Neb. Rev. Stat. § 39-814: Neb. Rev. Stat. § 39-814

In the event the substructure of such bridges or approaches is wholly or in part of iron, steel or other metal, the contract for the portion of the substructure to be built of iron, steel or other metal shall be let at a specified sum per lineal foot for tubing, and at a specified sum per pound for all other metal in place.