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[swati_mayekar]

Hello Structural Engineers,

I need your help to design a foundation of a NIFPS ( Nitrogen Injection Fire Protection System). This NIFPS unit is a part of protection system of a Transformer. I have seen different images of the NIFPS unit on the internet. The one thing that I observed is non-uniformity in the shape of the pedestal of this NIFPS. My questions are:

1) Are there any standards for the shape of pedestal of NIFPS?

2) Are there any standards for following aspects of foundation:

• Shape
  
• Material
  
• Minimum reinforcement
  
• Forces apart from direct load of NIFPS unit.
  
• This unit is approximately 2m - 2.5m in height. Will wind force act on this small unit?
  
• Is it must to apply earthquake fores on the foundation?
  
• Are there any Indian Standards available for this unit?

I need your help. Kindly reply.
Thank you.

With Regards,
Swati Mayekar

[vikram.jeet]

Can not reply fully,, but regarding loading, I must say that mass concrete pedestal is acted upon by :-

1 , Self  DL
2. NIFPS  unit vertical load
3 . Any associated eccentricity of Unit causing moment on mass pedestal
4. Wind load  based on wind velocity of this area
5.0 EQ horizontal force as per Seismic coefficient  of area and work out horizontal and vertical Seismic factor on structure concerned

Wind or EQ whichever has critical effects to be considered

Minimum reinforcement shall be as per IS 456 ,   IS SP 34 detailing code

But stresses in concrete must be within limits, especially tensile stresses resulted due to Eccentricity (of vertical loaf) effect plus Wind /EQ lateral forces causing moments