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HomeMy WebLinkAboutCA_Structural_Analysis_170403_v1 651 W. Galena Park Blvd., Suite 101 / Draper, UT 84020 / (801) 990-1775 / www.vectorse.com Project Number: U1194-105-171 April 3, 2017 Centerline Solutions 3320 South Bay Road NE Olympia, WA 98506 ATTENTION: Bryan Underhill REFERENCE: SE02505C - High Renton H20 / US West – L1900 3410 NE 12th St. – Renton, WA 98056 Structural Review of Proposed Equipment Modifications Dear Bryan, Per your request, we have reviewed the construction drawings prepared by your office for the proposed removal of (3) existing FXFB’s (RRUs) and (6) TMAs and the addition of (3) new FHFB’s (RRUs) and (3) NEW TMAs that are mounted on existing antenna pipes attached to a existing water tank. We have also reviewed previous structural calculations for panel antenna and equipment modifications prepared by Cornerstone Engineering, Inc. (dated 06/15/12), a structural analysis report prepared by CG Engineering (dated 09/17/15), as-built drawings prepared by B. J. Thomas, P.E. (dated 05/05/16, Rev 9) and site-walk photographs provided by your office (dated 03/06/13). Please be advised as follows: Based upon our calculations and review of the documents noted above, we conclude that the existing equipment mounts and attachments are adequate to support the loads associated with the proposed equipment. Our conclusion is based on the fact that the gravity loads are not increasing by more than 5% (satisfying Section 807.5 of the 2015 IEBC) and the lateral loads are not increasing by more than 10% (satisfying Section 807.4 of the 2015 IEBC). In addition, the lateral and gravity loads associated with the proposed equipment are minor when compared to the loading associated with the overall structure and will not significantly affect the existing water tank, railing, or catwalk. The recommendations above are provided based upon calculations prepared by our office and information the client provided. The analysis and conclusions described above are limited to the members included in this report only and are based on the assumption that the structure was properly designed and constructed, and has been properly maintained. Vector Structural Engineering makes no claim as to the correctness of the original design or the current condition of the structure, which is assumed to be in good condition, free of damage or deterioration. The contractor shall verify the suitability of the existing mounts and the condition of the existing structure and shall notify Vector immediately should any damage, deterioration or discrepancies between the as-built condition of the existing structure and the assumed condition described in this report and on the construction drawings be found. We hope this meets your needs. If you have any further questions regarding this matter, please call this office at your convenience. Very truly yours, VECTOR STRUCTURAL ENGINEERING, LLC WA Firm License Number: 2202 Wells L. Holmes, S.E. Project Engineer WLH/cnm Enclosures 04/03/17 RECEIVED 05/12/2017 striplett BUILDING DIVISION B17002126APPROVED BUILDING DIVISION By: Alan Findlay Date: 05/25/2017 Note: This approval is for structural review only. THIS SET OF APPROVED PLANS MUST BE ON THE JOB AT ALL TIMES DURING CONSTRUCTION. THIS BUILDING IS NOT TO BE OCCUPIED UNTIL AFTER FINAL INSPECTION BY THE RENTON BUILDING DIVISION AND RECEIPT OF CERTIFICATE OF OCCUPANCY. APPROVAL SHALL NOT BE CONSTRUED AS THE AUTHORITY TO VIOLATE OR CANCEL ANY PROVISIONS OF CODES, ORDINANCES, OR OTHER REGULATIONS ENFORCED