Strap Beam v. Grade Beam

[LUGuy]

I am reviewing an old set of plans for a cast-in-place concrete structure. The foundation plans have both strap beams and grade beams called out. The details are not discernibly different between the two.

Is there a technical difference between the two types? Does the name somehow tell a difference in their purpose and how they might have been designed?

Thanks,

 

[DaveAtkins]

My understanding is this:
A grade beam is (usually) a multiple span beam supported by footings, piles, or piers.
A strap beam is used to support a column which is too close to an existing building or property line. A properly sized footing is placed some distance back from the column which needs support. The strap beam cantilevers out to the column which needs support, and back to the first interior column.

DaveAtkins

 

[LUGuy]

In this case, the "strap beams" span from caisson cap to caisson cap. The columns are all concentrically loaded on their footings.

The "grade beams" most commonly follow under the exterior single story curtainwall, but don't necessarily tie footing to footing or column to column. They are obviously just supporting the walls in this case.

But in a couple of cases, the "grade beams" do span column to column, although they are still under the exterior wall.

Perhaps there is no deeper meaning to their labeling...

Jim