Racking Test Evaluation of a Single-Story Planar Unitized Curtain Wall System with Structural Glazing Tape

The objective of the study presented in this paper was to determine the racking performance of a four-side structural glazing tape curtain wall system. An EN-WALL 7250 (EN-Wall, Las Vegas, NV) unitized curtain wall system was tested using 3M VHB Structural Glazing Tape G23F (3M, St. Paul, MN). Specimens were planar and single story in configuration, features that align with most commercial unitized systems. Racking tests followed a published stepwise protocol to characterize the performance of the system for both unrestrained and restrained end-boundary conditions. Air leakage tests were also performed during to evaluate the wall system serviceability performance with respect to air leakage. Results of these tests on two full-scale specimens are presented herein. In summary, the full-scale specimens did not sustain any damage to the 3M VHB Structural Glazing Tape G23F or the glazing system. Some framing derailment occurred under very high drifts when certain boundary conditions were imposed. A complete description of the unitized system design is presented along with observations of potential serviceability issues.