Metal-plate-connected wood trusses with semi-rigid joints were investigated by the matrix method of structural analysis. The element-stiffness matrix and fixed-end forces of an individual member with one or both ends semi-rigid were derived as modifications of the idealized cases. The case of unequal elastic connections at two ends of a...
Probability density functions (normal, lognormal, and three-parameter Weibull) were used to characterize strength data for three different types of metal-plate-connected wood truss joints (web at the bottom chord, tension splice, and heel). Modulus of elasticity (MOE) of the lumber used to fabricate the joints was also characterized. A probability-plot technique,...
The focus of this research is to develop a prototype
expert system for softwood lumber grading. The grading
rules used in the knowledge base of the system are based on
Western Lumber Grading Rules 88 published by the Western
Wood Products Association. The system includes 27 grades
in Dimension, Select/Finish,...
In order to describe long term creep behavior of structural lumber in a natural
environment, a bending test with twenty Douglas-Fir beams subjected to a constant
load was set up in an open shed in the Forest Research Laboratory at Oregon State
University. Deflections of the beams were measured along...
A commercially available, three-dimensional (3-D) finite-element (FE) analysis
program was used to model metal-plate-connected (MPC) joints in wooden trusses.
The model's features included consideration of material properties, teeth-to-grain-to-direction-
of-force orientation, and wood-to-wood contact. Non-linear spring elements,
placed on the wood surface between wood and plate, were used to represent wood-to-teeth...
The objectives of this research were to evaluate the
behavior of actual metal-plate-connected (MPC) tension-splice
and heel wood truss joints under seismic loads from the
Northridge earthquake (tension-splice joints only) and under
loads from a large artificial earthquake (1.0 g's and 0.67
g's maximum horizontal and vertical accelerations,
respectively). A...
"This publication has presented an overview of current research on MPC joints in wood trusses. The literature search was primarily of U.S. sources, with some effort to obtain literature from other parts of the world. An enormous amount of important information has been amassed by studies on testing procedures and...
Five different test methods to determine the parallel-to-grain shear
strength of Douglas-fir structural lumber were compared. Four methods
assessed the shear strength of lumber sections having a full nominal two by
four inch cross-section. These were: three-point bending, four-point bending,
five-point bending, and torsion. The fifth method was the ASTM...
