Development of compressed wood fasteners for timber construction V. Strength properties of drift-pinned timber joints with compressed LVL plates

Moment resisting, drift pin timber joints simulating beam-column joints wer e tested in order to evaluate the moment resistance of joints with compress ed LVL plates. The joints were comprised of one or two compressed LVL plate s of 9 to 17 plies, with about 1 in 4 plies as crossband layers, and Dougla s-fir (Pseudotsuga menziesii (Mirb.) Franco) glulam. The results were as fo llows: 1) Compressed LVL had superior properties for the connecting plate, because of its high mechanical properties and very low degree of anisotropy. Both the moment resistance and the rotational stiffness of joints with T-shaped plates were lower than those of joints with hexagonal or rectangular plates . The hexagonal plate was found suitable for connecting plates. 2) Linear stress analyses were made of the moment resisting joint employing glulam and compressed LVL plates, based on the anisotropy of strength and deformation of both parts. The calculated values showed significant correla tion with the experimental values. 3) The required thickness of the compressed LVL plate was about 1/9 of the glulam width, or 17 mm. Joint properties under this condition were 1.1 to 1 .3 times as much as those of joints with a 9 -mm steel plate.