Loading...
HomeMy WebLinkAboutMISC_Fall Radius Letter_20221201_v1Truc Lac, PE. SE. Senior Project Engineer Tower Assets Tel 713-570-3849 Truc.lac@crowncastle.com Crown Castle 2000 Corporate Drive Canonsburg, PA 15317 Date: August 18, 2022 Subject: Code Compliance Letter Crown Castle Designation: BU Number: 831070 Site Name:A-Team Site Data: 2902 NE 12th St, Renton, WA Latitude 47° 30ƍ 13.92Ǝ, Longitude -122° 10ƍ 49.94Ǝ 94 Foot – Monopole Tower This letter is to attest to the structural integrity of the Crown Castle owned tower at the above-mentioned address. Crown Castle structures are designed in conformance with the Telecommunication Industry Association Standard (TIA), which is referenced in the building code adopted by the governing local jurisdiction. This tower structure has been designed on August 08,2022, in accordance with the requirements of the 2018 International Building Code and the referenced TIA Standard, TIA-222-H, considering a 98 mph ultimate 3-second gust wind speed. The tower and foundation were designed to be in conformance with current building code requirements. The design wind loads per ASCE 7-16, Minimum Design Loads for Buildings and Other Structures (referenced in the 2018 IBC), have a mean recurrence interval of 700 years (i.e. the probability of a design level wind event in any given year is 1/700, or 0.143%). The design seismic (i.e. earthquake) loads based on ASCE 7-16 are intended to result in structures that have a 1% probability of collapse in 50 years, which is equivalent to a mean recurrence interval of 4975 years, or 0.0201%. Note that wind effects control over seismic effects for this tower. Extreme weather conditions (e.g. tornadoes), excessive corrosion, vehicle impact, or damage due to vandalism are outside of this scope of design and are examples of conditions that might result in tower damage, and in rare instances, tower collapse. Corrosion resistant coatings, regular inspection and maintenance, and fencing around the tower compound are intended to minimize these risks. However, based on the information in the preceding paragraph and to the best of our knowledge, we can state that the tower has been designed in accordance with the manufacturer’s specifications, meets the requirements of the building code, and therefore presents no safety issues to adjacent properties at this time. Therefore, it is the position of Crown Castle Engineering that the tower has a theoretical fall zone under the design requirements of the building code of zero feet. Please contact the undersigned with any questions. Truc Lac, P.E., S.E. Senior Project Engineer 08/18/22 License Expires: 02/24/20