In order to provide bridge designers with better information, International Forest Products Limited (Interfor) asked the Forest Engineering Resarach Institute of Canada (FERIC) to evaluate the bending strength and stiffness of log stringers used for constructing bridges on forest roads in coastal British Columbia. Given the lack of definitive standards for testing this material, FERIC developed a field-based test procedure and designed a test facility for destructive testing of full-size, whole-log stringers obtained from second-growth stands. Sixteen coastal Douglas-fir and twelve western hemlock logs were tested in 2003. This report describes the test procedure and methods of analysis, presents the log bending strength and stiffness results, and makes recommendations regarding future testing.
The optimum moisture content of the raw logs used in the manufacturing of oriented strand board (OSB) may be defined by a minimum requirement for fibre conversion and a maximum that will limit the cost of drying the flakes. This criterion could become the mainstay of an effective raw-log purchasing and inventory management program. However, OSB manufacturers have lacked the technology for monitoring whole-log moisture content. FERIC tested several technologies and identified time domain reflectometry (TDR) as an effective means of sampling the moisture content in a large number of logs.
Until recently, wood product manufacturers have lacked the appropriate technology to manage log inventories based on moisture content. The conventional oven-drying method cannot generate the required amount of data quickly. The Forest Engineering Research Institute of Canada (FERIC) has proven the effectiveness of time domain reflectometry (TDR) as an on-site, nondestructive method for generating moisture readings in standing or felled wood at any stage in the fibre supply chain. Industry implementation of TDR moisture profiling has potential to improve the cost and quality of manufactured wood products. This report summarizes the results of four case studies that address specific issues related to log moisture monitoring.
To assist the Alberta forest industry in making accurate surveys of decay leels in aspen stands, FERIC developed an advanced prototype of a wood hardness tester. Based on the penetration depth of a spring-loaded needle into fresh of frozen wood, the hardness tester can used to identify two levels of decayed fibre. FERIC's 1994 prototype of a wood hardness tester builds on a prototype hardness gun, or H-Gun, developed by the Northern Alberta Institute of Technology in 1990. The FERIC wood hardness tester is light-weight, durable, and easily manufactured: in field tests, data acquisition was six to eight times faster than with the H-Gun. This prototype development was funded by the Northern Forestry Centre of Forestry Canada through the Canada-Alberta Partnership Agreement in Forestry (PAIF).
An effective self-releasing choker hook should improve productivity and safety by reducing both the time to unhook in the landing and the chaser's exposure to hazard. FERIC has developed a modification to the conventional hook configuration and patented a simple, mechanical, self-releasing choker hook for cable yarding. Choker release is activated by the changing direction of pull that occurs when the operator lands the turn and begins to send the rigging back into the cutblock. Field evaluations on cable yarding operations in British Columbia, Washington State and Norway have demonstrated productivity increases exceeding 10%.
Though mechanized processing of logs at roadside is common practice elsewhere in Canada, it is a difficult activity to undertake in Coastal British Columbia because of steep slopes and large trees. In 1985, at the request of its member companies, FERIC investigated existing technology and in 1986 began to develop an attachment for a cable loader to process coastal logs. This report describes how the West coast processor was developed in cooperation with the Science Council of British Columbia, The National Research Council, Johnson Industries Limited, and members of the British Columbia Forest Industry.
Un crochet autodéclencheur efficace pour collier étrangleur devrait améliorer la productivité et la sécurité en réduisant à la fois le temps de décrochage à la jetée et l'exposition du décrocheur au danger. FERIC a mis au point une modification à la configuration traditionnelle du crochet et a fait breveter pour le téléphérage un fonctionnant mécaniquement. Le dégagement du collier étrangleur est actionné par le changement qui survient dans la direction de halage quand l'opérateur dépose la charge tout en retournant le chariot dans le bloc de coupe. Des évaluations sur le terrain d'opérations de téléphérage en Colombie-Britannique, dans l'État de Washington et en Norvège ont démontré des augmentations de productivité dépassant 10 %.
There has been no significant change in yarding-crane technology since cranes were first used on the coast in the mid-1960's. This report discussed the differential-interlock concept, introduced to small interior machines in the late 1970's, and its potential application on large coastal yarding cranes.