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Report (2) BRADFORD CONRAD R�an CROW ENGINEERING CO. ACza CIVIL • STRUCTURAL • MECHANICAL ENGINEERS November 2,2009 Building Official City of Tigard 13125 SW Hall Blvd Tigard,OR 97223 RE:Westgate Baptist Church Retractable Platform—Permit No.BUP2009-00155 Subject: Welding Special Inspections of platform frame Special Inspections as required by IBC Section 1704 were not provided during the fabrication of the platform structure. Carlson Testing provided an after fabrication visual inspection of the painted welds (report attached). They indicate that the connections meet the detail criteria and the weld profiles are acceptable and appear to have no discontinuities. An after the fact visual inspection of painted welds, however, does not fully satisfy the special inspection requirements. Proposed Remedy: 1. All welded connections were evaluated for stress levels of the welds under full dead plus live load conditions. The welds for all but two of the connection types are stressed below 50% of the available weld capacity.None of the welds are critical seismic connections. 2. We propose accepting the welds stressed at 50% or below based on the visual observation of the painted welds. 3. The two connection types that are stressed above 50% are the frame top chords to center pivot connection plate and the brace connection plate to the base of the center pivot. Ref Details A/7010-02 and C/7010-02.These connections are stressed to approximately 80%of the allowable of capacity per the 2005 ANSI/AISC 360-05 Specification for Structural Steel Buildings. 4. We propose a load test in accordance with AISC 360-05 Appendix 5 section 5.4 to verify the strength of the critical connections.The load test will consist of applying a 2800 lb load on the end 3 feet of each of the four frames. Each frame is to be tested individually, not all at the same time. Since the test is only intended to test the specific welds under consideration,the entire methodology of section 5.4 will not be implemented. Namely, structural deformations will not be measured or recorded. The connections of concern will be visually inspected.The applied load represents 1.2 D+1.6 L.The worst case for 40 psf LL with the jacks in the up position or 100 psf with the jacks lowered will be represented by this test. 5. Test Procedure: a. All bolted connections are to be tensioned prior to the load test. b. Do Not lower the jacks. c. For each load point: i. Stack one 700 lb pallet of material on the platform at the location shown on the attached sketch. Observe the structure for deformation or signs of distress. Specifically,inspect the welds of concern. ii. Repeat for three additional pallets, stacked one above the other, observing the structure after each increment of load. iii. Hold the load for one hour. 9925 S.W.Nimbus Avenue•Suite 110•Beaverton,Oregon 97008-7387•Phone(503)213-2013 Facsimile(503)213-2018•Email inforequest @bccengineering.com•www.bccengineering.com Westgate Baptist Church November 2,2009 Retractable Platform Load test proposal iv. Re-inspect the connections. v. Remove all load. d. Repeat the procedure for each load point. 6. If no distress in the connections is observed, the test will be considered successful and we will recommend the structure be accepted. ...¢UCTUR4�EO _ S� PROfff��/ GiNe 11 20, ; vOti✓GAY '/ 0Q- 4, BRA0F Renewal Date: 12/31/2009 Date Signed: 11-02-09 cc. Brian Dutton 0 Page 2 BRADFORD t z`_= CONRAD tea,-. CROW ENGINEERING CO. CIVIL • STRUCTURAL • MECHANICAL ENGINEERS -November 17,2009 Building Official City of Tigard • 13125 SW Hall Blvd Tigard, OR 97223 • RE:Westgate Baptist Church Retractable Platform—Permit No. BUP2009-00155 Subject: Load Testing Results in lieu of Welding Special Inspections of platform frame A load test was performed on November 12, 2009 in accordance with the Test Procedure provided in the attached letter.The load was applied manually using 80 lb bags of premix concrete. The load test was video recorded and reviewed. I visited the site on Friday November 13,2009 and observed the structure after the test was complete and all load was removed. The test procedure was acceptable as done. No distress was observed during or after the test. Based on the results of the test, Carlson Testing's visual inspection report, and my observations, I recommend that the structure be accepted as constructed. pour Res.ectfully, � 14323 / )11#1, , / John F. Bradfor,/ E oREG ;v President / � ��, 1`� ,4 �Y f3 \q.,®S' cc::Brian Sutton F SRO FF‘TWAI,DATE:(Z.4 l-cr' J • 9925 S.W.Nimbus Avenue•Suite 110.Beaverton,Oregon 97008-7387•Phone(503)213-2013 Facsimile(503)213-2018•Email inforequest @bccengineering.com•www.bccengineering.com • • Inc. lain Office Salem Office Bend Office Carlson Testing, Inc J305w Hrrn_rAer Salem Aon Sr NE F+0?S OB RAr RAKlf • h n e OR 1654- Salem OR 9730l Brnrf.OR 97.0? Phnne.l503168J-3400 Phone(503)5891252 Phone 0411330-9/55 Fat 15031/.84.0934 Fnr.150.71389-17119 Fat 04 11,111-916i Construction Materials Testing & Inspection Special Inspection FINAL SUMMARY LETTER December 14, 2009 10901252 City of Tigard 13125 SW Hall Blvd Tigard, OR 97223-8199 Attn: Building Department Re: Westgate Baptist Church—Stage Extension 10730 SW 130th Avenue—Tigard, OR Permit No.: BUP2009-00155 Dear Sir or Madam: This is to certify that in accordance with Section 1704.1.2 of the International Building Code, we have performed special inspection of the following item(s) per our inspection reports only: Reinforced Concrete Installation of Cast in Place Anchors Structural Welding All inspections and tests were performed and reported according to the requirements of Project Documents and, to the best of our knowledge, the work was in conformance with the approved plans and specifications, approved change orders and applicable workmanship provisions of the State Building Code and Standards, as well as the structural engineer's design changes, approvals and verbal instructions. Our reports pertain to the material tested/inspected only. Information contained herein is not to be reproduced, except in full, without prior authorization from this office. Under all circumstances, the information contained in this report is provided subject to all terms and conditions of CTI's General"Conditions in effect at the time this report is prepared. No party other than those to whom CTI has distributed this report shall be entitled to use or rely upon the information contained in this document. If there are any further questions regarding this matter, please do not hesitate to contact this office. Respectfully submitted, CARLSON TESTING, INC. teven W. Leach C Project Manager SWL/rb cc: "-Duttons Remodeling—Brian Dutton 503 524-4560 City of Tigard Building Division Bradford Conrad Crow Engineering Co 503 213-2018 ti