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Mr. Carlos Alvarez <br /> 3rk Architecture Design <br /> Plan Check Number: B2107-004, First Building Review <br /> July 13, 2021 <br /> Structural - Foundation <br /> 1. The anchorage calculations have been performed considering an ordinary steel cantilever <br /> column (OSCC) system. This is not permitted in Seismic Design Category (SDC) D per AISC <br /> 341-16 Commentary Section E5.2. See also limitations on lateral systems in ASCE 7-16 Chapter <br /> 12. See IBC Section 2205.2.1.2. <br /> 2. The anchorage design has been performed considering a redundancy factor of p=1.0 per page <br /> 8 of the structural calculations. It is not clear that the lateral system complies with the <br /> exceptions of ASCE 7-16 Section 12.3.4.2 and Table 12.3-3. Note that the lateral system for <br /> the proposed building is not clear. The calculations should be revised considering p=1.3, or <br /> additional information should be submitted substantiating the lower value. See IBC Section <br /> 1613.1. <br /> 3. Structural calculation page 8 appears to specify an overstrength factor of Q=2.5, corresponding <br /> to an OSCC system. Per Foundation Comment 1 above, this system is not permitted in SDC D. <br /> The appropriate factor for the revised system should be specified. See IBC Section 1613.1 and <br /> ASCE 7-16 Table 12.2-1. <br /> 4. The load combinations on structural calculation page 8 appear to include the overstrength <br /> factor in the LRFD combinations 22 and 23. The seismic base shears appears to be 2.2 kips per <br /> page 3; one quarter of this value, or 0.55 kips, exceeds the values listed in the schedule on <br /> page 8. In addition, the calculations do not include a wind base shear for the building. <br /> However, the controlling uplift force on the anchors appears to be controlled by wind loading. <br /> The anchorage design for shear and uplift, including the seismic and wind components, should <br /> be clarified and revised as needed. The seismic design of the anchorage should include <br /> overstrength as required by ASCE 7-16 Section 12.4.3.2 and ACI 318-14 Sections 17.2.3.4.3 <br /> and 17.2.3.5.3. See IBC Sections 1613.1 and 1901.2. <br /> Structural - Building <br /> 1. The structural drawings for the steel building appear to be incomplete. Information missing <br /> includes but is not limited to the proposed lateral system and design factors and lateral framing <br /> for both principal directions. In addition, the foundation anchorage detail is incomplete; the <br /> plate thickness and welds are missing. Revised drawings should be submitted for review. See <br /> IBC Sections 107.2.1, 1603.1, 1604.4, and 1613.1, and ASCE 7-16 Section 12.2.1. <br /> 2. The building drawings do not specify a lateral system. Per Foundation Comment 1 above, the <br /> building appears to be designed using an OSCC system, which is not permitted in SDC D. An <br /> approved lateral system should be specified. <br /> 3. Structural calculations have not been included in the application documents and should be <br /> submitted for review. Preliminary comments have been provided below; additional comments <br /> may be issued pending review of the calculations. See IBC Sections 1604.1 and 1604.4. <br /> 3200 Cedar Street © 425.257.8810 O everetteps@everettwa.gov <br /> Everett,WA 98201 425.257.8857 fax everettwa.gov/permits <br /> Page 2 of 3 <br />