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86 records – page 1 of 9.

2006-07 Lumber properties program

https://library.fpinnovations.ca/en/permalink/fpipub1335
Author
Lum, Conroy
Date
March 2007
Edition
37816
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Lum, Conroy
Contributor
Canadian Forest Service
National Lumber Grades Authority
Date
March 2007
Edition
37816
Material Type
Research report
Physical Description
68 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Mechanical properties
Specifications
Grading
Specification
Series Number
5439
W-2383
Location
Vancouver, British Columbia
Language
English
Abstract
The Canadian lumber industry has identified, as a high priority, the establishment of a multi-year Lumber Properties Program that pulls together a number of urgent initiatives currently underway to establish and/or maintain Canadian lumber design values. The desire is to have an overall program that emphasizes the proper development of a longer-term strategic plan and process to deal with current and future initiatives. Combining the current industry resources with Federal Government contributions through Natural Resources Canada (NRCan), the first step in the Program has been completed: to gather the various initiatives now underway and to begin the formal development of pan-Canadian policies to guide the development, implementation and on-going maintenance of such initiatives. The key activities in 2006-07 were:
Launching of the pilot phase of the on-going monitoring program, and development of a simulation model to assist in determining what sort of trends can be reliably detected and which cannot;
Completion of the in-grade testing program on Canadian Norway spruce;
Analysis of the No.2 2x4 Hem-Fir (N) monitoring study and confirmation of the appropriateness of assigned design values;
Identification of an alternative species grouping procedure for further study;
Starting of a process under the ASTM Committee on Wood to address gaps in the Grade Quality Index provisions in ASTM Practice D1990, and
Establishing a forum for engaging the US in discussions on lumber properties issues. Lumber properties issues crucial to maintaining the competitiveness of Canadian lumber continue to be the same as in previous years: tests and means to adjust for sample representativeness using the Grade Quality Index (GQI), species grouping and re-grouping procedures, and on-going lumber monitoring. As a result, discussion on a pan-Canadian strategy and supporting policies necessary to support Canadian lumber initiatives tend to focus on these three issues. The challenge is to ensure that these issues are dealt with in a way that balances both short and longer-term needs and provides a net overall benefit to the Canadian industry.
Grading - Lumber - Specifications
Lumber Strength
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Apparatus for duration of load compression tests of dimension lumber

https://library.fpinnovations.ca/en/permalink/fpipub5460
Author
Samson, M.
Olson, S.L.
Date
March 1985
Edition
37007
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Samson, M.
Olson, S.L.
Date
March 1985
Edition
37007
Material Type
Research report
Physical Description
10 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Strength load bearing
Compression
Mechanical properties
Picea
Loads
Series Number
CFS Contract 02-50-65-593
W-211
Location
Vancouver, British Columbia
Language
English
Abstract
Picea glauca - Strength
Strength - Compression - Parallel to grain
Strength - Load bearing - Influence of duration
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Behavior of composite lumber under long-term loading

https://library.fpinnovations.ca/en/permalink/fpipub1764
Author
Alexopoulos, J.
Shields, J.A.
Date
March 1982
Edition
38281
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Alexopoulos, J.
Shields, J.A.
Date
March 1982
Edition
38281
Material Type
Research report
Physical Description
24 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Testing
Composites
Structural composites
Mechanical properties
Series Number
3-55-43-306
E-943
Location
Ottawa, Ontario
Language
English
Abstract
Composite Structural Members - Testing
Structural Composites - Strength
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Bending modulus of elasticity and strength of 1.75" x 3.5" x 96" Douglas-fir microlam and spruce specimens

https://library.fpinnovations.ca/en/permalink/fpipub5495
Author
Palka, L.C.
Rovner, B.
Olson, L.
Wakeman, R.G.
Walser, D.C.
Date
March 1991
Edition
37257
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Palka, L.C.
Rovner, B.
Olson, L.
Wakeman, R.G.
Walser, D.C.
Date
March 1991
Edition
37257
Material Type
Research report
Physical Description
12 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Veneer
Mechanical properties
Laminate product
Series Number
Appendix 2 to Forestry Canada No. 35
Contract no. 1812L007
W-874
Location
Vancouver, British Columbia
Language
English
Abstract
The purpose of this small study was to examine the effect of various test methods upon the bending moduli of elasticity and to determine the bending strength of selected Douglas-fir and spruce laminated veneer lumber specimens.
Lumber, Laminated veneer - Strength
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Bending strength of Canadian softwood lumber

