WEIGHT ESTIMATION ON SURFACES SUBMERGED IN BULK MATERIAL 1

[ALREMAN]

I now work in an industry where I am asked to design storage bins for food products and by products, etc. I often encounter a situation where I have to add a part in these bins that is going to have to support the weight of the product on top. A good example is a "turkey roost" which serves to take the weight of the product off of the belt and only allows product to enter the belt from the sides. Today I am working on a clod buster shaft that runs parallel and above a discharge auger in a large hopper full of potato by products. The question is how much weight is actually on the turkey roost or in this situation the pipe? I usually conservatively estimate the weight to be equal to the volume of product above X the bulk density of the product. However, this usually drives me to a design that is much larger than necessary. I know that a lot of the weight is carried by the walls of the bin. However, this effect diminishes the further you are away from the wall.

Does anyone have any experience here on how to estimate the weight of the column of product above a surface in a bulk material storage bin? Any help would be greatly appreciated. I have attached a picture to try to make my question more clear.

 

[robyengIT]

Roark's formulas for stress and strain - 7th edition - table 9.2 (for design of pipe)

and, may be, you can approach the calculation of load using the "soil prism theory" (ACPA American Concrete Pipe Association design manual)

furthermore : Google : "soil prism load on pipe"

 

[ALREMAN]

robyengIT thanks for the reply! This is very helpful information.