2017-0041 Madrona Struc Beck #2.pdf
Beck & Associates, PLLC
Structural Engineering & Code Consulting
June 30, 2017
Leif Bjorback
Building Official
City of Edmonds
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121 5 Avenue North
Edmonds, WA 98020-3145
Subject:Madrona K-8 (Structural Review)
Permit:2017-0041
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Per your request, Beck & Associates has completed a 2 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.
_______________________________________________________________________
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
1)The geotechnical engineer, Shannon & Wilson, Inc., is required to review the submitted
permit plans and specifications that pertain to the geotechnical aspects of the project to
determine if they are consistent with the recommendations (p. 18). Shannon & Wilson, Inc
shall prepare a letter summarizing their review and identifying any recommendations for
revisions to the plans. All recommendations are required to be addressed in the resubmitted
plans.
General
2) Reference sheet S-111C. Both footing E and a 4x8x30’ footing are called out for the same
canopy footings. Please coordinate.
Reference detail 27/S-609. Specify the required width of the plinth. Additionally, it may be
helpful to locate the plinths on the foundation plan.
Provide complete analysis and design for the following elements:
a)Walkway covers occurring between buildings
b)Covered Play area
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16425 SE 66 Street, Bellevue, WA 98006 beckpllc@msn.com PH: 206-313-3739
Permit 2017-0041 (structural)
June 30, 2017
Page 2 of 4
S-101 through S103 –General Structural Notes
3)Reference the Design Loading Criteria on S-101.
a)The correct response modification factor for the Small Canopies, consistent with the
calculations, is R=2.5 Steel Special Cantilever Column System, not R=1.25. Update the
plans accordingly.
Specify lateral force resisting systems used for canopies, play structure, etc.
b)Identify the base shear for each individual structure.
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4)Reference note 33 on sheet S-102 (2 paragraph). Specify wind uplift pressures for which
joists are required to be designed.
5)Reference not 34 on sheet S-102. Welds that are part of the seismic force resisting system
(SFRS) are required to comply with clause 6.3 of AWS D1.8/D1.8M. This needs to be specified
in the General Structural Notes. Additionally, the steel elements that are part of the SFRS are
required to be identified on the plans.
S-111A – Foundation Plan Zone A
6)Provide an analysis for the covered walkway located along grid 3 between grids D.5 and F.8.
7)Reference the Mechanical Level Framing Plan. Section 6/S-602 is called out. However, this is
an incorrect reference. Should the reference be to 12/S-602?
8)In response to this comment the structural engineer provided calculations for bracing the top
of the sliding glass partition (2x4@48” o.c.) for a base load of 5 psf. However, calculations
were not provided to check seismic loads to see if they govern. Additionally, the engineer
referenced B3/A552 for bracing requirements. B3/A552 does not specify bracing.
a)Provide calculations to determine if out-of-plane seismic loads govern lateral bracing of
the top of the sliding glass partition.
b)Provide detailing for connection of required bracing to the head of the sliding glass
partition framing and to the main building structure.
c)Provide coordination with the architect for detailing of the brace and the connection at
each end of the brace.
Reference the architectural plans (A-121A) which identify a folding partition located between
101T and 101P (Prof Dev/Staff Lounge). Provide an analysis for and design of gravity support
and bracing as required to brace the top of the folding partition against out-of-plane loads.
S-111B – Foundation Plan Zone B
9)Reference the W6 shear wall located along grid C.3 (adjacent to the restrooms). The shear
wall differs substantially from the conditions assumed in the calculations. Please coordinate.
10)Reference the W4 shear walls located along grid A.3. Calculations show that the shear walls
(B6-NS/8) should be 2W3 shear walls in lieu of W4 shear walls. Please coordinate.
11)Reference the W2 shear wall along grid A.2 (between grids 3.4 & 4). The shear wall differs
substantially from the conditions assumed in the calculations. Please coordinate.
