Hollywood Casino Jamul Tree House Sequence, HD BIM, and PBEE
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By Gregory P. Luth, Ph.D., S.E. and John D. Osteraas, Ph.D., P.E.
ollywood Casino Jamul (HC Jamul) is a three-story entertainment facility, located in Jamul, California, with approximately 200,000 square feet of gaming, restaurants, and lounges atop an eight-story, belowgrade, 1,800-space parking garage. The casino structure’s innovative steel lateral force resisting system utilizes rocking braced frames and Krawinkler fuses integrated into Vierendeel trusses to produce a performance-based seismic design. This keeps the integrity of the perimeter cantilevered gravity system protected while the lateral system is repairable after a major seismic event. The parking garage is a post-tensioned concrete slab system built using an unconventional construction sequence. The casino steel structure construction was prioritized ahead of the garage structure underneath it, to compress the overall construction duration and accelerate the completion of the design-intensive casino interior. A single High Definition Building Information Model (HD BIM), developed in Tekla Structures, was used from conceptual design to construction documents, and finally to shop drawings.
Construction Sequence Structural Concept The concept was first to erect the steel casino structure, supporting it on concrete stair and elevator cores and 90-foot tall steel “stilts” that would eventually become encased in the final concrete garage columns. The final columns would be founded on conventional spread footings bearing on rock. During construction, a temporary lateral system supported the casino and provided anchorage for tension ties that braced the columns against buckling. Casino elevators and escalators would be installed with the steel. MEP, roofing, and exterior closures would be completed and theming underway when there were still months to go on the construction of the seven 550-foot by 220-foot, below grade post-tensioned concrete slabs. STRUCTURE magazine
Contractor Selection The sequencing was established to build the casino structure first. Then, the eight-story parking garage would be brought up while the intensive build out of the architectural theming, finishes, and MEP systems on the inside of the casino were put in place. A set of schematic design documents based on this concept was issued in October of 2013 and used to solicit proposals from three general contractors. The ability of the contractors to collaborate with the design team in fleshing out the details of the final design, based on cost and schedule evaluations, was paramount in the selection process. A general contractor team composed of Rudolph Libbe, an Ohiobased contractor who had previously worked with this owner and had participated in a previous HD BIM project with the design team, and C. W. Driver, a Southern California general contractor familiar with the local sub-contractor market, both embraced the concept and brought their own ideas to the interview. They were selected to team with the Jamul Indian Tribe, Penn National Gaming, and the rest of the design team to deliver the project. The contractor estimated that the proposed sequence had potential to save seven months on the schedule. With coordination and input from the general contractor, all temporary conditions from the start of construction to completion were included in the structural design.
Excavation and Retention System The excavation varied from 90 feet deep on one end to 30 feet deep on the other. The material consisted of weathered granite bedrock that ranged with depth from soft to very hard. A soil nail wall, designed by an independent engineering firm, provided permanent support for the excavation and was eventually tied to the permanent structure so that the two worked together. Excavation commenced in early 2014 with the anticipation that the bulkhead walls would take at least one
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November 2017
