SOURCES SOUGHT The University of California, Ernest Orlando Lawrence Berkeley National Laboratory (LBNL), which is operated under Prime Contract DE-AC03-76SF00098 with the U.S. Department of Energy (DOE), intends to subcontract for IFB 930 - Building 6 Seismic Upgrade Project, Phase 2, 3 and 4, Construction services. Building 6 is a one-story steel framed building built in approximately 1941. It is circular in plan with a diameter of 161ft. -4 in. and a height at the perimeter of 44 feet. The dome rises to a height of 81 feet at the center of the building. It is separated from the surrounding annex building by a 7-1/2 inch joint. The structural system of Building 6 is a steel braced frame. The roof is supported by a system of arched steel roof trusses, which are supported by 24 steel columns at the perimeter of the building. A 30 ton radial bridge crane is supported by a center pivot and another 24 steel crane columns. The Building 6 lateral system is diagonal steel bracing located around the perimeter of the building. The original structure has been modified with some original braces removed and some replaced by 4ft x 3-1/2 in. double angles connected to gussets with high-strength bolts. Considerations in the selection of the seismic upgrade approach were the congested nature of Building 6 which appears to preclude the use of heavy lifting equipment to install new structural steel. The presence of sensitive laboratory equipment and the desire to minimize concrete demolition or welding are also primary considerations. The proposed seismic upgrade project includes the replacement of existing steel braces, new connections, and modifications to the radial crane central support. These are described below: All of the existing double angle lower tier braces will be replaced with new double channel braces. Then layout will generally match existing layout except that the work-point at the base will be approximately at he top of existing floor slab. In some cases, the work point will be slightly higher to permit the braces to avoid existing equipment. New connections will be provided at the ends of the replaced braces. These will have larger gussets sized to meet the required demands. The connection of the double channels to the gusset plates will be one of three methods: high-strength bolting with shop drilled holes, high-strength bolting with field drilled holes, or welding. It is anticipated one end of the double angle braces will be connected with high-strength bolting with shop drilled holes and the other with either high-strength bolting with field drilled holes to provide installation tolerance. Welding will be limited to the braced to column connections on the ground level only. At the upper tier of bracing, some existing connections will be replaced similar to the approach described above. The restraint of the crane bridge beam central support will be modified to provide additional lateral stiffness. This is anticipated to be accomplished by adding new stiffer lateral springs. The relocation, temporary work and modification of plumbing and fire protection systems will be provided where systems are affected by or would impede the structural modification work. Similar electrical relocation and modification work will be Owner-performed. The total construction cost for the phase 2, 3 and 4 work is estimated to be between $3 million and $6 million dollars. The project will occur during three four-six week shut-down periods: Phase I has already been completed - April, 2007; Phase 2 beginning on or about April 1, 2008; Phase 3 commencing on or about April 1, 2009 and Phase 4 commencing on or about April 1, 2010. Around-the-clock work will be permitted during part of the performance time. Other contractors and client labor forces will be performing work during the same timeframe. The contractor will be required to share access, use of cranes, etc. during these shut-down periods. Three lay-down areas will be provided to the contractor for storage of materials required for construction: a remote one in the Building 51 parking area, one small area adjacent to Building 6, and one designated location within the perimeter of the work area. But for a few spaces, the contractor crew will need to park in the Building 51 parking area and carpool to the Building 6 site. Firms interested in being pre-qualified to perform this work should send a REQUEST TO RECEIVE THE PREQUALIFICATION PACKAGE, including their company name, address, phone number, fax, contact person and business size (small, large, woman owned, disadvantaged, Veteran owned, hub zone, etc.), by e-mail to:
[email protected] . A prequalification package will be sent to interested firms approx. 10/25/07 and will be due back, completed, by November 12, 2007. A site visit will be made available to interested prequalified parties mid December. After review of the submitted packages, all firms that are evaluated as being prequalified will then be sent an invitation for bid (IFB) package and information about the site visit. Firms that were previously prequalified to bid on the Phase 1 scope do not need to resubmit prequalification packages. Direct any questions concerning this announcement to Rose Hoffman e-mail
[email protected].