1) Natural frequency of the system should not be within 20% of the operating frequency of machine
2) The bearing pressure on the soil should be within 50% of the allowable value used for building foundation
3) The weight of the foundation need to atleast 3.0 times the weight of machine to minimize vibration
4) The minimum reinforcement In each direction: 0.18%
5) Horsepower >=500, The foundation shall be designed for the expected dynamic forces as per the code
6) Horsepower <500 & total weight < 30 kN, The foundation shall be designed for static checks only
7) Minimum thickness of concrete foundation = Greater of((width/5, Length/10, 2ft) & (L/30+0.60m))
8) Minimum width of footing = 1.0 to 1.5 times the vertical distance from base of footing to machine centerline
9) Minimum size of rebar shall be 13mm
10) Maximum allaowable eccentricity in both direction in plan shall be 5% of width or length respectively
11) High tuned foundation = Operating frequency of machine is below natural frequency of system (SBC = 50% of Allowable)
12) Low tuned foundation = Operating frequency of machine is above natural frequency of system (SBC = 75% of Allowable)
13) If Rotor Wt of machine > 1/100( Weight of machine + foundation ) detail dynamic analysis should be performed
14) If Dynamic force of machine > 1/1000( Weight of machine + foundation ) detail dynamic analysis should be performed
30 Nov 2014
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