Composite effects of shear connectors used for lightweight-foamed-concrete sandwich wall panels

In an effort to enhance energy efficiency of building envelopes, a new type of sandwich wall panels (SWPs) consisting of a pair of lightweight foamed concrete (LFC) panels and an insulation layer made of mineral hydrated foamed material (MHFM) was developed for this study. The structural behavior of a SWP depends on the stiffness and strength of an individual LFC panel and their composite action that is developed by shear connectors penetrating the insulation layer. With recognition that the degree of composite action for a SWP is dependent on the number of shear connectors and presence of adhesive bonds applied to the surface of each LFC panel, they were selected as test parameters. A total of 7 SWP specimens was prepared for the experimental validation on their degree of composite action. Test results show that the load-carrying and deformation capacities of SWPs are enhanced with an increase in the number of shear connectors, and at least 10 shear connectors are required for full-composite SWPs. Unlike shear connectors, the adhesive bonds selected as one of the test parameters only weakly contribute to the degree of composite action for SWPs.