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BLD18-1498 - Mazda Service Center - STRUCT Corr. (Rvw-2, beck, 3-8-2019).doc March 8, 2019 Leif Bjorback Building Official City of Edmonds 121 5th Avenue North Edmonds, WA 98020-3145 Subject: Mazda Service Center Addition (Structural Review) Permit: BLD18-1498 Per your request, Beck & Associates has completed a second structural review of the drawings and calculations for conformance with the 2015 International Building Code (IBC), as adopted and amended by the State of Washington and the City of Edmonds. Our review of the plans and calculations indicates that corrections are necessary prior to permit issuance. The applicant should address the following comments in itemized letter format in addition to making corrections & revisions to the drawings. Corrections and revisions to the drawing should be clouded so that they are clearly identifiable. ________________________________________________________________________________ Legend: Faded text = initial comment adequately addressed – no further action required Plain text = initial comment (these remain where an additional comment is made) Blue text = additional comment in response to the resubmittal Geotechnical General The geotechnical report submitted with this permit application is dated June 23, 2017 and is titled “Showroom and Stormwater Vault Geotechnical Report”. The structural drawings reference a geotechnical report dated April 10, 2017. Please provide a report that addresses the geotechnical conditions of the Service Center. If a geotechnical report specific to the Service Center has not been provided, the geotechnical engineer should either provide one or specifically indicate that the June 23, 2017 geotechnical report contains recommendations that are applicable to the Service Center site. Gravity General Reference the Basis of Design noted on sheet S001. A floor live load of 50 psf is specified. However, a live load of 60 psf is used for the design. Provide coordination. In response to this item, the engineer references correspondence from February 4, 2019. In that correspondence, we recommended that a minimum live load of 75 psf be used for storage, but that the engineer would need to provide calculations that demonstrate that the anticipated load (based on anticipated items stored and how they are stored) does not exceed 75 psf. These calculations remain to be provided for our review. Additionally, we indicate in response to the February 4, 2019 correspondence that the design live load of the parts storage areas is required to be conspicuously posted in that part of each story where the loads apply (60 psf at storage at existing construction; 75 psf at storage at new construction). The plans need to specify this. 106.1, IEBC 402.3.1 The category in Table 1607.1 that most closely resembles the specified “Parts Storage” is “Storage Warehouses” which identifies a ‘light storage’ live load of 125 psf. IBC 1607.2 indicates that, for occupancies or uses not designated in Table 1607.1, the live load is required to be determined in accordance with a method approved by the building official. Either design the new Parts Storage for a live load of 125 psf OR provide detailed calculations for use of an alternate live load that is consistent with auto parts storage. Revise the design as required. Lateral General The new & existing structures are shown to be integrally connected (no seismic joints are provided). Reference details 5 & 6/S204. Additionally, reference comments in item 14, below. The effective seismic weight is required to include a minimum of 25% of the floor live load for all Parts Storage areas (whether existing or new). Revise the design accordingly. The effective seismic weight is required to include contribution of any masonry or concrete walls. The existence and extent of masonry and concrete walls were previously not clearly provided within the drawings (either in the architectural drawings or the structural drawings). Revise the design accordingly. Identify all existing lateral force resisting elements that are being used to resist existing and/or new lateral loads. The effective seismic weight is required to include a minimum of 25% of the floor live load for areas used as storage, such as for Parts Storage. Update the lateral analysis to consider this increase in seismic weight. ASCE 7-10, 12.7.2 Drawing Sheets S102 – Second Floor & Low Roof Framing Plan Reference Framing Note #4. A reference is made to Structural Note J.11 & J.12 on sheet S0.1. This reference is incorrect. Provide coordination. The engineer will need to revise the diaphragm design to consider that the existing and new structures share a lateral force-resisting system and to consider the required effective seismic weight. Update the design accordingly. IEBC 403.4; ASCE 7-10, 12.7.2 Provide an analysis of the new diaphragm to transfer loads to the shear wall located along grid G. Reinforce the diaphragm as determined by the analysis. Detail 8/S204 SIM TYP is specified along grid G. The cantilever concrete retaining wall is full-height at this location. Provide detailing for the specifics of this condition. S103 –Roof Framing Plan In response to this item the engineer indicates that existing elements are not being utilized to (laterally) support the Service Center Addition and that the new structure has been designed to be laterally self-supported. However, seismic joints have not been provided between the existing structure and the new structure. Reference details 5 & 6/S204. Where additions are not structural independent of the existing structure, the existing structure and its addition acting together as a single structure are required to be shown to meet the requirements of Sections 1609 (Wind) and 1613 (Earthquake). Revise the design to either truly make the existing and new structures laterally independent (with seismic joints designed per ASCE 7-10) or to consider them together as a single structure to resist lateral