Study on the tensile strength of ready-to-assemble and fixed corner joints on medium density fiberboard

In this research measurement and comparison of tensile strength of disassemble and fixed joints made with members out of MDF were investigated. Experimental joints were made with connectors، such as hardware pieces، elite، dowel، screws and biscuits. Experimental specimens were made by following D1761 ASTM specification. Joints’ member had cross-section 20cm×18. 4cm. Each treatment had 5 specimens and totally 8 specimens were tested. Evaluation included fixed joints made with dowel (8 and 10mm in diameter) 40 and 5 mm long screws and number 10 biscuit، as well as disassemble joints made with elite، reinforced elite by dowel (8 and 10mm in diameter). Also، experiments was extended on disassemble joints made with hardwares (toothed and smooth ones) in combination with wooden dowels (8 and 10 mm). Joint members were overlaid and plain MDF، to evaluate effects of overlayment. PVA glue was applied in all joints fabrication. Results have shown that toothed hardwares functioned better than smooth ones، in corner joints. In disassemble doweled joints، those made with larger dowels، both with elite and without elite، were stronger. Larger screws، in both cases، overlayed and plain joint members، have shown higher strength.