Theoretical Modeling of Bonding Characteristics and Performance of Wood Composites. Part III. Bonding Strength Between Two Wood Elements
Keywords:Wood composites, modeling, bonding strength, wood strands, compaction ratio, resin distribution
AbstractThe bonding characteristics between two wood elements (strands) were investigated using experimental and modeling approaches. Based on the mechanism of surface contact and resin coverage, the model predicted the apparent bond strength as a function of compaction ratio, resin content, and transverse tensile strength of wood. Experimental tests were conducted to determine the resin coverage and apparent bond strength of two overlapped aspen (Populus tremuloides) strands under uniform and random resin distributions. The model was validated by close agreement between the predictions and the experimental results. The results showed that the optimum compaction ratio should be between 1.25 and 1.30 for the maximum contact and apparent bond strength. Further densification would induce damage to wood and inhibit final bonding performance. The apparent bond strength was proved to be related to resin content through the direct impact of resin area coverage. The results also suggested that one could save resin consumption by reducing spot thickness and increasing spot number or coverage.
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