Is there a standard or formula for calculating the size and depth of a concrete base for Parking Lot Lighting? In other words a certain size pole in a certain geographical area need a base so many inches in diameter at a depth of so many feet with so many feet exposed.
I suspect that is a local building code issue. The standard pole spec is to withstand 70 mph wind load. There are standard formulas to figure out what that would be in terms of a moment at the base but, if there is no code, an engineer would have to sign off on the actual base. We had some trouble here. Our building was designed by the Corps of Engineers. We needed to modify some exterior lighting due to a new runway being constructed the other side of our common fence with the airport. The specs called for 100 mph poles and the contractor had lots of problems finding anything that met those specs. Oh,well, the city wanted the runway so they paid for all our changes.
Re: Pole base for Parking Lot Lighting#40480 07/22/0408:52 AM07/22/0408:52 AM
Let the engineers do the math. It depends on the height of the pole, the weight of the pole, the wind speed anticipated, the wind resistance of the pole, the soil characteristics, and the water table and the likelyhood of flooding.
Re: Pole base for Parking Lot Lighting#40481 07/22/0409:03 AM07/22/0409:03 AM
We set 18 40' steel poles today. Each pole had a triple yoke on top for 3 1000w MH floods. I wouldn't even venture a guess about the wind load on that arrangement. The bases were built as specified. I wouldn't want to guess on something like this.
BTW the installation went very smooth. The crane operator was good and followed directions well, which always helps.