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BLD16-1684 - Magic Toyota - Struct Corr. Ltr #1 by Beck (4-24-2017).doc Beck & Associates, PLLC Structural Engineering & Code Consulting April 24, 2017 Leif Bjorback Building Official City of Edmonds th 121 5 Avenue North Edmonds, WA 98020-3145 Subject: Magic Toyota (Structural Review) Permit: BLD16-1684 Per your request, Beck & Associates has completed a 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. Gravity General 1)Reference page 18 of 262 of the calculations, ETABS output for gravity design. Story data is inconsistent with architectural drawings (mezzanine elevation, roof elevation). Provide coordination and revise the design (both gravity and lateral) accordingly. Lateral General 2)The story data in the ETABS analysis is inconsistent with architectural drawings (mezzanine elevation, roof elevation). Provide coordination and revise the design (both gravity and lateral) accordingly. Reference page 140 of 262 of the ETABS output for lateral design. 3)All welds used in members and connections in the Seismic Force-Resisting System (SFRS) are required to be made using filler materials meeting the requirements specified in clause 6.3 of Structural Welding Code – Seismic Supplement (AWS D1.8/D1.8M). AISC 341-10, A3.4a a)The plans need to specify this requirement. b)The plans need to identify all elements that are part of the SFRS, including chords, collectors, etc, that require compliance with these welding standards. 4)The analysis and plans need to demonstrate how the following requirements for special reinforced concrete shear walls are met. ACI 318-14 a)The required strength reduction factor for special reinforced concrete shear walls to resist shear is 0.60. 21.2.4.1 th 16425 SE 66 Street, Bellevue, WA 98006 ● beckpllc@msn.com ● PH: 206-313-3739 Permit BLD16-1684 (Structural) April 24, 2017 Page 2 of 5 b)Reinforcement in special reinforced structural walls is required to comply with special seismic requirements of 20.2.2. Longitudinal reinforcement resisting earthquake-induced moment, axial, or both is required to be A706 OR meet the reinforcement criteria of 20.2.2.5. This needs to be specified on the drawings. 18.2.6.1, 20.2.2.5 c)At least two curtains of reinforcement are required to be provided in a wall if V>2Af’ OR ucvc h/l > 2.0 (in which h and l refer to the height and length of the entire wall panel under wwww consideration). Provide an analysis to demonstrate that this requirement is met. ACI 318-14, 18.10.2.2 d)Provide an analysis to determine if boundary elements at the edges of the walls are required in any case. This is required to be determined in accordance with 18.1.6.2 or 18.10.6.3. ACI 318-14, 18.10.6 i)Where boundary elements are required, they need to meet the requirements of 18.10.6.4. ACI 318-14, 18.10.6.4 ii)Where boundary elements are not required, the requirements of 18.10.6.5 need to be met (transverse reinforcement, standard hooks at wall ends). ACI 318-14, 18.10.6.5 5)The analysis and plans need to demonstrate how the following requirements for precast members are met. Special structural walls using precast concrete are required to satisfy Section 18.5.2. Provide an analysis for the precast connections to demonstrate that these requirements will be met. ACI 318-14, 18.11 a)Connections between wall panels and connections between wall panels and the foundation are required to be designed so that yielding is restricted to steel elements or reinforcement. 18.5.2.1 b)For elements of the connection that are not designed to yield, the required strength is required to be based on 1.5 S of the yielding portion of the connection. ACI defines S as the yy yield strength of connection, based on f of the connected part, for moment, shear, or axial y force. 18.5.2.2 6)The following comments relate to design of the 2-story area located between grids 1 & 5 and grids A & H. Reference calculation pages 109-118 of 262. a)Ordinary steel moment frames are permitted to be used only to the extent allowed by ASCE 7-10, 12.2.5.6. For seismic (and architectural) considerations, this area is 2-stories in height, so the criteria of item (a) of Section 12.2.5.6 is not met. Neither are the criteria of item (b) met since the building is not light-frame construction where the floor dead load (noted as mezzanine in the calculations) does not exceed 35 psf and the dead load of walls tributary to the moment frames does not exceed 20 psf. Therefore, an alternate lateral force-resisting system will need to be utilized, perhaps steel intermediate or special moment frames. ASCE 7-10, 12.2.5.6 b)Diaphragm and collector design is required to be based on the forces determined in accordance with ASCE 7-10, 12.10.1. At the roof level, this means considering vertical distribution of seismic forces (including the mass of the mezzanine level). It does not appear that the analysis was conducted in this way. Please revise accordingly. ASCE 7-10, 12.10.1 c)The calculations do not consider the mass of the concrete panels along grid 5 for design of the roof diaphragm, chords, and collectors. A slip connection is provided for the north-south direction. However, i)The slip connection at the high roof to the Grid 5 panels needs to consider the deflection of the wall panels in addition to diaphragm deflections. ●● th 16425 SE 66 Street, Bellevue, WA 98006 beckpllc@msn.com PH: 206-313-3739 Permit BLD16-1684 (Structural) April 24, 2017 Page 3 of 5 (1)Wall panel deflection should consider that the wall is cracked (cracked section properties). (2)Mezzanine level seismic forces that are resisted by the concrete panels along grid 5 should be considered to act in either direction (north and south) to determine the worst-case deflections with respect to the high roof deflections. (3)For the worst-case condition, the deflections of the diaphragm and the wall should be considered to be in opposite directions from each other. (4)Equation 12.12-2 of ASCE 7-10 (maximum inelastic displacements) is required to be used to separate these elements. ASCE 7-10, 12.12.3 ii)There are concrete panels along grid H between grids 1 & 5 which are tributary to the 2- story area. iii)There is a concrete panel along grid A between grids 1 & 5 which is tributary to the 2- story area. d)The analysis of the moment frames do not consider the concrete panel that is located along grid 1 between grids G & H. The analysis needs to consider distribution of loads to (and compatibility with) the concrete panel along grid 1 unless the panel is somehow seismically separated from the moment frames along this line. This would require separating the panel from both the mezzanine diaphragm and the roof diaphragm. Revise the design accordingly. 7)The tilt-up panels along grid 5 should consider overstrength of the seismic forces from the mezzanine since they are essentially acting as collectors to distribute loads to the foundation and to the open parking level diaphragm. ASCE 7-10, 12.10 8)The design of the lateral-force-resisting system does not appear to consider the permanent lateral loads imposed by soils (in addition to the earthquake loads). Revise the analysis and design as required to consider these loads in the LFRS. 9)Provide calculations and design for chords and collectors at the upper level parking area. ASCE 7- 10, 12.10 10)Provide an analysis for tilt-up wall anchorage to the high roof diaphragm for the tilt-up walls located along grids A and H between grids 1 & 5 and for the tilt up wall located along grid 1 between grids G & H. The analysis is required to be in accordance with ASCE 7-10, 12.11.2. ASCE 7-10, 12.11.2 Drawing Sheets S1.5 – Typical Details and Sections 11)Reference D/S1.5. It appears that an angle or HSS may be needed to transfer loads from the girder to the diaphragm, particularly where the girder is used to resist axial loads due to out-of- plane loads. Please address. Reference S5.0 – High Roof Framing Plan. S2.0 – Foundation Plan 12)Reference the Foundation Schedule. a)According to the calculations, footing F4.5 requires (6) #5 EW BOT. Please coordinate. b)According to the calculations, footing F5.01 requires (7) #5 EW BOT. Please coordinate. c)According to the calculations, footing F5.5 requires (9) #5 EW BOT. Please coordinate. ●● th 16425 SE 66 Street, Bellevue, WA 98006 beckpllc@msn.com PH: 206-313-3739 Permit BLD16-1684 (Structural) April 24, 2017 Page 4 of 5 S2.2 – Foundation Details 13)Reference 3/S2.2. Specify the required embedment of the anchor bolts. S2.3 – Foundation Sections and Details 14)Reference D/S2.3. Provide an analysis for the design of this foundation element. Both architectural and structural plans are unclear as to what the framing conditions are and therefore what the forces are that this foundation element will be required to resist. Please coordinate. S3.0 – Mezzanine Second Floor Framing and Loading Diagram 15)Reference 3/S3.0 – Partial Floor Framing Plan at Oil Room. Provide section cuts for detailing of the connection of the roof structure to supporting concrete panels. S3.1 – Typical Composite Floor Details and Sections 16)Reference 4, 5, & 6/S3.1. #4 x 2’-0” at 18” o.c. reinforcement should be specified as “weldable reinforcement” or “A706”. 17)Reference A & B/S3.1. It appears that additional reinforcement is required at the embed plates. Please address. S4.1 – Composite Floor Sections and Details 18)Reference J/S4.1. Specify dowel size, spacing, embedment, and epoxy. S5.0 – High Roof Framing Plan 19)Identify the location and dimensions of the roof hatch as indicated on the architectural plans. The roof hatch is required to be not less than 16 square feet in area and have a minimum dimension of 2 feet. 1011.12.2 20)According to the calculations (p. 110 of 262), the WF beams along grid 1 serve as a chord. Therefore, they are required to be identified as part of the SFRS and meet the requirements of AWS D1.8/D1.8M. AISC 341-10, A3.4a S5.1 – Roof Framing Sections 21)Reference J & K/S5.1. It appears that additional reinforcement is required at the embed plates. Please address. S5.2 – Sections and Details 22)Reference 6/S5.2. Specify requirements for the connection of the W16 girder to the embed plates. S6.0 – Typical P/C Wall Panel Details 23)Reference 2/S6.0. The detail should show typical additional vertical reinforcement (2-#6 x 6’-0”, typ.). ●● th 16425 SE 66 Street, Bellevue, WA 98006 beckpllc@msn.com PH: 206-313-3739 Permit BLD16-1684 (Structural) April 24, 2017 Page 5 of 5 24)Reference 11/S6.0. It appears that additional reinforcement is required at the embed plates. Please address. S6.1 – Typical P/C Wall Panel Details 25)Reference 5 & 6/S6.1. It appears that additional reinforcement is required at the embed plates. Please address. S7.0 – Roof Wind Uplift Plan 26)For clarity, the different zones should be specified on the Roof Wind Uplift Plan. Please contact me should you have any questions. Respectfully, Douglas Beck, PE, SE Beck & Associates, PLLC ●● th 16425 SE 66 Street, Bellevue, WA 98006 beckpllc@msn.com PH: 206-313-3739