Round Wood Columns
Round Wood Columns
(OP)
Round wood columns, that is load-bearing hollow round timber columns, as sold by for example, Cox Lumber or other architectural detail vendors:
are they spaced columns?
or
are they built-up columns?
is there design guidance for these? The manufacturers give load ratings for their columns, how are they determined?
are they spaced columns?
or
are they built-up columns?
is there design guidance for these? The manufacturers give load ratings for their columns, how are they determined?






RE: Round Wood Columns
All to often, I have seen the mnfr provide ultimate loads for wood and FRP columns, only to find out that there are substantial and uncorrelated reduction factors for eccentricty, end connections, and loading configuration. All of which, cannot be calculated by standard means, as the mnfr obtained the results experimentally.
If all else fails, you can place a steel pipe column inside to carry the load. For most residential applications in the foyer or the front porch, the columns will not be loaded to the mnfr maximums. I would exercise caution using the columns at any loading near the mnfr provided ultimate.
RE: Round Wood Columns
The info I have/am using showed a "maximum allowable load" of X kips based on a particular column diameter. I noted that this load was the same regardless of column length; columns could be purchased @ 6', 8', 10', 12', 14', 16' and 18' lengths. Hmmm... So I applied the maximum loading to the maximum length and assumed the column was "built-up;" I assumed no eccentricity, assumed 10-year load, assumed wet conditions, etc., and considered the loading on one of the column pieces.
The Fc I came up with matched the manufacturer's, kind of blowing me away.
That was for my own satisfaction, but I'm contacting the manufacturer nevertheless. I sure wish the column companies would supply some good design info with their sales brochures.
RE: Round Wood Columns
RE: Round Wood Columns
Filling the column with concrete probably isn't a good idea since they lack reinforcing hoops or similar "form" appertanances.
The vendors do, however, state in their literature that the columns are "load-bearing" and, as I mentioned, show allowable loads and the columns are warranteed. If this means the vendor must certify the installation of the columns then fine; they're putting their stamp on the product. Does this mean I'm satisfied? No. I want to discuss this to my satisfaction with the manufacturer's engineer. In the case of the building I'm designing, at present hollow round wood columns have supported an active second storey for 100 years.