https://library.fpinnovations.ca/en/permalink/fpipub5525
Author
Barrett, J.D.
Hejja, A.
Date
April 1984
Edition
37432
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Barrett, J.D.
Hejja, A.
Contributor
Canada. Canadian Forest Service.
Date
April 1984
Edition
37432
Material Type
Research report
Physical Description
10 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Mechanical properties
Canada
Softwoods
Series Number
W-1365
Location
Vancouver, British Columbia
Language
English
Abstract
Lumber - Strength
Elasticity - Tests
Softwoods - Strength
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Canadian lumber properties 2007-08 activities

https://library.fpinnovations.ca/en/permalink/fpipub1369
Author
Lum, Conroy
Date
March 2008
Edition
37861
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Lum, Conroy
Contributor
Natural Resources Canada. Canadian Forest Service
National Lumber Grades Authority
Date
March 2008
Edition
37861
Material Type
Research report
Physical Description
[13 p.]
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Strength load bearing
Mechanical properties
Loads
Series Number
5893
W-2480
Location
Vancouver, British Columbia
Language
English
Abstract
This report summarizes the progress from Year 3 of the multi-year Lumber Properties project. All activities continue to conform to the guiding principles adopted by the Lumber Properties Steering Committee (LPSC) at the start of the program. This year the first steps were taken in preparing information for discussion with the new American Lumber Standard Committee (ALSC) Lumber Properties Task Group (TG). Work continues on the review of the Norway spruce testing program and the development of an on-going monitoring program. The program has enabled the wider industry group represented by the LPSC, to be involved in monitoring progress on the program and providing strategic direction. The support has also enabled the program to retain the necessary statistical support from the University of British Columbia to not only address Canadian lumber property issues, but also contribute to technical discussions at the ALS Lumber Properties TG.
Lumber - Strength
Strength - Load bearing
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Characterizing aspen veneer for LVL/plywood products. Part 2. LVL pressing strategies and strength properties|Manufacturing characteristics and strength properties of aspen LVL using stress graded veneer

https://library.fpinnovations.ca/en/permalink/fpipub1158
Author
Wang, Brad J.
Date
August 2001
Edition
37590
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Wang, Brad J.
Date
August 2001
Edition
37590
Material Type
Research report
Physical Description
41 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Veneer manufacturing
Veneer
Mechanical properties
Populus
Laminate product
Aspen
Series Number
W-1792
Location
Vancouver, British Columbia
Language
English
Abstract
In this study, aspen veneer sheets were sampled from a Forintek member mill. Their attributes and properties were measured. Using the optimum stress grading strategy, aspen veneer was segregated into 3 distinct stiffness groups (stress grades G1, G2 and G3) and conditioned to 3 different moisture levels. An experimental design for 3-level four factors comprising veneer moisture content, veneer stress grade, mat pressure and glue spread (or resin level) was adopted. Based on the experimental design, LVL panels with different combinations of four factors were pressed until the target core temperature reached 1050C to achieve full cure followed by a stepwise decompression cycle. The LVL panel final thickness, density, compression ratio and relevant strength properties were measured. After that the effect of aspen veneer moisture, stress grade, mat pressure and glue spread and their relative importance on LVL compression behavior, hot-pressing and strength properties were evaluated using a statistical analysis program. The relationship between LVL panel properties and veneer properties was examined. Finally a method to enhance LVL modulus of elasticity (MOE) to make high stiffness LVL was discussed. From this study, the following results were found: Aspen veneer is capable of making LVL products meeting 1.8 and 2.0 million psi MOE requirements. Optimum veneer stress grading and proper pressing schedule are two important keys to the manufacture of high-stiffness aspen LVL products. Further, a possibility to make high-grade aspen LVL meeting 2.2 million psi MOE exists by proper veneer densification and optimum veneer stress grading. The roles of four factors affecting LVL pressing behavior and strength properties are quite different. Glue spread and mat pressure, rather than stress grade and veneer moisture content, are two main factors affecting hot-pressing time taken for the core to reach 1050C. With incised veneer, the moisture from the glue in the glueline affects the rise of core temperature more pronouncedly than the moisture in the veneer, and is more critical to the cure of the glue. High glue spread (44 lbs/1000ft2) not only significantly increases the hot pressing time taken for the core to rise to 1050C, but overall also decreases most LVL strength properties with the pressing schedule used. High mat pressure does not necessarily result in high LVL panel compression due to the high gas pressure that occurs in the core. Veneer stress grade and veneer moisture are the two predominant factors that mostly affect LVL strength properties. LVL panels assembled with high stress grade result in increases in both flatwise and edgewise MOE and MOR properties rather than shear strength either longitudinal or through-the-thickness. Further, using high stress grade veneer can help make more efficient structural systems in terms of both stiffness-to-weight and bending strength-to-weight ratios compared to using low stress grade veneer. High veneer moisture at 6% impairs all LVL strength properties except edgewise bending MOE. LVL compression ratio can help link veneer MOE with LVL panel edgewise bending MOE. Overall, every increase of 1% in LVL compression ratio would result in 1% increase in LVL and veneer MOE ratio. With regard to aspen LVL MOE enhancement, using high veneer stress grade gains slightly less than using low veneer stress grade. On average, every increase of 1% in aspen LVL compression ratio results in 0.82%, 1.05% and 1.20% increase in aspen LVL and veneer MOE ratio assembled with stress grades G1, G2 and G3, respectively. In practice, those conversion factors for any specific veneer can be derived based on the correlation between veneer MOE and MOE of target LVL/plywood products made with proper pressing schedules, and be further used to derive requested veneer MOE for each stress grade to perform the optimum veneer stress grading. Pressing schedules show significant effect on aspen LVL compression behavior and strength properties. Using a pressing schedule with step-wise decompression cycles following the core temperature to rise to 1050C, an excessive compression of LVL in the range of 13.5% to 27.6% is generated which results in high-stiffness LVL with an average MOE of approximate 2.0 million psi for all experiments. Although this pressing schedule has slightly longer pressing time and off-target LVL thickness than current commercial LVL pressing schedules, it helps enhance the strength properties of LVL. It is recommended that further work should include the effect of different decompression cycles and mat pressure on LVL panel compression ratio and strength properties.
Populus - Veneers - Strength
Veneers - Manufacture - Tests
Lumber, Laminated veneer - Manufacture
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Compression perpendicular-to-grain strength of MSR lumber

