3003 W CASINO RD BLDG 40-21 2018-09-21

r The Boeing Company P.O.Box 3707 Seattle,WA 98124-2207 November 19, 2007 G-PN 1 A-WRL-07-114 Kirk Brooks Building Official City of Everett Engineering/Public Services 3200 Cedar Street Everett, WA 98201 Subject: Boeing Everett Building 40-21/22/32/51 Crane Replacement— Proposed use of International Existing Building Code (IEBC) Dear Mr. Brooks: The Boeing Company is currently evaluating the subject building structures for a partial replacement of the existing overhead crane system in the final assembly building complex at the Everett site. The assembly of the 747-8 Airplane model now requires an increase in the rated lifting capacity of the overhead crane system, from two hoists simultaneously lifting and moving 34 tons each to two hoists simultaneously lifting and moving 40 tons each. To accomplish this, Boeing will replace two existing bridges and three existing cabs (manned trolley/hoist units) with new equipment. The new bridge cranes will only be used in a 500-ft. northern portion of the 40-22 Building and possibly a 100-ft. southern portion of the 40-32 Building at the new 40 ton capacity. The 40 ton dual pick capacity will be electronically limited to 34 tons outside the localized area as required by roof strengthening. Additionally, existing bridges that are rated to lift and move two spaced 34 ton loads are being investigated to determine if they can support one of the new 40 ton cabs lifting and moving a 40 ton load throughout the 40-21/22/51 Buildings. The supporting structure (roof trusses and columns) must have adequate capacity to safely support the new crane equipment and rated load. Boeing has authorized Casper, Phillips &Associates (CP&A) to analyze the existing building structures and design any necessary strengthening required by the building code. The City of Everett building code requires use of the 2003 IBC for the structural evaluation and design of any strengthening required by crane replacement. In addition to a vertical load analysis, a full lateral analysis of the affected buildings would be needed to determine if there is any significant effect on the lateral force resisting system.