Beam with uniform loading supported at 4 corners

[nmk15]

Hi
I have a wood beam (that has a width w , and a length L ) supported at 4 corners. A uniform load of wt lb/ft covers the entire top surface area of the beam. each corner has a structural tubing steel. when performing stress and loading analysis, how can I simplyfy the above to be a beam supported at two ends? is there any example or toturials that covers beams supported at 4 corners and the stress and loading analysis explained. ****this is not a homwwork problem ***
thanks

 

[PhanthomJay]

Hi
I have a wood beam (that has a width w , and a length L ) supported at 4 corners. A uniform load of wt lb/ft covers the entire top surface area of the beam. each corner has a structural tubing steel. when performing stress and loading analysis, how can I simplyfy the above to be a beam supported at two ends? is there any example or toturials that covers beams supported at 4 corners and the stress and loading analysis explained. ****this is not a homwwork problem ***
thanks

I'm not sure what you mean by 4 corners. Is the beam 'sandwiched' at each end in between 2 steel tubes at the top and bottom faces of the beam, or is this a very wide beam (flat plate, like a sheet of plywood) that sits on 2 tubes at each end, on the near and far corners of each edge?

 

[minger]

My understanding is that there are 4 cylindrical beams supporting the plate at all four corners. If so, then I really think you'll need to do some FEM on it, there will not be an accurate closed-form solution to this. Depending on the geometry, there will be stress concentration factors at the supports, and it would be difficult to model it as something simpler.

 

[FredGarvin]

It sounds like the OP is actually a plate that is supported at each corner by a column.

The simplification will all depend on what the dimensions of the original "beam" are. The word "beam" takes on a very particular definition in mechanics of materials versus a plate.

 

[nmk15]

sorry for the delay, I THOUGHT NO BODY WILL REPLY TO MY THREAD..
The wide wood beam consists of :
a wide sheet of wood 3/4 in thick with a length = 23 ft and width = 16 ft.
to bottom of this wood sheet, 27 (2 in by 12 in timber spaces 12 in apart) secured to it using wood screws.

steel beams :
I-beam: S 8X4 WITH WT PER FOOT = 23 LB
(A36 STEEL FY=36 KSI)
I-beam length = 23 ft
the I beam above is supported with one structural steel column tubing at both ends.

the square structural tubing: Fy=36 ksi and 12.02 Lb per foot
4in by 4in with 1/4in wall thickness.

the wood beam above is supported at only two sides, along the 23ft dimensions.
one i-beam and two structural tubing columns described above support the wood beam at the 23ft sides.
my goal is only to calculate : what is the maximum alloable load per square foot area.