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Analysis tools for 2-span continuous glulam beam with cantilever span at one end? 1

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AELLC

Structural
Mar 4, 2011
1,339
I don't have anything available to design this, it has uniform loads that vary in intensity along its spans and a few concentrated loads. The concentrated load at the cantilever end is large and worrisome.

I have my own Excel which can do a 2-span continuous beam, but this has the cantilever span in addition at one end.

I have used STRUDL and similar major programs in the past but don't have the time to re-learn something complex or the resources.

Is there anything user-friendly with minimal learning effort, and less than $300 in cost? Is Enercalc capable of this?

If not, I will patch this together by using my Excel and superimposing the 2-span continuous and cantilever conditions as an approximate analysis.
 
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You were correct, the 12'-1" is the controlling factor for C sub L. I came up with 0.84, and that didn't overstress the beam in bending. I also could reduce the live loads some more if I wish because the beam supports both floor and roof loads.
 
Strukter,

There is something I noticed in the moment diagram graph in Beamanal - other than the 300' span is not shown correctly in proportion to the 21.2 and 12.1 spans - the moment at 4' to the right of support 3 is 1,950 ft-lbs instead of zero, and that must be a result of the 300' span not quite modeling this correctly.

If I "tilt" the moment diagram down to get M=0 at the 4', then my moment just to the left of support 3 goes from -26,970 ft-lbs to -28,920 ft-lbs, which isn't very much but should be taken into account.
 
You are correct.

I then input 10,000' instead of 300', and that brought the moment at the end of the 4' cantilever to near zero, but it distorted the graphs.

So I suggest to use the very large span to get the correct values, and the smaller span to view the graphs if desired.

 
Nice simple thread. I like the 300' (errr. 10,000' span)

Manipulating software should be an engineer's second best friend. Can you name the first?

 
I use woodwork to do the wood design. The cost is $295. I think Enercalc can do it too. You can try the demo version quickly.
 
Well, when I found out Beamanal could do the analysis at no cost, it became easy for me to modify my Excel to design the beam, therefore there now would be no point in using Enercalc or Woodworks.

At first I thought Beamanal couldn't do this analysis because of the cantilever with heavy concentrated load at cantilever end, but such is not the case.
 
Not to derail the thread, but I was wondering if the forums has any options where engineers could possibly share their engineered EXcel spread sheets?

A separate forum for that might be VERY interesting.

I have several cool ones from checking Lag Screws to built up shapes of light gauge framing, to combined bending and compression for drag Wide flanges that are composite or non-composite, etc...

 
TDI,

I also was very interested, but so many threw a wet blanket on this idea, complaining the Excel spreadsheets had errors, etc.
 
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