loads. Submit calculations to substantiate the design for the chosen approach. Update design and detailing as required. IEBC 402.4 Provide an analysis and detailing for transfer of lateral loads from the high roof (existing) into the new roof diaphragm (along grids B & F) for transfer of loads to the shear walls along grids A & G. Provide a complete load path. Additionally, where existing elements are being utilized, specify what those existing elements are assumed to be and that they must be field verified. Detail 6/S204 is called out along grid F. This detail is not applicable as it depicts TJIs, whereas the plans specify roof trusses. Provide coordination and update the detailing accordingly. S201 In response to this item, the engineer indicates that the existing building consists of portions of masonry walls, in which new door openings will be placed. Update the plans to show the locations and extent of the locations of all existing masonry walls. The plans must also indicate if the existing masonry walls are reinforced or not, and if they are, what the reinforcement in the walls is. The IEBC requires existing gravity load-carrying structural elements in which an increase in design gravity loads of more than 5% occurs to be strengthened, supplemented, replaced, or otherwise altered as needed to carry the increased gravity load required by the IBC for new structures. Additionally, any gravity load-carrying structural element whose gravity load-carrying capacity is decreased as part of the alteration shall be shown to have the capacity to resist applicable design gravity loads required by the IBC for new structures. Each existing masonry wall needs to be assessed for increased loads (where new loads are applied to them) and for decreased capacity (where being modified) to demonstrate compliance with these requirements. IEBC 402.3, 403.3 Unless the existing and new structures are laterally separated from each other with seismic joints, and if existing masonry walls are used to resist lateral loads, the engineer will need to demonstrate that the existing masonry (or concrete) walls meet the requirements for design of new structures. Alternatively, the engineer will need to demonstrate that the demand/capacity ratio of the structural element with the alteration is not more than 10% greater than the demand/capacity ratio of the structural element prior to the alteration. Please note that unless specifically seismically separated from the structure, the walls will need to be considered as part of the lateral force-resisting system. Alternatively, they must be seismically separated from the structure so that seismic loads are not imparted to them. Where no seismic separations are provided, the lateral force-resisting system will need to consider horizontal and vertical combinations of lateral force-resisting elements in accordance with ASCE 7-10, Ch. 12. IEBC 403.4 If there are unreinforced masonry walls in the existing structure, the alteration work is required to include installation of wall anchors unless an evaluation demonstrates compliance of existing wall anchorage. IEBC 403.6 Reference 4/S201. No masonry is specified on this project. Either identify the location where this detail is applicable, or if not applicable, delete it from the drawing set. In response to this item, the engineer indicates that the existing building consists of portions of concrete walls, in which new door openings will be placed. Update the plans to show the locations and extent of the locations of all existing concrete walls. The plans must identify the reinforcement of the existing concrete walls. The IEBC requires existing gravity load-carrying structural elements in which an increase in design gravity loads of more than 5% occurs to be strengthened, supplemented, replaced, or otherwise altered as needed to carry the increased gravity load required by the IBC for new structures. Additionally, any gravity load-carrying structural element whose gravity load-carrying capacity is decreased as part of the alteration shall be shown to have the capacity to resist applicable design gravity loads required by the IBC for new structures. Each existing concrete wall needs to be assessed for increased loads (where new loads are applied to them) and for decreased capacity (where being modified) to demonstrate compliance with these requirements. IEBC 402.3, 403.3 Unless the existing and new structures are laterally separated from each other with seismic joints, and if existing concrete walls are used to resist lateral loads, the engineer will need to demonstrate that the existing concrete) walls meet the requirements for design of new structures. Alternatively, the engineer will need to demonstrate that the demand/capacity ratio of the structural element with the alteration is not more than 10% greater than the demand/capacity ratio of the structural element prior to the alteration. Please note that unless specifically seismically separated from the structure, the walls will need to be considered as part of the lateral force-resisting system. Alternatively, they must be seismically separated from the structure so that seismic loads are not imparted to them. IEBC 403.4 Reference 7/S201. This detail is not specified on the plans. Either identify the location where this detail is applicable, or if not applicable, delete it from the drawing set. S202 Reference comments in item 16, above. Reference 2/S202. No masonry is specified on this project. Either identify the location where this detail is applicable, or if not applicable, delete it from the drawing set. Please contact me should you have any questions. Respectfully, Douglas Beck, PE, SE Beck & Associates, PLLC Permit BLD18-1498 (Structural – Rvw-2) March 8, 2019 Page 4 of 4 16425 SE 66th Street, Bellevue, WA 98006 ● beckpllc@msn.com ● PH: 206-313-3739 Beck & Associates, PLLC Structural Engineering & Code Consulting 16425 SE 66th Street, Bellevue, WA 98006 ● beckpllc@msn.com ● PH: 206-313-3739