BY THIS CITY. N:\Logos\VectorLogo.gif JOB NO.:U1194-105-171 PROJECT:HIGH RENTON H20 / US WEST Design Criteria: Code:Structural design is based on the International Building Code, 2015 Edition (with Local Amendments) Wind:Basic wind speed = 110 mph (3-second gust) per the ASCE 7-10 standard Risk category / Structure class: IV Wind exposure: B Topographic category: 1 Crest height: 0 ft Ice:0.25" radial ice @ 30 mph basic wind speed (3-second gust) per the TIA-222-G standard Seismic:Seismic loads are based on the International Building Code, 2015 Edition (with Local Amendments) and the TIA-222-G standard Seismic importance factor, I = 1.5 Risk category / Structure class: IV Mapped spectral response accelerations:SS =1.42g S1 =0.534g Site class: D Spectral response coefficients:SDS =0.947g SD1 =0.534g Seismic design category: D Basic seismic-force-resisting-system: Cantilever Element: Braced above its center of mass General Notes: 1 2 3 4 5 Structural Steel: 1 All structural steel code checks based on the AISC-LRFD, 3rd Edition per the TIA-222-G standard 2 All steel pipe to be per ASTM A53 GR. B (35 KSI), U.N.O. 3 All other structural steel shapes & plates shall be per ASTM A36, U.N.O. 4 All bolts for steel-to-steel connections shall be per ASTM F3125 GR. A325 U.N.O. 5 All bolted connections shall be tightened per the "turn-of-nut" method as defined by AISC. 6 7 The contractor shall verify dimensions, conditions and elevations before starting work. The engineer shall be notified immediately if any discrepancies are found. The typical notes and details shall apply in all cases unless specifically detailed elsewhere. Where no detail is shown, the construction shall be as shown for other similar work and as required by the building code. These calculations are limited to the structural members shown in these calculations only. The contractor shall be responsible for compliance with local construction safety orders. Approval of shop drawings by the architect or structural engineer shall not be construed as accepting this responsibility. All structural framing members shall be adequately shored and braced during erection and until full lateral and vertical support is provided by adjoining members. All welding shall be performed by certified welders in accordance with the latest edition of the American Welding Society (AWS) D1.1 All steel surfaces shall be galvanized in accordance with ASTM A123 and ASTM F2329 standards, thoroughly coated with a zinc-rich primer, or otherwise protected as noted on the structural drawings. Page 1 of 7 RECEIVED 05/12/2017 striplett BUILDING DIVISION B17002126 N:\Logos\VectorLogo.gif JOB NO.:U1194-105-171 PROJECT:HIGH RENTON H20 / US WEST SUBJECT:ANTENNA MOUNT LOADS Label:Wind per: On a: at 111.5 ft AGL Load Combinations: TIA-222-G ASCE 7-10 Typ. Sector Previous Loading Other Point Loads SBNHH-1D65C Panel AntennasFXFB RRUFRLB RRUUnit Weight (lbs) 49.6 55 59.5 Quantity ()1 1 1 Height (Y-DIR) (in) 96 19.3 15.75 Width/Diameter (X-DIR) (in) 11.9 22 15.75 Depth (Z-DIR) [Blank if Round] (in) 7.1 5.2 5.9 XY Plane Projected Area (ft2)7.93 2.95 1.72 YZ Plane Projected Area (ft2)4.73 0.70 0.65 Wind Force per Unit: X-DIR Design Wind Pressure (psf) 58.1 48.6 48.6 Z-DIR Design Wind Pressure (psf) 65.5 50.8 48.9 Unfactored: X-DIR Wind Load (lbs) 461 143 84 Z-DIR Wind Load (lbs) 310 35 32 Factored: (1.0W) X-DIR Wind Load (lbs) 461 143 84 Z-DIR Wind Load (lbs) 310 35 32 Seismic Force per Unit: Unfactored: Lateral (lbs) 112.7 125.0 135.2 Vertical (lbs) 9.4 10.4 11.3 Factored (1.0E): Lateral (lbs) 112.7 125.0 