Investigation of shear strength of joints made of medium-density fiberboard and particleboard with screw connectors

In this research, the shear strength of joints made of medium-density fiberboard (MDF) and particleboard with screwshas been evaluated. Therefore, T-shaped joints were made from two pieces with a dimensions of 7.5 x 15 cm by one screw as a fastener. The screw was selected as a variable in three levels of diameter: 4.2, 5 (panel screw), and 6 mm (Allen socket head cap screw). The Joints, were tested under shear load in two directions, parallel and perpendicular to the edge of the main member. The loading rate was 5 mm/min. The results have shown that MDF and particleboard have similar performance against shear loading. The screw diameter had a significant effect on the strength of joints in shear loading. Joints made with MDF and particleboard have a better performance against shear load when the load was perpendicular to the edge of the main member. Also, the results have shown that the joints made with 6 mm diameter screws in both MDF and particleboard show more resistance against shear loading. This increase was more noticeable in the case of loading perpendicular to the edge of the main member. The mode of failure results showed that the loading type affected in the failure of specimens. In parallel loading to edge loading internal bounding has been effective, while in perpendicular to edge loading in addition to the internal bounding, surface density has also been effective.