Manufacturing condition and mechanical properties of cylindrical LVL manufactured by spiral-winding method

摘要

The mechanical properties in bending and in compression of full size cylindrically laminated veneer lumbers (C-LVL) made by spiral winding method were tested. The C-LVLs have about 300 mm outer diameter, 25 mm wall thickness, and 3600 mm length.The results obtained are as follows: 1) The modulus of elasticity (MOE) of C-LVL depends on the species of veneer raw materials, that is, MOE of C-LVL was the same as the MOE of solid lumber of the same species. 2) The number of plies affects the modulusof rupture (MOR) and the mode of failure of C-LVL. It has no effect on MOE. 3) The interlocked grain structure of C-LVL with± 10 degree in alternate layers effectively prevented decrease in MOE of C-LVL compared to that of solid lumber. 4) There waslittle effect on MOE or MOR by the addition of radial filler in C-LVL with 10 plies or more. 5) The properties in compression is about equal to those in bending. In the compression test, buckling failure was observed. These results show that C-LVL issuitable for structural uses, especially as building and construction posts.