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NW• <br /> TE NorthWest Tower Engineering <br /> Rucker Hill, Everett, WA Report No. 210621.13 April 22, 2021 <br /> Proposed P25 800 MHz TX <br /> (2) DB Spectra DS7C08PPYU-D, 4.5 ft panel (2) 7/8" Coax <br /> 285' Leg B (90 degrees) #21,22 <br /> SiteProl VFA12-HD 12' V-Frame <br /> Proposed P25 800 MHz RX <br /> (2) RFI CC807-08-T2, 9.5' Omnis <br /> 300 Leg A DQ432F83V17471T TTA (2) 7/8" Coax #23,24 <br /> SiteProl VFA12-HD 12' V-Frame 1/2" Coax #25 <br /> Proposed <br /> 125' Leg A RFS SBX6-W100DC2, 6' HP MW Dish E105 #26 <br /> (Fire Trail, 353 degrees) <br /> Proposed ' <br /> 110' Leg C RFS SBX4-W100EC, 4' HP MW Dish E105 #27 <br /> (Cultus Bay, 273 degrees) <br /> Tower geometry, structural member size, and existing antenna and feed line information was <br /> gathered during NWTE's site visits. Proposed loading was provided by Motorola Solutions, Inc. <br /> (MSI) in tower load spreadsheet 2021 rev16. <br /> Yield strengths for structural steel members are assumed to be typical of Rohn towers as <br /> follows: <br /> Pipe and Solid Round Legs 50 ksi <br /> Pipe Diagonals & Horizontals 42 ksi <br /> All Other Members 36 ksi <br /> The attached drawings show tower geometry, structural member sizes, existing antennas, feed <br /> lines, and other supported appurtenances. <br /> Wind Load Specifications <br /> Structural analyses were performed using TIA-222-G, "Structural Standard for Antenna <br /> Supporting Structures and Antennas" and TIA-222-H, "Structural Standard for Antenna <br /> Supporting Structures, Antennas and Small Wind Turbine Support Structures." The TIA-222-G <br /> standard is referenced in the 2015 International Building Code (IBC). The TIA-222-H standard is <br /> referenced in the 2018 IBC. The analysis using the TIA-222-G standard was found to produce <br /> the highest forces in the tower's structural members. Therefore only the results from the TIA- <br /> 222-G analysis are reported. <br /> The minimum basic wind speed of 115 mph (Veit, 3-second gust) for Risk Category IV structures <br /> in Snohomish County, Washington was used. A basic wind speed of 30 mph in combination with <br /> a design ice thickness of 1/4 inch as listed in the TIA-222-G standard was also considered. <br /> Exposure Category C, Topographic Category 3 (hill) with height of crest above surrounding <br /> terrain equal to 350' were used for the analysis. <br /> NorthWest Tower Engineering 3 www.nwtower.net <br /> 3426 Broadway,Suite 302,Everett,WA 98201 Tel 425-258-4248 Fax 425-258-4289 <br /> lip <br />