hand calculation results first.

RE: Pre-cast Concrete Analysis Question

Steelpe:

Contrary to what normm said you need to do some checking on definitions for the specific code you are using....to clarify my point consider:

a beam with the length of the beam being defined as the "x" axis....if the moment output is a vector then the results output as MX are in fact the twisting moment for the beam rather than a bending moment (and a similar situation exists for the other moments and forces).....thus the need to understand the specific output of the code you are using...

Ed.R.

RE: Pre-cast Concrete Analysis Question

(OP)
Thank you for your responses,

I should note that I meant to write MY and not MZ in the above post (sorry about that).

I have looked at the results and they match how I believe the moments would be distributed in the member (see attached).  As stated above, the structure is a pre-cast panel subjected to a uniform wind load together with wind from the windows above and below the panel (these loads were modeled as a nodal point load).  I used concrete plate elements to mimic the panel.
 

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