Explosion Venting 1

[dik]

Not much response in the Structural area to this thread:

thread507-251026

Can anyone provide some information?

thanks, Dik

 

[burnt2x]

I got this from IEEE Gray book:

7.3 Vaults and Pads for Service Equipment - 7.3.1 Vaults
Suitable screening should be used to prevent birds, insects, vermin, or rodents from entering the shaft. The ceiling, walls, and floor should be of fire-resistant construction. Reinforced concrete is preferred. When oil insulated transformers are used and persons occupy the area adjacent to the vault wall, or when an explosion may otherwise damage a building wall, the vault walls should be sufficiently strong to withstand an explosion. The hazard may also be reduced by limiting the ratio of vault volume in cubic feet to net ventilated area in square feet. Tests indicate that where this ratio does not exceed 50:1, an 8 inch reinforced concrete wall will suffice.

Hope this helps.

 

[dik]

The present vault is located within the building and is constructed using 2 wythe and 3 wythe brick walls with some pilasters (some of these have been cut to reduce the effectiveness. I have to construct a new wall to provide 1.1m clearance to equipment.

I have to have the documents prepared by Friday and have proceeded with using 8" CMU wall for the new one. This will be reinforced using steel W columns on the outside. I will utilise 3 of the existing brick walls for bearing a 6" slab on (the vault is approx 15'x15'). I have assumed an opening for venting of approx 6'x8' and have also assumed an overpressure of 50 psf for design with the usual weasle clause that this will be revised when 'real' pressures are determined. (Everyone in the office that knows anything about this sort of thing is away until Wednesday. I will have the panels release at 25 psf. I have also vented the chanber upwards through the roof to blast outwards in two directions (2 - 6'x8' openings. Also provided for snow accumulation. I can get the documents prepared and then modify as required.

Thanks for the info...

Dik