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20071218111830.pdfDecember 17, 2007 Ann Bullis, Plan Reviewer and Assistant Code Official Development Services Department 121 5th Avenue North, Second Floor Edmonds, Washington 98020 Dear Ann Bullis: This is a plan review on REVISED STRUCTURAL PLANS for the: Project Name: Old Mill Town — Phase I Revisions — 5th Ave So. at Dayton St. Plan Review Nq: 1124-407 (Your Pian Check Number was BLDG: 2006-0845) Codes: Structural Only Revisions; '03 IBC; ASCE &-02;'01 NDS; '02 ACI; 3 ksf bearing soil PREFACE: This letter -report contains various comments on the submitted plans for potential changes to the design Standards in the Codes indicated above. I have specified a general area of concern in each comment, along with a specific location on a plans and a Code -specific Section in which the provision is found. I assume that the designers will to read entire Code provisions rather than my having to duplicate it in the letter. Unless specified otherwise, references are to the'03 IBC and ASCE 7-'02. Even though this letter -report is addressed to you as advisory recommendations, Ann, the designers of record need to directly address and resolve the issues. Generally, changes will be required to plans and specifications. If, the engineer disputes any of my points or has an alternate way of complying with it; he or she should provide both of us written responses addressing each disputed comment. The Engineer should indicate what he or she intend to do about potential discrepancies and where solutions will be found on revised specifications, plans, change- orders or otherwise. They should also provide a cloud around changes. That way, we will be able do a final review in a more efficient and expedient manner. Specific Fire -Safety Issues: 1. The use of intumescent paint on structural steel requires an alternate design under Section 703.3 and 104.11. Such intumescent "paint" is not universal or generic; they have various listings by U.L and other labs, for a specific manufacturer's design. Enclosed is ICC ES Acceptance Criteria " 23 for such fire resistance coatings. 2. Structural plans show the 2nd story "roof' over with a 100 psf live load. If so, there should be two means of egress off of it. Section 1014.1 and Table 1004.1.2 General and Specific Structural Comments 4. Field welding is called out for the job -fabricated column base and embed plate shown on the lower portion of Section View 5151 to the left; special inspection should be specifically called out for field welding in addition to that for the moment frames. Sections 1704.3.1 5. Presumably the "roof loads" in the Structural Notes/S1 that are listed with a 100 psf live load, are for its (temporary?) use as an assembly deck and should be so listed. Also, all other plans must reflect this change. 6. But the notes on Sheets A3.XX and A4.XX, should also account for a future condominium floor plus, partition loading, and perhaps from some other weight. It is clearer to call this addition plainly a story instead of a "roof' loading. See Section 1607.11.2.2, 2nd sentence. No review was made at this time for the future third story. Ann Bullis, City of Edmonds Old Milltown Renovation and Repair Plan Review Number 1924-407 December 11, 2007 Page 2 of 6 7. The Quality Assurance Plan and Other Structural Notes: a. There are special inspection notes scattered throughout the structural notes, which should really be part of the QA Plan, per se. Sections 1707.1 b. Subject to your judgment, it may be okay to leave them where they are, but they should definitely indicate all of them in the Contractor's QA Plan, to ensure they are aware of what is expected of them. c. Shear Wall # 2 has to be added to the special inspection list too. Section d. That Contractor's QA plan needs to be a formal submittal before the permit is issued and before any work is started. I sent you a form that you may want them to use to do this function. However, they need the written summary from the registered -design - engineer -in -responsible -charge, or RDP for the first part of the list. e. The RDP also has to include information about mechanical and electrical systems as stated in Section 1707 and ASCE 7: i. Anchorage of any sprinkler piping including the main line, which exceeds 3" in diameter. Section 1707.7.1 and ASCE 7 Section 9.6.1.5, 1p = 1.5. ii. However, the architect and mechanical/plumbing engineer have to revise any specifications and acknowledge and follow ASCE 7 Section 9.7.3.11.2, which basically prohibits prescriptive connections in NFPA Standard 4 13 from being used. They need to be designed by regular ASCE 7 Sections 9.6.1.6 - 9.1.6.7 f. The specific required testing contained in the AISC Standard # 341 needs to be identified and detailed in the plan. Section 1708.4. It can be downloaded from: http://www.aisc.org/Content/NavigationMenu/ePubs/freePubsl /Seismic_ Resources/Seis mic Resources.htm and relevant specific details need to be specified in the plan documents g. The RDP also has to detail the specific required AWS D1.1 acceptance criteria for nondestructive testing. Section 1708.4 h. Periodic special inspection is required for plywood nailing in Shear wall # 2, and its bolting, anchoring, drag struts, and hold-downs. Sections 