Loads to the Walls of Hopper Generated by Bulk Material 5

[Algirdas13]

Hey everyone,

At the moment I'm designing steel hopper and a slide gate valve. During designing phase I struggle to estimate the loads to the walls of hopper and slide gate valve. The hopper will be loaded by pile of household waste. I tried to use the hydrostatic load but it seems to be too conservative approach. The density of waste is approximately 300 kg/m3.

Maybe someone could share some insights or ideas how to estimate loads to the side walls of hopper and load to the slide gate valve?

Thanks in advance!

 

[bugbus]

Treat it like a granular soil I guess?

 

[sdz]

In Australia; AS 3774 Loads on bulk solids containers.
I'm sure there will be an equivalent in your country.

 

[human909]

"Household waste" is a vague term. You are going to have to be more specific. At a bulk density of 300kg/m3 it doesn't sound like sewage it sound more like miscellaneous 'rubbish' or recycling material. In which case you will only get inferred guidance from bulk material codes like AS3774, ANSI/ASAE EP433 or EN 1991-4.

If it is rubbish or recycling material, be conservative. I've done work in MERFs and they are tough on equipment! I'd be focused on point loads and ensuring a design suitable for plenty of wear and tear.

In Australia; AS 3774 Loads on bulk solids containers.

FYI. This standard has now been withdrawn and not replaced. (It took me almost 2 years to realise that!)

IMO it is better to use EN1991-4 instead even if you normally use AS codes. The code is almost completely superior. It is an evolution of AS3774, both codes spearheaded by John Michael Rotter a leading academic in the field. He left Australia for the UK and never come back. As such AS3774 has been untouched for years.

 

[HTURKAK]

IMO ,the easy part of the problem is , to predict the loads to the walls of hopper and slide gate valve. I am not sure that the proposed set up will be OK for household wastes with density approximately 300 kg/m3. My concern would be , the waste is compressible material and will squeeze itself then plug will form.

I will suggest you to look ,

- EN 1993-4-1_ 2007 Eurocode 3 - Design of steel structures - Part 4-1_ Silos,
- BS EN 1991-4 Eurocode 1 — Actions on structures — Part 4: Silos and tanks
- BOWLES , Foundation analysis and design,
- Dynamisches Verhalten von Schüttgütern beim Entleeren aus Silos





Use it up, wear it out;
Make it do, or do without.

NEW ENGLAND MAXIM

 

[dik]

HTURKAK... good reference. Thanks.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[Algirdas13]

Hi guys,

Thank you very much for all the insights regarding the discussed topic. All the insights were very helpful to get on the right track!

 

[SWComposites]

and don't overlook the fact that the material will be dumped from trucks into the hopper, so loads are not just weight of material but impact loads. worst case might be a dump truck load of concrete rubble. go out to your local recycling or waste transfer station and look at the equipment; very likely they are beat to hell. so don't under design them!