Design load criteria for old cotton mill
Design load criteria for old cotton mill
(OP)
Somewhat of a different question . . .
I am looking at a building that was constructed in 1917.
The concrete building was constructed as a three-story cotton mill.
The floor slab is 12" thick, has round columns in a 21' by 23' grid, with capitals and 3" deep by 8' square drop-heads.
The ceiling height is nearly 20', and I know the loading had to be in excess of the usual 250 psf for light manufacturing facilities, based upon the details.
Does anyone have any old references that may suggest what the design loads for the floor might have been?
I am looking at a building that was constructed in 1917.
The concrete building was constructed as a three-story cotton mill.
The floor slab is 12" thick, has round columns in a 21' by 23' grid, with capitals and 3" deep by 8' square drop-heads.
The ceiling height is nearly 20', and I know the loading had to be in excess of the usual 250 psf for light manufacturing facilities, based upon the details.
Does anyone have any old references that may suggest what the design loads for the floor might have been?






RE: Design load criteria for old cotton mill
If you have access to "Structural Renovation of Buildings" by Alexander Newman, he discusses that at the turn of the century there were quite a few proprietary concrete floor systems. I don't know what kind of information you may have available about the existing construction (drawings etc.), but this came to mind. If you had drawings that listed a type of floor system, someone out there may have some allowable load criteria for the floor system.
RE: Design load criteria for old cotton mill
RE: Design load criteria for old cotton mill
The design of the system seems to be that which was common at the time.
This system consistes of radial and circumferential reinforcement, as the design contemplated circular design slabs. In lieu of the modern design theory of column and middle strips, the design was based on a pattern of circular slabs of three different designs. One circular slab was centered over the columns, one centered between and aligned with the columns in both directions, and one in the middle. These design sections actually used reinforcing oriented radially and concentrically with the design sections, and other bars to anchor the circles to each other. It was actually ingenious, when you think about it.
However, since I do not know the size or type of the reinforcing bars, I was hoping to get a range of possible floor loadings.
If anyone else has any information, I would greatly appreciate it.
RE: Design load criteria for old cotton mill
sounds very much like the S-M-I slab system. According to Newman it was very popular in the eastern U.S.. Newman references a CRSI booklet "Evaluation of Reinforcing Steel Systems in Old Reinforced Concrete Structures", 1981.
RE: Design load criteria for old cotton mill
It is always possible to take a few investigative core samples too.