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Madison, WI 53726-2398
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Title: Effect of multiple knots in close proximity on southern pine lumber properties

Source: fplrip-4719-034-MSU-Ross-Shmulsky

Author(s)Schmulsky, Rubin; Ross, Robert J.

Publication Year: 2017  View PDF »

Related Publications: view

Category: Research In Progress

Abstract: Knots derive from tree branches. When boards are sawn from a log, the sawblade cuts through cross sections of ingrown branches, leaving round, dark colored masses called knots (Fig. 1). Because the grain of a knot runs more or less perpendicular to the length of a board, it weakens the board, similar to how a hole at that location might weaken the board. Although multiple knots in close proximity are known to weaken lumber performance even further, lumber grading rules used to assess knot groupings in southern pine are somewhat qualitative and subjective.

Keywords: knots; modulus of elasticity; modulus of rupture; strength; stiffness; lumber

Publication Review Process: Non-Refereed (Other)

File size: 755 kb(s)

Date posted: 02/01/2017
RITS Product ID: 83998
Current FPL Scientist associated with this product
Ross, Robert J.
Supervisory Research Gen. Engineer

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