Partition Wall Pressure Loads in Mines
Partition Wall Pressure Loads in Mines
(OP)
I am designing a fire-rated partition wall in a mine roughly 1200 feet below grade. In a normal building application, I would design for the code required 5 psf minimum (IBC 1607.13). Does anyone know if the pressure would be greater for any reason because I am 1200 feet below grade?






RE: Partition Wall Pressure Loads in Mines
In a 1200 foot deep mine fire would usually come with a possible explosion and movement, so the 5 psi is minimal.
The normal fire ratings (2 hour, 3 hour, 4 hour) are for walls to prevent the escape of gasses and temperature and they are usually tested with a vertical load with a fire hose blast since the combined loadings on masonry walls can be resisted and it is cheaper to test a single wall for both loadings.
The big question is the lateral load and 5 psi is not that much, especially if there is possibility of earth movement also. Don't forget about the anchorage to Terra firma (pun intended).
Dick
Engineer and international traveler interested in construction techniques, problems and proper design.
RE: Partition Wall Pressure Loads in Mines
RE: Partition Wall Pressure Loads in Mines
When I have a heavily loaded partition, like with xray shielding or veneer, I always compare my seismic load Fp using the actual wall weight. For most typical interior partitions, 5 psf is greater than or approximate to Fp x self weight of the wall.
RE: Partition Wall Pressure Loads in Mines
RE: Partition Wall Pressure Loads in Mines
http://en.wikipedia.org/wiki/Arc_flash
RE: Partition Wall Pressure Loads in Mines
Some mine materials, potash for example, 'creep' and the lateral pressures can be high... I've used foam voidform or an actual 'airspace' to minimise lateral pressures.
Dik
RE: Partition Wall Pressure Loads in Mines
RE: Partition Wall Pressure Loads in Mines
What EXACTLY is the wall designed to guard against. Blast within the MCC room or blasts outside the room causing damage to the electrical equipment.??
RE: Partition Wall Pressure Loads in Mines
RE: Partition Wall Pressure Loads in Mines
What type of wall is it? Concrete.. metal stud with gypsum for your fire rating? Is it shaftwall construction because of accessibility on 1-side? If it is a metal stud wall, I would use a 6" x 16 gauge (similar to an exterior wall on a building) and use that if there is high pressure concerns. But, this isn't my area of expertise, so I should probably shut up.
RE: Partition Wall Pressure Loads in Mines
RE: Partition Wall Pressure Loads in Mines
RE: Partition Wall Pressure Loads in Mines
Sounds like a good plan. That will give you a 3 HR rating. Very similar to a high security prison I was involved in - Concrete columns, post tensioned slabs (2 to 4 floors) and ground 8" CMU walls (250,000 units) vertically reinforced at 8" for security using special shapes. Anchoring the vertical rebars was a challenge when drilling into the slabs ans special block were used to allow dry packing of the top course of horizontal steel. Lots of angles, but the CMUs could easily be moved around and installed between the walls with many jogs, angles and openings.
In a mine, the logistics for block, rebar grout and mortar should not be a problem. Forming and placing concrete for walls is a much bigger problem.
Dick
Engineer and international traveler interested in construction techniques, problems and proper design.
RE: Partition Wall Pressure Loads in Mines