135.2 Vertical (lbs) 9.4 10.4 11.3 Line Loads Antenna Mount PipeShape 3" Std. Pipe Length (ft)11 Quantity 1 Orientation (Axis)Y Weight (plf) 7.576 Total Weight (lbs) 83 Wind Force: X-DIR Design Wind Pressure (psf) 28.2 Z-DIR Design Wind Pressure (psf) 28.2 Unfactored: X-DIR Wind Load (plf) 8.2 Z-DIR Wind Load (plf) 8.2 X-DIR Wind Load (lbs) (delete value 90.4 Z-DIR Wind Load (lbs) if shielded) 90.4 Factored (1.0W) X-DIR Wind Load (lbs) 90.4 Z-DIR Wind Load (lbs) 90.4 Seismic Force: Unfactored: Lateral (plf) 17.2 Vertical (plf) 1.4 Factored (1.0E): Lateral (plf) 17.2 Vertical (plf) 1.4 Page 2 of 7 RECEIVED 05/12/2017 striplett BUILDING DIVISION B17002126 N:\Logos\VectorLogo.gif JOB NO.:U1194-105-171 PROJECT:HIGH RENTON H20 / US WEST SUBJECT:ANTENNA MOUNT LOADS (ANTENNA MOUNT LOADS CONT'D) Dead Load, D: Total Weight of Components:Wp =247 lb Wind Load, W: Unfactored Wind Force:VX =779 lb Factored: 1.0 779 lb Wind Controls VZ =467 lb 1.0 467 lb Seismic Load, E:Consider Seismic: Yes Occupancy Category: IV Fa =1.0 R =1.0 Fp,min /W= 0.426 Seismic Design Category: D Fv =1.5 ap =2.5 Fp,max /W= 2.272 Ip =1.50 SMS =1.420 z (ft)= 1.0 Site Class: D SM1 =0.801 h (ft)= 1.0 Fp, lateral /W= 2.272 Ss =1.420 SDS =0.947 z/h = 1.0 S1 =0.534 SD1 =0.534 Fp, vertical /W= 0.189 Unfactored Seismic Force:Fp,trans = 562 lb Factored: 1.0 562 lb Fp,long = 562 lb 1.0 562 lb Seismic Controls Fp,vert = 47 lb 1.0 47 lb * VX = * VZ = * Fp,X = * Fp,Z = * Fp,Y = Page 3 of 7 RECEIVED 05/12/2017 striplett BUILDING DIVISION B17002126 N:\Logos\VectorLogo.gif JOB NO.:U1194-105-171 PROJECT:High Renton H20 / US West SUBJECT:ANTENNA MOUNT LOADS Label:Wind per: On a: at 111.5 ft AGL Load Combinations: TIA-222-G ASCE 7-10 Typ. Sector Proposed Loading Other Point Loads SBNHH-1D65C Panel AntennasFHFB RRUFRLB RRUTMAT1921B78-21A TMAUnit Weight (lbs) 49.6 51 59.5 17.6 Quantity ()1 1 1 1 Height (Y-DIR) (in) 96 23 15.75 9.1 Width/Diameter (X-DIR) (in) 11.9 12.6 15.75 8.7 Depth (Z-DIR) [Blank if Round] (in) 7.1 7.8 5.9 4.1 XY Plane Projected Area (ft2)7.93 2.01 1.72 0.55 YZ Plane Projected Area (ft2)4.73 1.25 0.65 0.26 Wind Force per Unit: X-DIR Design Wind Pressure (psf) 58.1 48.6 48.6 48.6 Z-DIR Design Wind Pressure (psf) 65.5 49.4 48.9 48.6 Unfactored: X-DIR Wind Load (lbs) 461 98 84 27 Z-DIR Wind Load (lbs) 310 62 32 13 Factored: (1.0W) X-DIR Wind Load (lbs) 461 98 84 27 Z-DIR Wind Load (lbs) 310 62 32 13 Seismic Force per Unit: Unfactored: Lateral (lbs) 112.7 115.9 135.2 40.0 Vertical (lbs) 9.4 9.7 11.3 3.3 Factored (1.0E): Lateral (lbs) 112.7 115.9 135.2 40.0 Vertical (lbs) 9.4 9.7 11.3 3.3 Line Loads Antenna Mount PipeShape 3" Std. Pipe Length (ft)11 Quantity 1 Orientation (Axis)Y Weight (plf) 7.576 Total Weight (lbs) 83 Wind Force: X-DIR Design Wind Pressure (psf) 28.2 Z-DIR Design Wind Pressure (psf) 28.2 Unfactored: X-DIR Wind Load (plf) 8.2 Z-DIR Wind Load (plf) 8.2 X-DIR Wind Load (lbs) (delete value 90.4 Z-DIR Wind Load (lbs) if shielded) 90.4 Factored (1.0W) X-DIR Wind Load (lbs) 90.4 Z-DIR Wind Load (lbs) 90.4 Seismic Force: Unfactored: Lateral (plf) 17.2 Vertical (plf) 1.4 Factored (1.0E): Lateral (plf) 17.2 Vertical (plf) 1.4 Page 4 of 7 RECEIVED 05/12/2017 striplett BUILDING DIVISION B17002126 N:\Logos\VectorLogo.gif JOB NO.:U1194-105-171 PROJECT:High Renton H20 / US West SUBJECT:ANTENNA MOUNT LOADS (ANTENNA MOUNT LOADS CONT'D) Dead Load, D: Total Weight of Components:Wp =261 lb Wind Load, W: Unfactored Wind Force:VX =760 lb Factored: 1.0 760 lb Wind Controls VZ =506 lb 1.0 506 lb Seismic Load, E:Consider Seismic: Yes Occupancy Category: IV Fa =1.0 R =1.0 Fp,min /W= 0.426 Seismic Design Category: D Fv =1.5 ap =2.5 Fp,max /W= 2.272 Ip =1.50 SMS =1.420 z (ft)= 1.0 Site Class: D SM1 =0.801 h (ft)= 1.0 Fp, lateral /W= 2.272 Ss =1.420 SDS =0.947 z/h = 1.0 S1 =0.534 SD1 =0.534 Fp, vertical /W= 0.189 Unfactored Seismic Force:Fp,trans = 593 lb Factored: 1.0 593 lb Fp,long = 593 lb 1.0 593 lb Seismic Controls Fp,vert = 49 lb 1.0 49 lb RATIO OF PROPOSED LOADING TO CURRENT LOADING Gravity Loads: 105% Front Wind: 98% Side Wind: 108% * VX = * VZ = * Fp,X = * Fp,Z = * Fp,Y = Page 5 of 7 RECEIVED 05/12/2017 striplett BUILDING DIVISION B17002126 ASCE 7 Windspeed ASCE 7 Ground Snow Load Related Resources Sponsors About ATC Contact Search Results Query Date: Thu Mar 30 2017 Latitude: 47.5029 Longitude: -122.1730 ASCE 7-10 Windspeeds (3-sec peak gust in mph*): Risk Category I: 100 Risk Category II: 110 Risk Category III-IV: 115 MRI** 10-Year: 72 MRI** 25-Year: 79 MRI** 50-Year: 85 MRI** 100-Year: 91 ASCE 7-05 Windspeed: 85 (3-sec peak gust in mph) ASCE 7-93 Windspeed: 70 (fastest mile in mph) *Miles per hour **Mean Recurrence Interval Users should consult with local building officials to determine if there are community-specific wind speed requirements that govern. WINDSPEED WEBSITE DISCLAIMER While the information presented on this website is believed to be correct, ATC and its sponsors and contributors assume no responsibility or liability for its accuracy. The material presented in the windspeed report should not be used or relied upon for any specific application without competent examination and verification of its accuracy, suitability and applicability by engineers or other licensed professionals. ATC does not intend that the use of this information replace the sound judgment of such competent professionals, having experience and knowledge in the field of practice, nor to substitute for the standard of care required of such professionals in interpreting and applying the results of the windspeed report provided by this website. Users of the information from this website assume all liability arising from such use. Use of the output of this website does not imply approval by the governing building code bodies responsible for building code approval and interpretation for the building site described by latitude/longitude location in the windspeed load report. Sponsored by the ATC Endowment Fund • Applied Technology Council • 201 Redwood Shores Parkway, Suite 240 • Redwood City, California 94065 • (650) 595-1542 Map data ©2017 GoogleReport a map error Page 6 of 7 RECEIVED 05/12/2017 striplett BUILDING DIVISION B17002126 Design Maps Summary Report Building Code Reference Document Site Coordinates Site Soil Classification Risk Category User–Specified Input 2012/2015 International Building Code (which utilizes USGS hazard data available in 2008) 47.5029°N, 122.173°W Site Class D – “Stiff Soil” I/II/III USGS–Provided Output SS = 1.420 g SMS = 1.420 g SDS = 0.947 g S1 = 0.534 g SM1 = 0.801 g SD1 = 0.534 g For information on how the SS and S1 values above have been calculated from probabilistic (risk-targeted) and deterministic ground motions in the direction of maximum horizontal response, please return to the application and select the “2009 NEHRP” building code reference document. Although this information is a product of the U.S. Geological Survey, we provide no warranty, expressed or implied, as to the accuracy of the data contained therein. This tool is not a substitute for technical subject-matter knowledge. Page 7 of 7 RECEIVED 05/12/2017 striplett BUILDING DIVISION B17002126