3301 SEAWAY BLVD MAGNIX 2023-12-06

r *2— ENGINEERING M LA 1424 Fourth Avenue, Suite 815 Seattle,WA 98101 T:206-264-2727 • F:206-264-4835 November 16, 2021 Drew Martin, P.E., S.E., City of Everett 3200 Cedar Street, 2nd Floor, Everett, WA 98201 Re: 3301 Seaway Blvd (B2108-001) - First Building Review Magnix Stand Alone Testing Room Seismic Retrofit Permit Review Responses Dear Mr. Martin: Please see below for MLA's comment responses for the seismic design for the Magnix testing frame as well as the amended calculations. Note the original permit comments are repeated and MLA's comments are provided in red. Structural Comments The structural has a 3-sided lateral system, omitting a frame on one side. The structure appears to potentially have a Type 1 a or lb Horizontal Irregularity per ASCE 7-16 Table 12.3-1. The structural calculations do not appear to include a torsional analysis. An analysis should be performed, including accidental torsion per Section 12.8.4.3 and amplification per Section 12.8.4.3 (ELFP used for analysis), and the design revised as needed. Supplemental calculations should be submitted for review. Note that the deflection check preceding the RISA model appears to be a basic deflection analysis and does not include torsional effects. Calculations have been modified and added Accidental Torsional with amplification. Note lateral loads were applied in the RISA model to in a way that reflects the distribution of the mass, and the RISA model automatically calculates stiffness, so the inherent torsion due to the rigidity vs mass in accounted for. See Appendix A for updates. Deflection has also been rechecked. See Appendix B. A story drift analysis should be performed per ASCE 7-16 Sections 12.8.4.3 and 12.12.1. The drifts should not exceed the limits of Table 12.12.1. Deflections updated to include accidental torsion. See Appendix B. The connection of the diaphragm to the vertical frames is required to comply with ASCE 7-16 Section 12.3.3.4 if a torsional irregularity occurs. Additional calculations and details may be required. See Appendix C for additional calculation for diaphragm connection and addition sketch SSK-5. The design loads are required to include a redundancy factor of 1.3 if a Type 1 b Horizontal Irregularity occurs. Model has been updated, redundancy factor is included in the EQ RISA load cases to be included in results and member forces. See Appendix A. Verify if a connection is provided between the roof panels serving as the diaphragm and the center frame line. A detail should be included. See Appendix C for additional calculation for diaphragm connection and addition sketch SSK-5. 1424 Fourth Ave,Suite 415 Tel:206.264.2727 Seattle,Washington 98101 Fax:206.264.4835