1704.6, 1704.1, and 1703. i. Adhesive and mechanical bolts resisting seismic loads are required (and were required in January 2006) to be listed for use in cracked concrete. Section 1912 L The post -installed Powers Company "Power -Stud" anchors specified on Sheet S-1 must be justified with an ICC Evaluation Service Report for compliance in cracked concrete or be replaced with those that do comply. All manufacturers were still working with the ICC to establish criteria for approval in 2006, which was completed in June and manufacturers starting doing the required tests in mid -2006. To date only two mechanical anchors, Simpson Strong-BoltTM and Hilti KB -TZ; comply with Section 1912. And Hilti just received an ICC ESR for a new complying epoxy anchor, Hilti HIT -RE -500 -SD. One of those anchors needs to be specified rather than those shown in the notes on Sheet S1. Ann Bullis, City of Edmonds Voluntary Upgrade of Foundation System Plan Review Number 1924-407 December 17, 2007 Page 3 of 6 iii. Additionally, the footings -to -concrete -wall dowel connections shown on Sections 2, 3 & 5151 and bolts -to -existing -concrete -wall on Sections 1 & 8/S10 need to use the Hilti epoxy design. iv. Note that these presently non -complying -anchors are spread through the plan sheets and all need to be removed and replaced with those which do comply. j. The note on the right side near the bottom of Sheet S1 should specify exactly what standard the pressure -preservative Hem -Fir lumber is supposed to be meeting?' 8. Geotechnical and foundation comments: a. I didn't get the soils report by Zipper Zeman Associates mentioned on Sheet S-1. Therefore, I will rely on you to verify soil data and other details. At a minimum, they would need to have provided the normal soils report criteria in Section'! 802.4. b. However, the report should have also included a determination of lateral pressures due to earthquake motions on retaining walls shown in details 1 & 3/S13. The calculations mention a uniform lateral load of "12H" for the design of such walls, so could you verify that value? Section 1802.2.7 9. In line with Structural Comment # 3 above, the distribution of the seismic shear for a new 3rd story has to be estimated by assuming a typical 3rd story condo floor and using the usual design provisions and procedure for seismically distributed loads both horizontally and vertically all the way to the ground floor. ASCE 7-02 Section 9.5.2.1. There was some attempt to do that on Calculation Sheets D1 to D6, but for some reason all 3 levels above the ground floor are not accounted for on Calculation Sheets L7 to L9. 10. But note that the new condominium that is contemplated may cause the entire building to be modified to comply with the building code at the time it is proposed. Section 1614.1.1. Stated another way, there is no guarantee that condos, or other uses will be allowed. 11. The 100 psf, the designer shows for the (2"d story roof?) "deck" needs to be studied since that value is associated with assembly occupancies. The gross roof deck, before the third story is placed over it, would be (113')2 = 12,770 s.f. By IBC Table 1004.1.2, the floor area per occupant is 15 s.f./occupant. If the assembly loading exceeds 300 occupants on the roof, it would be 4,500 s.f., and would require an importance factor of 1.5 be applied to seismic force levels. ASCE 7 Table 9.1.4. Even if only part of the roof is intended to be used for this type of use, how will the number of people be effectively controlled? 12. The maximum height of the concrete wall in Section 1/S2 needs to be defined. 13. The existing concrete walls proposed as shear wall shown on Details 81510,10155, et al: a. When were they constructed and what reinforcement size and spacing was used? This is needed to ensure that they are reinforced enough to be considered a special reinforced concrete shear wall now; the minimum was (under the UBC) and still is 0.0025 not to exceed 18" o.c. ACI -02 Section 21.7.2.1. Otherwise they are considered ordinary reinforced concrete structural walls and can't be used in SDC D applications. b. But since some concrete walls also exist — see Sheets S5 and S10 and detail 7156 -- if calculated shear loads coming to these walls are increased by more than 5% (over 2003 ' WWPA's Hem -Fir Species Facts, 03-1997: http:llwww2.wwpa,argfWESTERNSPECIESIHemFirltabid/299/Default.aspAtreated Ann Buflis, City of Edmonds Voluntary Upgrade of Foundation System Plan Review Number 1124-407 December 17, 2007 Page 4 of 6 IBC levels including the future 3rd story addition) and they don't have the proper resistance, they to be strengthened somehow or be decoupled. c. Also, since other interior transverse and longitudinal concrete shear walls are to be demolished and new openings are made in the exterior walls the building, there may have less 5% less strength than before even with the new braced frames and wood shear walls. By The Section 1614.3, those alterations would be required to comply completely with today's code -- unless it can be demonstrated that all items in the exception to that section have been shown to be satisfied. 