A comprehensive approach to establishing a standard test method for evaluating insulated wall panel wythe connector performance

The precast concrete industry has implemented insulated wall panels for more than 70 years in various applications worldwide; however, there has yet to be a standardized form of testing their wythe connectors, which may prevent engineers from taking advantage of the full potential of partially composite insulated wall panels. This research addresses this issue by presenting a comprehensive approach for developing a testing standard that tests braced and unbraced double shear and flexural specimens, typically implemented in the literature, to obtain the mechanical properties of partially composite wythe connectors. To devise a standard test method, 107 specimens were fabricated and tested to investigate the variables affecting the connector shear and stiffness testing results. The results showed that double shear tests provide more accurate mechanical properties than flexural test specimens. Moreover, bracing or increasing the length of the specimen up to 12 ft (36 m) showed no significant impact on the mechanical properties of the wythe con¬nectors compared with 4 ft (12 m) long specimens. The outcomes of this study will help the precast concrete community better understand the behavior of wythe connectors, test them with a certain level of confidence, and understand the foundations of the standard for testing wythe connectors.