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Engineer Response to Middle School Beamrizoo January 29, 2016 Mr. Chris Hansen Yelm Community Schools 104 V Street NE Yelm, WA 98597 Project: Beam - Column Conditions at Cafeteria Review, Yelm Middle School - Yelm, WA Re: Beam — Column Stability We were retained by Yelm Community Schools to review the beam - column conditions at the cafeteria noted in the summary report provided by Staaleson Engineering, P.C. for Yelm Middle School Building 100. In his report, Mr. Staaleson recommended further review of these specific conditions for potential hazards. We met with Mr. Hansen on January 26, 2016 at the site to review the condition in question and obtain as -built information on the structural framing. We verified framing at the roof, mechanical mezzanine floor and the positive connection at the glulam beam bearing is generally consistent with that indicated in the drawings for the 1984 addition. We have determined that the beam - column conditions have adequate capacity to resist the gravity loading consisting of roof weight and snow loads. The anticipated seismic performance of the beam - column connection is consistent with the condition of the building as a whole and will be generally comparable to other buildings typical of this vintage. If the building owner would like to increase the resiliency of this condition; additional bracing can be achieved with diagonal "kickers" framing to the roof or floor. This would likely be recommended if a building seismic upgrade was performed. We did observe one discrepancy with the existing drawings from the 1984 addition: • The 5 -1/8" x 12" glulam beam saddle connection to the existing concrete column (Section J -7) at the north - eastern most concrete column (see sheet S -7) appears to have only two (2) of the required four (4) expansion anchors installed. We have reviewed the demand on this anchorage with the induced eccentricity due to having only two of the four expansion anchors installed and have determined that the anchorage has adequate structural capacity in its current configuration. Please call if you have questions, Owen Bower, P.E., S.E. Structural Engineer Lund Opsahl LLC Attachment: Sheet S -7 from 1984 renovation alE ,y WASy� �'p 1201 First Avenue South, Suite 310 Seattle, Washington 98134 206- 402 -5156 www.lundopsahl.com �il . -.v. axvow -m awmoa �; iJ�R �Y ,b�,b „i I -p¢ 4, xl- -_ . TLL � � a ! . —:n; W13A c -s . t 9IX.; O 33y Z'o !- " � �� U� rv� � o o _ .� _ _ _� ,� Q- w $__ o Sao d °� o Q J o 9 by A � � ' 2°.d '� ��`� ��' o g. 3�1 �.. ��� d � TI. . - - p; z',�� "�` I �. ! _ � �- �w m�@ use � a. 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Yelm Ave. Christina Chaput Yelm, Thurston County, WA 98597 Compliance Supervisor RE: Notice of STRUCTURAL HAZARD Thurston County Resource Stewardship DATE: Tuesday, February 09, 2016 Department PAGE: 1 of 2 2000 Lakeridge Dr SW Olympia WA 98502 (360) 754 -3355 x6875 chaputc@co.thurston.wa.us Sir, 1 was a part of the EERI Team which made a Seismic safety assessment of Thurston County Schools. I was a member of Team #6 which assessed the Yelm Middle School. We made an on -site reconnaissance of the buildings at this campus to observe the conditions of the structures and the nonstructural components in order to make assessment of seismic vulnerability. Evaluation was made using methods from ASCE 41 -13 and procedures for a Tier -1 Assessment. Individual team members were assigned the task of performing the assessment of various buildings on the campus. Darrell Staaleson, P.E., S.E. performed assessment of Building # 100. During ENGINEER's reconnaissance of the structure in the Cafeteria, a deficiency was observed as follows: Beam supports at the top of pilasters are not laterally braced. In my opinion, in the absence of this lateral bracing, the beams and columns are susceptible to failure from rotation and /or lateral displacement and are potentially unstable under even moderate seismic shaking;. The failure of this connection would likely cause collapse of the roof beams into the cafeteria assembly area. The nature of the Tier -i assessment is limited in duration and scope and only allowed ENGINEER to make a cursory visual observation. There is no indication of imminent collapse. And further observations may reveal conditions that change ENGINEER's opinion. However, the construction does not appear reliable to sustain even moderate seismic shaking. The safety of the construction is questionable and should be evaluated by an Engineer. Based on my cursory visual observation of the structure, the connection observed indicates a damaged condition where performance of the structure does not meet the standards for reliable and Safe Public Use and that appears to represent a Hazard to the Life, Safety, and Welfare of the Public. ACTION REQUIRED: No person should use or occupy the cafeteria area until the hearing points of the 9 "x39" glulam roof beams are strengthened so that they are adequately and securely braced ROUTING Sent Via: To: Remarks Delivery Email Mail File Christina Chaput Building Official X Chi -is Hansen Owner's Representative X L Wroject Activ6 I5 -032 Thurston County School IVG \ECOR \Itrl unsafe construction. doc Staaleson Engineering, P.C. PROJECT: Yelm Middle School BLDG #100 - Gym, cafeteria, and administrative offices RE: Notice of STRUCTURAL HAZARD DATE: Tuesday, February 09, 2016 PAGE: 2 of 2 RECOMMENDATION. Further study should be made to determine the exact configuration of the connection, including verification of reinforcement in the pilaster, make a rigorous assessment of the structural deficiency to confirm the potential hazard, and design strengthening for the connection. As required by IBC SEC 1709.1 and WAC 196 -27 -020, ENGINEER hereby gives NOTICE to the Building Official of this apparently deficient and unsafe structural system. Please feel free to contact me if you have any further questions. SINCERELY, STAALESON ENG EWIj1G, -f.C. �, `f v FEB -92016 Darrell Staalo6n, P. E., S.E. L: \OProiect Active \15 -032 Thurston County School IVG \ECOR \ItrI unsafe construction.doc