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R <br /> ENGINEERS <br /> STRUCTURAL PLAN REVIEW RESPONSE <br /> Project: Everett WA Sunbelt Wash Bay <br /> Date: August 24, 2021 ARW Project No: 21114 <br /> Engineer of Record: David L. Pierson, SE License #: 39160 <br /> Reviewed By: Drew Martin, PE, SE ompany: Everett City <br /> D <br /> RE: Plan Review Response MAR 0 4 2022 <br /> Items Reviewed: 0{ Se VRC S <br /> Perm <br /> Structural — Foundation CITY <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 /> ARW Response: The steel structure was designed as an Ordinary Moment Frame (OMF) and <br /> Ordinary Concentric Braced Frame (OCBF) system. The calculations and drawings have been <br /> revised to reflect this. <br /> 2. The anchorage design has been performed considering a redundancy factor of 0=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 f, =1.3, or <br /> additional information should be submitted substantiating the lower value. See IBC Section <br /> 1613.1. <br /> ARW Response: Calculations revised to use p = 1.3. <br /> 3. Structural calculation page 8 appears to specify an overstrength factor of 0)=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 /> ARW Response: Calculations revised to use ( = 3.0 for an Ordinary Moment Frame system. <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 /> ARW Response: Comply. Seismic and wind base shears provided by the PEMB supplier on <br /> ARW Engineers• 1594 Park Circle• Ogden, Utah 84404• Phone (801)782-6008• Fax (801)782-4656 <br /> // <br />