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<br /> 76th Street, Everett, WA Report No. 210622.08 February 1, 2021
<br /> 14. Proposed VHF Simplex SNOFIREIO TX/RX
<br /> 158' Leg C RFI COL53-160, 16.5' Omni 7/8" Coax #26 g
<br /> 6' Standoff Mount
<br /> Proposed P25 800 MHz TX
<br /> I. 165' Leg A (2) RFI BPA7496-180-11, 5' Panels (100 deg) (2) 7/8" Coax #27,28
<br /> SiteProl VFA12-HD, 12' V-Frame
<br /> Existing Proposed P25 800 MHz RX (2) 7/8°' Coax #29,30
<br /> • 178' 4' Standoffs (2) RFI CC807-08-T2, 9.5' Omnis /2°° Coax #31
<br /> e Legs B & C DQ432F83V17471T TTA
<br /> Proposed
<br /> § 98' Leg B RFS SCX3-W100BC, 3' HP MW Dish E65 #32
<br /> (OEM) t
<br /> Remove
<br /> 6' HP MW Dish RemoveEW90 #16
<br /> t 151' Leg B Proposed
<br /> RFS SBX6-W100DC2, 6' HP MW Dish Proposed #33
<br /> fz (Clearview) E105 z
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<br /> Antenna center elevations are listed for microwave, yagi, and panel type antennas. Base
<br /> elevations are listed for other antenna types.
<br /> Existing antenna and feed line information was gathered during NWTE's site visit. Proposed
<br /> loading was provided by Motorola Solutions, Inc. (MSI) in tower load spreadsheet 2021 rev16.
<br /> Yield strengths for structural steel members are assumed to be typical of Valmont towers as
<br /> follows:
<br /> i- Pipe Legs 46 ksi
<br /> y Angle Diagonals & Horizontals 36 ksi
<br /> y- All Other Members 36 ksi
<br /> The attached drawings show tower geometry, structural member sizes, existing and proposed
<br /> antennas, feed 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 (\Li,t, 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 /> NorthWest Tower Engineering 3 www.nwtower.net
<br /> 3426 Broadway,Suite 302,Everett,WA 98201 Tel 425-258-4248 Fax 425-258-4289
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