Field of Rods: Part 2. Mockup and Performance Testing of TSSA

Abstract

ABSTRACTEric Owen Moss Architects has designed a glass cylinder roof for the 8511 Warner Drive project in Culver City, CA. Curved laminated glass tubes suspended from a structural frame provide a striking structure unequalled in structural glass design. Their pursuit of discovering methods that bring projects to public prominence is evident in this design of hanging tubes. The engineering design and redundancy was presented at Engineered Transparency 2016 and this is a continuation of the mockup and validation. The project uses nearly 200 curved annealed laminated tubes (of various lengths) suspended from a structure where mechanical fastening of the glass tube by drilled holes and bolts is architecturally unappealing. The top of the tube is designed with conventional structural silicone and a “Yoke” inside the middle of the tube is attached with TSSA. The Yoke is bonded to curved steel 65 mm × 125 mm rectangular patches with TSSA. The curved fittings attached to the glass have to be machined to match the glass that has a 305 mm radius. The engineering challenge is to use the TSSA to resist the rotational stresses between the two halves of the cylinder during wind and seismic events. Mockup challenges with glass fracture due to heat capacity of large metal fittings were resolved with engineered steel fittings that were smaller in mass and dimensionally adjusted. Additional challenges include dimensional tolerances in glass and machined fittings that resulted in trapped air in the adhesive. The aesthetic trapped air issues were overcome by layering TSSA films upon each other to resolve the tolerances. A customized quality assurance process was implemented to validate performance of the cured adhesive. Results of quality assurance tests are presented. The design team is in the process of executing the design through mockup and validation for full scale production.