Designing An Isolated Foundation
If the genset cannot be mounted directly on a floor slab, or if it is desirable to isolate it from the floor slab, then a separate foundation slab must be designed.
A massive concrete foundation is not required. Outside dimensions of the foundation should exceed the outside genset dimensions by 12in (300mm).
For single genset installation, the foundation weight should be a minimum of 1.50 times the genset wet weight.
For multiple genset installation, the foundation weight should be a minimum of 2.0 times the genset wet weight.
Figure 2‐3 shows a method to calculate foundation thickness and the soil bearing load of the foundation and generator set. The soil load bearing capacity under the foundation must equal or exceed the load from the foundation and genset. If it does not, then a footing, as shown in Figure 2‐4 must be added to spread the load over a larger area.
Figure 2‐3 Calculate Soil Bearing Load (SBL) Capacity
Figure 2‐4 Typical Footing on Foundation in Soil With Low Soil Load Bearing Capacity
MN2408 | General Information 2‐7 |