Grouting shall be the responsibility of the ODRC. Leveling plates and loose base and bearing plates shall be promptly grouted after they are set and checked for line and grade. Columns with attached base plates, beams with attached bearing plates, and other similar members with attached bearing devices that are temporarily supported on leveling nuts and washers, shims, or other similar leveling devices, shall be promptly grouted after the structural steel frame, or portion thereof, has been plumbed.
Commentary
In the majority of structures, the vertical load from the column bases is transmitted to the foundations through structural grout. In general, there are three methods by which support is provided for column bases during erection:
- (a) Pre-grouted leveling plates or loose base plates
- (b) Shims
- (c) Leveling nuts and washers on the anchor rods beneath the column base
Standard practice provides that loose base plates and leveling plates are to be grouted as they are set. Bearing devices that are set on shims or leveling nuts are grouted after plumbing, which means that the weight of the erected structural steel frame is supported on the shims or washers, nuts, and anchor rods. The erector must take care to ensure that the load that is transmitted in this temporary condition does not exceed the strength of the shims or washers, nuts, and anchor rods. These considerations are presented in greater detail in AISC Design Guide 1, Base Plate and Anchor Rod Design, and AISC Design Guide 10, Erection Bracing of Low-Rise Structural Steel Frames.