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Structural Review Response to Comments 1.pdfENGINEERS November 03, 2017 Steve Barnes Cornerstone Architectural Group Sub: Response to Structural Review by Douglas Beck: 8509 2441h ST SW, Edmonds, WA 98026 Steve: We are writing in response to the structural review comments dated 08/29/2017. Our response is in Times New Roman font style under each comment: PSM Response to Reviewed Comments in Structural Package Comment#]: All exterior deck framing members should be clearly identified as preservative -treated. A note is included in the General Notes. However, it is prudent to clearly identify them as preservative - treated on the plans to ensure proper construction. RESPONSE: We have updated our framing plans of both buildings and have added key plans to clearly present extent of exterior deck where preservative treated lumber is required Comment#2: Provide an analysis for design of basement retaining walls (E/S4.1). RESPONSE: Please see calculation package (page#2) of this submittal for the same. Comment#3: Provide calculations for determination of the overall seismic weight used in determining seismic forces. The seismic weight is required to include dead loads of all elements including the weight of non-structural partitions, exterior walls & cladding, etc. Revise the design as required. ASCE 7-10, 12.7.2. RESPONSE: See attached seismic weight calculation package (page#18) of this submittal for the same. Comment#4: Reference the Structural Loads section. a) Decks are required to be designed for a live load of 60 psf. 1607 i) This needs to be identified in the Structural Loads section of the General Notes. ii) Update the calculations of decks and update the drawings as determined by the analysis. RESPONSE: Drawings have been updated accordingly. Please see attached calculations (page#25) of the is submittal for the same. Comment#S: The Foundations section should be updated to include all geotechnical recommendations utilized for structural design, such as active lateral wall earth pressures, passive earth pressures, coefficient of friction, seismic surcharges, etc. RESPONSE: Please see detail 3/S4.1 of the revised drawing set for the same. Comment#6: Section cuts C, F, & G/S6.0 should be called out at all locations where they occur on the plans in order to ensure proper construction and inspection. 2200 6TH AVENUE, #601 WWW.PSM- ENGINEERS.COM PHONE 206-622-4580 SEATTLE WASHINGTON 98121 USA FAX 206-622-0422 P:A CONSULTING ENGINEERS RESPONSE: The framing plans have been updated with reference callouts as requested. Comment#7: It appears that detail EIS4.1 should be called out on the plans at the following locations. Update the plans accordingly. a) Grid A between grids I & 1.5 b) Grid E between grids I & 3 c) Grid D between grids 3 & 5 RESPONSE: The foundation plan has been updated with reference callouts as requested. Comment#8: Specify continuous footing sizes for the footings located on each side of the stairs. RESPONSE: These are not footings but rather landing pads at stair landing. We are proposing SOG with thickened edge. Final extents to be coordinated with ARCHT and GC during construction. Comment#9: It appears that a foundation wall is required under the bearing wall located along grid 3.3. Please coordinate. RESPONSE: Foundation plan has been updated to this extent. Comment#10: The footing along grid 4.5 should be extended upward (west) to pickup bearing loads from above. RESPONSE: Foundation plan has been updated to this extent. Comment#11: The following beams support discontinuous shear walls and holdowns from above. These beams, and their end connections to framing below, are required to be designed for seismic loads considering overstrength. Provide an analysis for the design of these beams and update the drawings as determined by the analysis. ASCE 7-10, 12.3.3.3 a) Beam G3 b) Beam G8 (2 locations) c) Beam G18 RESPONSE: See attached calculations package (page#40) of this submittal for the same. Comment#12: Where shear walls are discontinuous, the design seismic forces are required to be amplified by 25% for design of the following elements. Provide an analysis and update the drawings as determined by the analysis. ASCE 7-10, 12.3.3.4 a) Connections of diaphragms to vertical elements and to collectors b) Collectors and their connections, including connections to vertical elements, of the seismic force -resisting system RESPONSE: Please see attached calculation package (page#48) of this submittal for the same. We have provided the lateral analysis and design of building#2 for all levels and have updated our drawing set with required straps along with revising extent of blocked diaphragm to ensure that all codal provisions are met. 2200 6TH AVENUE, #601 WWW.PSM- ENGINEERS.COM PHONE 206-622-4580 SEATTLE WASHINGTON 98121 USA FAX 206-622-0422 P:A CONSULTING ENGINEERS Comment#13: Provide an analysis and design for shear transfer to the shear walls located along grids 2.5 and 3.5 (Shearwall-C and Shearwall-D of the calculations). It appears that collectors and/or increased diaphragm nailing may be required. RESPONSE: Please see response to comment#13.. Comment#14: Section cuts C, F, & G/S6.0 should be called out at all locations where they occur on the plans in order to ensure proper construction and inspection. RESPONSE: The framing plans have been updated with reference callouts as requested. Comment#15: It appears that a holdown is required at the lower end of the shear wall located along grid 3.5 between grids A & B (Shearwall-DI of the calculations). Please review this condition. RESPONSE: We have re -reviewed the holdown layout at referenced location and updated the plans as requested. Comment#16: Reference details H & JIS5.0. Speck required connection of the blocking to the shear wall top plate below. RESPONSE: The referenced detail has been updated. omment#17: Reference detail FIS5.1. Speck required connection of the blocking to the shear wall top plate below. RESPONSE: The referenced detail has been updated. Comment#18: Reference detail FIS6.0. Identify all elements in order to provide shear transfer from the roof diaphragm to the shear wall below. RESPONSE: The referenced detail has been updated. Please feel free to call us with any questions or comments regarding the contents of this document. Thank you. Sincerely, Marc David Stubbs, P.E., S.E. PSM Engineers 2200 6TH AVENUE, #601 WWW.PSM- ENGINEERS.COM PHONE 206-622-4580 SEATTLE WASHINGTON 98121 USA FAX 206-622-0422