This report compares international standards for particleboard, waferboard, OSB, MDF, hardboard as well as cement bonded wood composite panels. Property requirements are discussed and comparisons are made between countries. Formaldehyde emission regulations were surveyed in eighteen countries.
This addendum completes the presentation of the data and research findings for the project entitled "Development of a high performance OSB panel." Most of the short-term test results and preliminary long-term creep data were summarized in a previous report (Project No. 38-43-M-410) which was submitted to the Canadian Forest Service. This addendum to that report includes new data on rolling shear, revised data on shear-through-thickness, and creep data collected during a load duration of nine months, followed by a three-week creep recovery. In addition, the effects of parameters such as strand length and climatic conditions on the engineering properties are discussed for OSB, waferboard, and plywood panels. Utilization of long strands improved the majority of the properties of OSB panels produced with commercial strands. This improvement, however, was not observed for the OSB panels produced with laboratory strands.
Water soluble borates such as (Tim-Bor[tm]) are recognized for their efficacy in protecting wood and wood products form fire, insects and decay. Unfortunately they have been found to have an adverse effect on the mechanical properties of composite panels. In this study, attempts have been made to improve the adhesive bonds of the borate-treated panels and to confirm the practicality of producing borate-treated panels in a mill operation.
The long-term experimental study of waferboard behaviour under selected ramp- and dead-loads, and in constant or changing environmental conditions were completed in 1992. These test results were only available in contract reports submitted to Forestry Canada, the Structural Boards Association and the U.S. Forest Products Laboratory. The Technical Committee of the Structural Board Association suggested last year, that, in addition to developing improved test methods, a wider distribution of the available long-term creep and creep-rupture information is needed, to promote marketing of structural panel products. To improve the accuracy of the test methods used in this exploratory study, a report entitled "Problems in measuring waferboard creep and their corrections" was prepared (Appendix I) by a co-op engineering student. To provide a Canadian input into developing European long-term test methods, Forintek staff participated in preparation of a state-of-the-art review of creep in timber construction, by summarizing "Basic knowledge" (Appendix II) in co-operation with the chairman of RILEM TC 112. To disseminate the results and implications of Canadian long-term waferboard experiments internationally, a paper entitled "An overview of bending creep and creep-rupture of waferboard panels: The Forintek experience" (Appendix III) was presented at the an international Duration of Load Workshop. Finally, to provide a basic comparison of long-term behaviour of plywood, oriented strandboard and waferboard panels under identical loads and environmental conditions, a draft entitled "Creep and creep- rupture of wood-base structural panels" (Appendix IV) was prepared jointly with U.S. Forest Products Laboratory co- operators. Each of these four papers attempted to answer a series of questions concerning improvements to long-term test methods, factors affecting long-term behaviour and their possible interaction, relationships between short-term and long-term properties, and the extent of similarities or differences between the long-term behaviour of wood and wood-based panel products. Future efforts should concentrate on developing internationally standardized test methods, and analytical techniques for predicting (at least some) long-term properties from short-term tests.
Data from recent test programs for Oriented Strand Board (OSB) and waferboard were used by the Structural Board Association (SBA) in establishing levels for strength and stiffness classes. The SBA is planning to submit a proposal to CSA Technical Committee (TC) on Engineering Design in Wood for inclusion of engineering properties of Design Rated OSB. This report provides a summary of the short-term (1 to 10 minutes time-to-failure) test data to assist the members of the CSA TC on Engineering Design in Wood in their evaluation of the SBA's submission. Summary of test results is presented, and conformance of the test samples to current standards, the within-mill variability, and effects of thickness, orientation and loading mode (tension versus compression) on engineering properties are discussed. Load duration, creep, and moisture effects on strength and stiffness of OSB and waferboard are not within the scope of this report.
There are six species of poplar native to Canada's forests. One of the most abundant and widely used of the species is the aspen poplar (populus Tremuloides). Aspen has become the most desirable species for the production of oriented strandboard (OSB). Certain sections of Alberta and British Columbia have considerable stands of aspen. The aspen stands also contain varying amounts of balsam poplar (populus balsamifera) and black cottonwood (populus trichocarpa) and various hybrids of the three species. Forintek Canada Corp's Technical Advisory Committee (TAC) was asked by the B.C.Ministry of Forests to establish whether cottonwood could be a suitable furnish for the production of OSB, since it represented a sizeable potential resource in British Columbia. The poplar species are loosely identified by several names and to confirm the actual species we were referred to Mr.Bob Brash, District Manager, Dawson Creek Forest District. Mr.Brash confirmed that the species in question was in fact balsam poplar (populus balsamifera). Balsam poplar is also known as black poplar and balm poplar. An extensive literature search was conducted on the use of balsam poplar/cottonwood in the production of OSB. The literature review and a summary are reported here.
Under current ASTM D-3501 procedures, the only practical method of obtaining compressive properties of wood based panels is to glue two or more plies of the specimen together to provide a compact column cpapble of resisting buckling. It is thought, however, that this method may not provide representative compression strength and stiffness data due to load sharing.