This work includes furnishing and installing mast arm poles, combination mast arm / lighting poles, and all miscellaneous items. Mast arm poles, combination mast arm / lighting poles, shall be galvanized steel or aluminum structures designed in accordance with the 2013 AASHTO Specifications for the Design and Construction of Structural Supports for Highway Signs, Luminaires and Traffic Signals, 6th Edition. A Structural Engineer currently licensed to practice in the State of Nebraska shall seal all designs. The design wind velocity shall be ninety (90) miles per hour. The following design factors shall be used in the design of mast arm pole and combination mast arm / lighting poles: • Wind Speed: 90 mph wind speed. (AASHTO Section 3.8.2, Figure 3.8.3) • Wind Recurrence Intervals: 50-year recurrence interval. (AASHTO Section 3.8.3) • Unreinforced & Reinforced Holes and Cutouts: Design structure unreinforced and reinforced holes to conform to section 5.14.6 (AASHTO Section 5.14.6) • Fatigue Category: Fatigue Category 2 (AASHTO Section 11.6)
