Prediction of screw withdrawal resistance for plywood laminated panels and sandwich panels

Sandwich panels are favorable materials for structural or non-structural components due to durability, lightness, and longevity in service life. This study aimed to predict screw withdrawal resistance of the plywood laminated medium-density fiberboard and particleboard, and sandwich panels. In predicting the screw withdrawal resistance, withdrawal load capacity, density, and withdrawal stiffness of the materials in each layer, screw penetration depth, and screw diameter were considered. Moreover, the screw withdrawal strength of the panels was examined. Screw withdrawal tests of panels were conducted according to TS EN 13446 standard. The test results showed a proportional correlation between the density and screw withdrawal strength of the panels. The highest screw withdrawal strength was obtained for sandwich panels made of plywood and medium-density fiberboard (12.51 MPa). Furthermore, the difference between experimental and predicted screw withdrawal resistance changed from 0.20% to 24.86%. Besides, there was no statistically significant difference between the screw withdrawal strength of the top and bottom face-laminated panels. The test results showed that both face laminated panels (sandwich panels) had higher screw withdrawal strength, density, and experimental and predicted screw withdrawal resistance compared to one face laminated panels.