Investigating the reinforcement of parallel chip lumber (PSL) obtained from reed waste and laminated veneer lumber (LVL) made of spruce with fiber reinforced polymer (FRP)

This study was conducted with the aim of investigating parallel strand lumber (PSL) made from reed waste and laminated veneer lumber (LVL) obtained from poplar wood that reinforced with glass fiber reinforced polymer (FRP) and epoxy resin.

The independent variable was LVL and PSL with FRP and their comparison control sample without FRP. The mechanical properties of the manufactured boards including bending strength (MOR) and modulus of elasticity (MOE) in the width and edge of the test sample, shear strength, compression strength parallel to the grain, internal bonding and Screw Withdrawal Strengths were investigated as dependent variables. The obtained results were analyzed in the form of completely randomized design by SPSS software.

Results showed that of all of the studied mechanical properties, the use of FRP strengthened the PSL and LVL panels. For LVL, the effect of strengthening the samples with FRP was significant at the level of 1% and also for the modulus of rupture of the width and edge samples showed an increase of 93% and 59%, respectively. The value of MOE during reinforcement with FRP showed an increase of 89.6 and 132% for the width and length of the PSL samples, respectively. For LVL, the MOE value of the width and edge of the samples increased by 54 and 95.5% with reinforcement. Reinforced PSL samples have improved their shear strength by 31%, while this value is only 2.5% for LVL. in the internal bonding test, strengthening with FRP improved the internal bonding strength of the samples by 92%. Screw Withdrawal Strengths improved by 27% due to the strengthening of the test samples with FRP.

According to the obtained results, it can be stated that the use of glass fibers and epoxy resin has a significant positive effect on the mechanical resistance of PSL made of reed and LVL and it is possible to use low quality raw materials such as reed and waste poplar wood layers.