Testing and analytical modelling of intermediate gypsum wallboard in wood shear wall sheathing to framing connections

Abstract

Light frame wood shear walls resist lateral loads primarily through the individual nailed connections between the sheathing and framing. The most common arrangement for such shear walls is to have sheathing on one side and gypsum board on the other. In various situations it can be desirable to increase the capacity of this type of walls by fastening a layer of sheathing overtop of the drywall. This study considered the effect that an intermediate layer of gypsum has on the strength of nailed connections in shear walls, while maintaining code-defined minimum nail penetrations. Results show that intermediate gypsum placed between the sheathing and framing resulted in significantly reduced capacity and stiffness. Analytical modelling showed good correlation with experimental results. The implications of the experimental testing and modelling are that code provisions allowing the use of intermediate gypsum wallboard should not be relied upon.