Reviewed by: Bolen, Wayne A. Permit #: C11-2221
Phone: 343-8072 Date: 11/15/2012
Fax: 249-7393
Email: BolenWA@muni.org
Permit Manager: Jinny Day
Phone: 343-8338
Email: DayJR@muni.org
Project: TNA Hanger and Office Building
Review Number: 306321
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PERMIT STATUS (no response required) 7/16/2012: Review completed. Comments issued.
9/18/2012 – Responses reviewed. Comments issued.
10/18/2012 – Responses reviewed. Comments issued.
11/15/2012 – Responses reviewed. Comment issued.
Advisory Comment (no response required): This review is based on the requirements of the Anchorage Administrative Code (AAC), 2009 International Building Code (IBC), 2009 International Residential Code (IRC) and all adopted references thereto as amended by MOA. The following comments must be addressed before a permit can be issued. The approval of plans and specifications does not permit the violation of the codes, or any federal, state or local regulations.
1. LOAD PATH FROM ROOF TO SHEAR WALLS
Reference the drawings. Please provide details showing the lateral load path from the roof diaphragm to the shear walls. A detail needs to be provided at both shear walls where the trusses frame perpendicular to the wall, and another where the truss frame parallel to the shear walls. Reference ASCE 7-05 section 12.1.3 and AAC section 23.10.104.8.
Comment remains. The load path from the roof diaphragm to the walls is still not clear. There is a section parallel to the trusses shown on sheet S-3, but the load path on either side of the structure isn’t clear as it doesn’t appear that the diaphragm frames to the top of the tall wall, and there is no load path shown at the short wall. There is no detail provided for the condition where the truss is parallel to the wall (section perpendicular to the trusses). Please provide. Reference AAC section 23.10.104.8. WAB – 9/18/2012
Comment remains. This is still not clear. WAB – 10/18/2012
2. LATERAL DESIGN
Reference the lateral design in the calculations. Please provide the following:
A. For the N/S direction, the average wall height appears to be 15.33’. Please verify. Please note that if there is an end truss that is to be used to collect the load to the shear wall below, please indicate this on the drawings. In this case the height of the wall can be taken as 9’; however there could be additional uplift at the ends of the wall from overturning in the truss.
Item resolved. Response accepted. WAB – 9/18/2012
B. For the E/W direction, the height of the taller wall appears to be 21.67’ tall. Please verify.
C. Per the analysis the east shear wall has 382 lbs/ft. Please indicate this wall to have 3X sill plates or show that the 2008 NDS Special Design Provisions for Wind and Seismic (SDPWS) section 4.3.6.4.3 is met or show that there are twice as many anchor bolts provided as is needed.
3. SEISMIC SEPARATION
Please provide substantiating data showing the seismic separation provided between the office and the hanger is sufficient. Reference ASCE 7-05 section 12.12.3.
Comment resolved. An 8” seismic joint has been provided. WAB – 9/18/2012
4. LATERAL AT FOUNDATION
Reference the drawings. The original designed called for cross ties on the frames to transfer the lateral forces at the foundation level. The new design appears to use the slab-on-grade to resist these forces. Where slabs-on-grade are used to resist seismic forces they must be indicated as structural diaphragms on the drawings, and design to meet ACI 318-08 section 21.12.3.4. The main issue here is to prohibit or control saw cutting of the slab (to ensure reinforcement is not accidentally cut), and to ensure that reinforcement is provide across construction joints. Please provide this information on the drawings.
Comment resolved. Slab will not be saw cut and no construction joints will be used. WAB – 9/18/2012
5. UPLIFT DESIGN
Please provide uplift ties for the trusses, and ensure a proper load path into the studs below, i.e. if the tie down is installed on the non sheathed side, SP2 or similar tie must be provided from the studs to the plate or one of the hold downs that frame from the truss to the studs must be provided. Reference IBC section 1604.9.
Comment resolved. Response accepted. WAB – 9/18/2012
6. STATEMENT OF SPECIAL INSPECTIONS
Please revise the statement of special inspections to include the inspection requirements for wood and soils. Reference IBC section 1705.
The following comments remains from the original review.
7. BRACE SIZE
Reference the metal building drawings. Please clarify where the brace sizes are indicated in the drawings. Reference AAC section 23.10.104.8.
Comment remains. No response appears to have been provided. WAB – 9/18/2012
Comment remains. This information had been provided, but the reviewer could not locate it in the file. Please provide this information again. WAB – 10/18/2012
Comment resolved. This information has been provided. WAB – 11/15/2012
8. BRACE CONNECTION DESIGN
Reference the metal building calculations. Please clarify where the brace connection design is located. Brace connections must be designed to meet AISC 341-05 sections 7.2 and 14.4.
Comment remains. Please provide hand calculations showing the capacity determined by the software is correct. The reviewer was unable to duplicate the capacities indicated. Please also note that if the software only checks the limit states shown in the document provided for hillside washer connection design then it is not provide a complete check of the connection. Bending of the web plate must also be verified, and would likely need to be verified at 5 locations; at the inside web to flange connection, the outside web to flange connection, the web to base plate connection, at the location of the application of load, and possibly at the location of reverse bending within the web above the connection point. Please verify that the software considers bending in the plate.
Please also note that the brace detail must be revised to show the backup plates that are required. WAB – 10/18/2012
Comment remains. As indicated in the original comment, the reviewer was not able to independently verify the capacity the software determined for the web. It is also not clear if the software only checks the limit states of Weld Failure of Web-Flange Connection, Direct Shear Fracture of Web Plate, Punching Shear Fracture of Web Plate, and Tensile Fracture of Web Plate. If so it is not providing a complete check of all limit states such as bending of the web plate. Nothing in the response provided additional information on either of the issues brought up in the comment. The response was basically a summary of what the computer software indicated. WAB – 11/15/2012
9. BRACE DESIGN
Reference the metal building calculations. Please clarify what sheet the braces have been designed on. If the braces are cables they must be designed per ASCE 19-96.
Comment resolved. This information has been provided. WAB – 10/18/2012
10. DRAWINGS
Please note that much of sheet S-3 is not legible. Please submit a copy that is. Reference AAC section 23.10.104.8.
Comment resolved. This has been clarified. WAB – 10/18/2012
Please provide a written response to the comments and include one copy of additional or revise calculations, and two copies of additional or revise drawings. While not required it is extremely helpful to the reviewer if the response indicates where in the submittal each comments has been addressed.
All submittals should be sent to the permit manager.
