Numerical and experimental investigation of stress carrying capacity of reinforced L-shaped corner joints with corner block in wooden chair under diagonal tension

Joints are important components of any structure that can be a warranty for the strength of structures. There are different methods for reinforcement of furniture joints that are used according to position and shape of joint. One of the reinforcement methods of corner joints is using wooden corner blocks. Therefore, in this study, the effect of species types and physical situation of wooden corner block on stress carrying capacity of L-shape joint under diagonal tension was investigated numerically and experimentally. For this purpose, L-shape mortise and tenon joints of beech were constructed.. The corner blocks of beech and poplar species were applied to reinforce the joints. The physical situation for beech in three levels (without groove and with grooves 5, and 10 mm) were selected as variables. Also, a control sample (without corner block) was used for comparing. Experimental results have shown that using corner block had a significant effect on stress carrying capacity. There was no significant difference between the species. The maximum stress carrying capacity was obtained of joints that were reinforced with poplar corner block with 10 mm groove depth (30.3 MPa) and the minimum stress carrying capacity was obtained of control sample (6.06 Mpa). Results of numerical analysis have shown that maximum stress of reinforced joints with corner block are in the groove zone of joint members and corner block glue line which this stress concentration caused the failure of members in these zones.