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16425 SE 66 Street, Bellevue, WA 98006 beckpllc@msn.com PH: 206-313-3739
Permit 2017-0041 (structural)
June 30, 2017
Page 3 of 4
S-121A – Roof Framing Plan Zone A
12)Reference the Seismic Force Resisting System Legend. The Strut Truss note should specify the
spacing of the 10d nails.
13)Reference the Plan Notes.
a)Note 1 specifies T&G plywood with a span rating of 32/16. However, note 3 specifies
wood trusses to be spaced at 48” o.c. The spacing for wood trusses is 24”o.c. per the
calculations. Please coordinate.
b)Specify the spacing of steel trusses. It appears that the spacing is 48” o.c.
14)Are the steel trusses required to be designed to resist any axial forces due to out of plane wall
loads on the west side of the Gym?
15)The analysis of the brace appears to apply an incorrect load to the brace. The horizontal load
was determined to be 50.4k. This would result in a horizontal force of 50.4k/cos(36) = 62.3k.
The load used for design appears to be based on 50.4k x cos(36), which would be incorrect.
The horizontal load that needs to be transferred is 50.4k, realizing a higher force in the brace.
Please review and revise the design/analysis and detailing (S-604) accordingly. Reference the
attachment at the end of this review letter.
Provide a complete analysis and design for the diagonal tension bracing as specified along
grid G per detail 24/S-604. Bracing will essentially serve as a collector to transfer loads and
should be designed considering overstrength. Alternatively, it would need to be designed as a
part of the seismic force resisting system, SFRS, with an appropriate response modification
factor, R, with consideration given to different systems being used in a SFRS. ASCE 7-10
16)Detail 24/S-604 appears to be cut at an incorrect location.
17)Provide an analysis for the covered walkway located along grid 3+ between grids D.5 and F.8.
S-121B – Roof Framing Plan Zone B
18)A notes states: “See Sheet S-205 for Plan Notes and Legends.” It appears that the reference
should be to S-121A. Please coordinate.
19)Specify the required seismic joint along grid 5, located at grid D.
S-121C – Roof Framing Plan Zone C
20)A notes states: “See Sheet S-205 for Plan Notes and Legends.” It appears that the reference
should be to S-121A. Please coordinate.
21)Specify the required seismic joints between the covered walkway and the buildings.
22)Provide an analysis and collectors/strapping in order to transfer lateral loads from the roof
into the shear walls running in the longitudinal direction.
23)It appears that 26/S-604 and 30/S-604 should be called out for connections from strut trusses
to shear walls along grid C, similar to grid B. Please address.
Provide section cuts and detailing at interior and exterior shear walls in the longitudinal
direction. Provide a complete load path.
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16425 SE 66 Street, Bellevue, WA 98006 beckpllc@msn.com PH: 206-313-3739
Permit 2017-0041 (structural)
June 30, 2017
Page 4 of 4
S-121D – Roof Framing Plan Zone D
24)A notes states: “See Sheet S-205 for Plan Notes and Legends.” It appears that the reference
should be to S-121A. Please coordinate.
25)Specify the required seismic joints between the covered walkways and the buildings.
26)Provide an analysis and collectors/strapping in order to transfer lateral loads from the roof
into the shear walls running in the longitudinal direction.
27)It appears that 26/S-604 and 30/S-604 should be called out for connections from strut trusses
to shear walls along grid J, similar to grid H. Please address.
Provide section cuts and detailing at interior and exterior shear walls in the longitudinal
direction. Provide a complete load path.
S-502 – Steel & Metal Deck Details
28)Detail 6/S-502 needs to be completed. There is missing information.
S-503 – Misc. Steel Details
29)Provide an analysis for the design of the covered walkways.
S-607 – Covered Play Framing Plans and Details
30)Provide an analysis and complete detailing for the design of the Covered Play Framing.
Please contact me should you have any questions.
Respectfully,
Douglas Beck, PE, SE
Beck & Associates, PLLC
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16425 SE 66 Street, Bellevue, WA 98006 beckpllc@msn.com PH: 206-313-3739