https://library.fpinnovations.ca/en/permalink/fpipub36914
Author
Lum, Conroy
Date
March 1989
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Lum, Conroy
Date
March 1989
Material Type
Research report
Physical Description
22 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Stresses
Compression
Mechanical properties
Grading
Series Number
CFS No. 22
contract no.5410K301
W-645
Location
Vancouver, British Columbia
Language
English
Abstract
Summary included
Strength - Compression - Perpendicular to grain
Grading - Lumber - Stress, Mechanical
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Compression strength of Canadian softwood lumber

https://library.fpinnovations.ca/en/permalink/fpipub5524
Author
Barrett, J.D.
Hejja, A.
Date
April 1984
Edition
37431
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Barrett, J.D.
Hejja, A.
Contributor
Canada. Canadian Forest Service.
Date
April 1984
Edition
37431
Material Type
Research report
Physical Description
12 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Compression
Mechanical properties
Canada
Softwoods
Series Number
W-1364
Location
Vancouver, British Columbia
Language
English
Abstract
Strength - Compression
Lumber - Strength
Softwoods - Strength
Documents
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Conformance testing of visually graded lumber : technical and statistical options

https://library.fpinnovations.ca/en/permalink/fpipub37407
Author
Palka, L.C.
Cook, Jean A.
Date
March 1988
Material Type
Research report
Field
Wood Manufacturing & Digitalization
Author
Palka, L.C.
Cook, Jean A.
Date
March 1988
Material Type
Research report
Physical Description
18 p.
Sector
Wood Products
Field
Wood Manufacturing & Digitalization
Research Area
Advanced Wood Manufacturing
Subject
Wood quality
Wood
Testing
Mechanical properties
Quality control
Qualitative analysis
Grading
Series Number
W-1305
Location
Vancouver, British Columbia
Language
English
Abstract
Conformance testing and grade verification are technically and economically complex problems. In response to an industrial request, two alternative approaches helpful for maintaining or increasing the market share of dimension lumber in residential or industrial/commercial structures have been considered. Two options were suggested for conformance sampling of commercially important lumber grades, sizes and species. One, based on a single large sample, that would allow immediate up-dating of strength properties, if needed. The other, based on a small initial sample, followed by a larger second sample, if needed. Appropriate decision rules were developed, and it was recommended that sampling and strength testing procedures for conformance evaluations be identical to those used for in-grade testing of lumber. Development and calibration of an economic model for assessing the costs of non-conformance was also recommended. A synthesis of results from the proposed initial conformance testing based on two-stage sequential sampling and from the economic analyses is needed for rational recommendations concerning near-optimum procedures of future conformance testing of visually graded dimension lumber. Specific actions should follow discussions with, and recommendations or requests from, representatives of the lumber industry.
Grading - Lumber
Strength - Tests
Wood quality - Exterior indications
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86 records – page 1 of 9.