12.20 PERMANENT SIGNING
12.21 ACCEPTANCE OF SIGNS ON SIGNING CONTRACTS
For contracts requiring a number of widely scattered signs to be erected along a highway open to traffic, damage resulting from vandalism is beyond contractor control. After the contractor has completed a given section of the project, i.e. Interstate 80 east of Des Moines, the project engineer should accept partial completion of the work in accordance with Specification 1107.13. This will partially relieve the contractor from vandalism loss.
12.22 OVERHEAD SIGN TRUSS CONSTRUCTION
The precise aligning and erecting of all components of the overhead sign truss and its supports shall be considered essential to the performance of the installation. The project plans for future overhead sign truss construction will include plan notes regarding critical construction tolerances and will require the contractor to submit documentation to the Engineer showing that the various components have been measured and are located within the tolerances specified in the plans.
To assist the inspector in monitoring the construction of overhead sign trusses, an Overhead Sign Truss Construction Checklist is provided in Appendix 12-8. This construction checklist addresses important checks related to Foundations & Anchor Rods, Aluminum & Steel Components, and final checks of the completed aluminum and steel structure.