14. New steel braced frames, concrete walls, and wood shear walls: a. The single steel diagonal brace on the ground floor shown in Section 21A4.0 is not strictly specified in ASCE 7 Table 9.5.2.2: i. Strictly speaking, that condition may cause a "soft -story' condition, as defined in ASCE 7 Table 9.5.2.3.3 to happen, which requires the engineer to provide an alternative design to account for it. Section 9.5.2.5.1 ii. ASEC 7-02 Section 9.8 (pg. 174) "specifies" the use of AIS1 "Seismic Provisions for Structural Steel Buildings" 1997 with Supplement # 2. 1 would, however, highly recommend that the designers use the more up-to-date '06 AISI one with the same name, but with a new Supplement # 1. It can be downloaded from AISI's website for free. iii. Basically, it requires an effective response reduction coefficient, R of - 3, with over strength coefficient applied to columns and collectors of -- 4.0. iv. Since this R = 3 would have to control for both directions in this S.D.C. D area, the seismic forces would also have to increase for the whole building by (R=)513 = 1.67 times in addition to the redundancy factor of 1.5. Section 9.5.2.2.2.1 v. The SEAOC IBC Structural Design Manual # 2 doesn't recommend single braces to be used in S.D.C. D because of the significant uncertainty about the magnitude of the seismic forces it may have to resist not counting the extra forces from a potential extra story. b. The other braced frames and concrete shear walls: i. Deformational compatibility needs to be addressed for the fames and concrete shear walls on the first floor, Line # 8. ASCE Section 9.5.2.2.4.3 ii. How are lateral loads dragged into the 15t story concrete wall along line 5152? iii. There is apparently an elevator pit hole in the floor over this concrete wall on line 5 between lines G and H on Sheets S2 and S3? How does this work? iv. 1 don't understand the relationship between Section 7155 and 21512 for braced frame " 1. Something seems to be missing or the references are incorrect. v. However, how can the circular steel columns, even with a new W6X16 strut, safely transfer lateral loads, even if it is supposed to be a frame? In fact, this may be a soft or weak story condition and needs to be studied relative to ASCE 7 Section 9.5.2.5.1. ASCE Table 9.5.2.3.3 vi. Out of plane bracing and fire protection for the steel should surely be the minimums to keep this concrete wall from collapsing in a seismic or fire event. Ann Bullis, City of Edmonds Voluntary Upgrade of Foundation System Plan Review !Number 9124-407 December 17, 2007 Page 5 of 6 IBC Section 714.2.1 and ASCE 7 Section 9.5.2.6.3.2 vii. Also, how is this wide -flange beam actually connected to the circular column? viii. It would seem that cross -ties should be provided for the framing shown on Section 91S5 too. c. The wood shear resisting systems: i. There should also be floor panel boundary nailing shown into the PSL 91/4" x 11" beam under the floor plate as shown on Detail 3/S10 as well as the vertical wall plywood. Table 2306.3.1 ii. However, the exterior sheets for the shear walls on top of this PSL beam and decking would have to be over 8' long if it is only going to be nailed to the floor plate and bottom of the beam. More than likely there should be a "belly band" strip needed to cover the beam, with the edge nailing on that normal length panel above it into the bottom plate as shown. iii. The "mini -diaphragms" for the roof and floor diaphragms shown on Detail 8155 for the EW direction may be okay but more details are required: (1). Note that the strength -design -forces for the steel elements in the wall anchorage system have to be 1.4 times the calculated force. (2). See ASCE 7, Sections 9.5.2.6.3.2 along with Section 9.5.2.6.4.1. Note that boundary nailing is required along the "back side" of the sub - diaphragm portion in the NS direction to form separate entities. iv. For the NS direction at each exterior wall Details 5 and 6 are almost perfect except that they need to show boundary nailing over those PSL rafter and floor joist struts. v. Cross ties should be specified for the present roof and floor on line G between 0 and 2. vi. Roof uplift from wind should be studied for the overhang joist and its extension back to Line 2 shown in Section View 11510. That area is closest to a partially enclosed structure and uplift anchors seem to be needed to resist the net uplift. ASCE 7 Sections 6.2, definition of partially enclosed, Sections 6.5.11.4 and 6.5.12.2.1 vii. What size anchors are to be used in the straps shown on Section 8/S6? viii. The cross reference near Grid G-0 on Sheet S4 for "XIS" needs to be defined. 15. The method of adhering or tying the stone veneer specified on Section 11A4.2 should be shown on the architectural or structural drawings. Section 1405.6 or 1405.7 CLOSING The designers should revise the plans and specifications and resubmit the as explained in the beginning of this letter. Thank you once more for the opportunity to be of service. An invoice for this review based on an hourly rate will follow under separate cover. Please call or write, if you have any questions or concerns. Ann Bullis, City of Edmonds Voluntary Upgrade of Foundation System Plan Review Number 1124-407 December 17, 2007 Page 6 of 6 Sincerely, Jerry J. Barbera, M.S.C.E. and P.E. Construction Codes Consultant Encl: ]CC ES Acceptance Criteria # 23, and ICC ES Reports;