Adhesive Through-Reinforcement Improves the Fracture Toughness of a Laminated Birch Wood Composite

Table 1

Effects of different levels of adhesive through-reinforcement on the fracture toughness and mode I opening displacement of laminated birch wood specimens bonded with an unmodified polyurethane adhesive.

No. of reinforcements	Density of reinforcements (N/cm^2)	Fracture toughness (J/m^2)	Displacement (mm)
0 (control)	0	225	41
6	0.36	287	40
12	0.72	287	47
18	1.08	327	48
24	1.43	412	56
39	2.33	542	66
51	3.04	340	57
66	3.94	353	52