Nonbuilding and Special Structures
This paper will overview the digital design aspects of the New Las Vegas Stadium currently under construction. The paper will describe both the processes, successes and lessons learnt in designing and documenting a large geometrically complex project in a compressed time frame. The main components of the stadium comprise the seating bowl and roof structure. The seating bowl contains two concrete levels, a steel framed bowl structure and reinforced concrete cores as the lateral system. The roof structure comprises a diagonally braced steel perimeter vessel structure, cantilever steel trusses, a steel compression ring and a central two way cable truss. As with many modern architectural designs, the geometry contains undulating curves in both plan and elevation. The roof was set out with a reference control surface originally set in Rhino. In order to maintain absolute geometric control, the structural geometry for documentation and fabrication (Tekla) and structural analysis (SAP2000) was driven from the same parametric model within Rhino-Grasshopper by the structural engineering team. In this project, parametrics was applied for geometric consistency rather than traditional definition for design exploration.
A suite of project specific tooling was developed using the Rhino-Grasshopper interface to set out the structural members with appropriate offsets (top of steel) for BIM and centerlines for structural analysis. In addition, project agnostic tooling was developed for Revit and Tekla to enable smooth transfer of design information from analysis to documentation and also version control for quantity tracking and design changes. This included central databases to store model information and web dashboards to enable a high level view of key metrics.
On the structural engineering front, a database centric approach was taken to manage the large quantity of analysis data between different structural component teams. Specific tooling was written around the computation of steel capacities, model comparisons for incorporation of staged construction by an external party, fast parallel computation of load combinations and estimation of acceleration response under crowd excitation per the IStructE guide.
The paper will conclude by discussing particular missed opportunities in terms of workflows and design whose current knowledge will positively affect future projects.