7.6.1
All leveling plates, leveling nuts, and washers, and loose base and bearing plates that can be handled without a derrick or crane are set to line and grade by the ODRC.
7.6.2
Loose base and bearing plates that require handling with a derrick or crane shall be set by the erector to lines and grades established by the ODRC. The fabricator shall clearly scribe loose base and bearing plates with lines or other suitable marks to facilitate proper alignment.
7.6.3
Base and bearing plates that are shop attached to shipping pieces shall be set with the shipping pieces by the erector to lines and grades established by the ODRC. See Section 11.3.
7.6.4
Promptly after the setting of all bearing devices, the ODRC shall check them for line and grade, as required in Section 7.6.4(a) and 7.6.4(b). The permissible variation in elevation relative to the specified grade for all bearing devices shall be equal to or less than plus or minus 1/8 in. (3 mm). The final location of bearing devices shall be the responsibility of the ODRC.
- (a) For base and bearing plates shop attached to shipping pieces, the variation shall be measured at the top of the base or bearing plate.
- (b) For loose base and bearing plates and other leveling devices, the variation shall be measured at the top of the base or bearing plate, or devices.
Commentary
The 1/8 in. (3 mm) tolerance on elevation of bearing devices relative to established grades is provided to permit some variation in setting bearing devices, and to account for the accuracy that is attainable with standard surveying instruments. The use of leveling plates larger than 22 in. by 22 in. (550 mm by 550 mm) is discouraged and grouting is recommended with larger sizes. For the purposes of erection stability, the use of leveling nuts and washers is discouraged when base plates have less than four anchor rods.