Sapwood, 6.2 sapwood Heartwood, 7.0 (a) PF = phenol-formaldehyde; MDI = methylene diphenyl diisocyanate; OSB = oriented strand board; LSL = laminated strand lumber
; LVL = laminated veneer lumber.
The new generation of OSL products, and the closely related laminated strand lumber
(LSL), which uses longer strands (minimum slenderness ratio of 150; ASTM 2008a), use pressing procedures such as steam injection, preheating, or radio frequency to create a homogenous density profile more suited to framing members.
The research approach entailed the removal of 100 small specimens for mechanical testing from three types of wood products: 1.9E laminated veneer lumber, Douglas-fir 2250f-1.9E machine stress rated lumber, and 1.7E laminated strand lumber
. A select number of specimens were subject to direct impringement (flames from a propane fuel source), and were allowed to self extinguish and cool to room temperature prior to mechanical testing.
TimberStrand[R] laminated strand lumber
(LSL) is highly uniform and dense, and compared to other wood products, LSL has a high shear strength to bending strength ratio and low variability in properties.
Kenora mayor Dave Canfield is predicting an abundance of job opportunities in the area over the next three years, and points to Weyerhaeuser's new $250-million Trus Joist laminated strand lumber
plant as a major job creator.
Despite the conflicts, it is not difficult to find a home in any average American city that integrates all three building materials, using, for example, a concrete footing, steel columns, and joists made of laminated strand lumber
. So should builders separate or combine these systems?
Accordingly, a study was conducted to better define elastic constants and appropriate E:G ratios evaluated for three kinds of SCL, including laminated veneer lumber (LVL), parallel strand lumber (PSL), and laminated strand lumber
(LSL), and one type of solid-sawn lumber.
"We have received approval from the Board (of directors) to build the Trus Joist TimberStrand Laminated Strand Lumber
plant in Kenora, which is a $250-million project, and we have some other kraft pulp mill enhancement projects worth another $20 million or so," Maksymetz says.
Shear blocks in two different orientations from laminated veneer lumber, parallel strand lumber, and laminated strand lumber
(LSL) were tested and their shear strengths were compared to the shear strengths of full-sized specimens based on torsion tests from the literature.
TJM is looking into changing lumber used in laminated strand lumber
products from aspen to poplar; using OSB, instead of microlams, for the web on I-joists; and making I-joist flanges out of laminated strand lumber
instead of LVL.
Experimental materials included machine-stress-rated lumber, laminated veneer lumber (LVL), parallel strand lumber (PSL), and laminated strand lumber
(LSL) tested at three different lengths.
SCL includes materials like laminated veneer lumber (LVL), parallel strand lumber (PSL), and laminated strand lumber