What is the design process used for the SpeedCore system? 

The design process published in the Pankow Foundation "Design Procedure" indicates a prescriptive approach using published material strengths. Pankow Foundation, who has been working with the developers of this system since 2006, has published a "Design Procedure for Dual-Plate Composite Shear Walls" and it is available for free download now.

AISC will be publishing a Design Guide (expected to be published in 2023) based on the research currently underway. The goals of the research include, but are not limited, to publishing a prescriptive method for SpeedCore design that takes advantage of composite action between the concrete and the steel.  

For those interested in learning more about other design methods, AISC has recently published Design Guide 32: Design of Modular Steel-Plate Composite Walls for Safety-Related Nuclear Facilities. This design guide details an elastic finite element approach for the specific application of nuclear facilities, where walls tend to differ geometrically from common buildings.

Who is responsible for designing the plate for the various loading conditions?

The final in-place condition will always be the responsibility of the design professional. The design responsibility of the phased loading of the module as a whole, the plate, and the associated connections should be evaluated and discussed directly with the contractors involved. Most importantly, the conclusion of responsibility should be delineated in the final contract. Due to the special nature of the system, there should be open communication about design responsibility to ensure a successful project.

What about the Rainier Square Tower geometry requires outriggers and belt trusses for lateral system reinforcement?

Real-World Application | Rainier Square Tower

The core is nominally 40' wide by 93' long.  For an 850 foot tall building, this results in a core to building height aspect ratio of approximately 21:1 and 9:1 respectively. The ratio of 21:1 is far too slender for a building of this height and lateral demands. In order to supplement the core, the outriggers engage columns on the perimeter of the floor plate thus greatly increasing the 'building stance' resisting the lateral demands and lowering the lateral system to building height ratio to approximately 8:1.

What modeling capabilities were utilized in the documentation phase of Rainier Square Tower?

A modeling software package, such as Autodesk Revit, is effective in documenting a SpeedCore project.

Real-World Application | Rainier Square Tower

Autodesk Revit was used for Rainier Square.

What is the expected Response Modification Coefficient, R, for the SpeedCore system?

A FEMA P695 study (a recommended methodology for reliably quantifying building system performance and response parameters for use in seismic design)  is underway which is expected to provide more guidance, but is aiming to justify an R = 8 for this system which is a higher R factor than any other shear wall system of any material.

Real-World Application | Rainier Square Tower

Though the system is expected to test at R = 8, R = 6.5 was used in the seismic analysis in Rainier Square.  Though a seismic analysis was necessary, the building is governed by wind loading due to its rectangular floor plate. R = 6.5 is in accordance with ASCE 7-10 Table 12.2-1 for a Building Frame System: Steel and Composite Plate Shear Wall SFRS.

How was this system approved, was it through use of the 2010 Seismic Provisions or the 2016 Seismic Provisions?

Real-World Application | Rainier Square Tower

The jurisdictional approval was tied to a rigorous peer-review process along with the application of a performance-based seismic design methodology. Both the 2010 Provisions as well as the 2016 Provisions (draft Provisions at the time of the design) were references to the design basis but supplemented to existing and ongoing research and testing.