Treesearch

Many changes have occurred in the fiber-based panel products industries during the past 50 years. During this timespan the Forest Products Laboratory has conducted a considerable amount of research on processing and product evaluation of fiber-based panel product materials. Unfortunately about 26 percent of this information was never published. completed during this timespan and briefly summarizes what was accomplished.

Computer sawmill simulation models are being used to increase lumber yield and improve management control. Although there are few managers or technical people in the sawmill industry who are not aware of the existence of these models, many do not realize the modelsa full potential. The first section of this paper describes computerized sawmill simulation models and their use for those who have an interest in the subject, but who will not necessarily be involved in their implementation. The areas of use discussed include management planning and decisionmaking, engineering, automated control...

This paper summarizes the results of load tests on an experimental highway bridge erected and put into service on the George Washington National Forest in Virginia in 1977. The bridge, made entirely of Press-Lam, a laminated veneer lumber (LVL) product, was load tested 1 month, 1 year, and 5 years after erection. The bridge continues to perform quite well and, although a slight increase in bridge flexibility was noted during this time period, the deflections were well below those calculated in the original design. Thus, laminated veneer structural members can be successfully used in...

Tests of structural use panels under different loading conditions provide basic information for establishing design stresses. This paper reports the effects of loading rate in tension and bending and of duration of load in tension on the properties of four lab-made structural flakeboards, (two of which had aligned flakes). The objective was to determine if these panels- made from larger, engineered flakes-behaved the same as commercial particleboards-made primarily from planer shavings and sawdust-that were evaluated in an earlier study. For specimens loaded to failure at different rates...

The attenuation, phase shift and depolarization of a polarized 4.81-gigahertz wave as it is transmitted through a wood specimen can provide estimates of the moisture content (MC), density, and grain angle of the specimen. Calibrations are empirical, and computations are complicated, with considerable interaction between parameters. Measured dielectric parameters, however, correlate uniquely and repeatably with MC over a range of MC at least as great as 100 percent of the dry weight of the wood. Grain angle can be deduced reliably when the specimen thickness and MC are great enough to...

This report summarizes the available data on the airborne sound transmission loss properties of wood-frame construction and evaluates the methods for predicting the airborne sound transmission loss. The first part of the report comprises a summary of sound transmission loss data for wood-frame interior walls and floor-ceiling construction. Data bases describing the sound transmission loss characteristics of other building components, such as windows and doors, are discussed. The second part of the report presents the prediction of the sound transmission loss of wood- frame construction....

This paper presents a fundamental analysis of the processing steps in the production of methanol from southern red oak (Quercus falcata Michx.) by two-stage dilute sulfuric acid hydrolysis. Data for hemicellulose and cellulose hydrolysis are correlated using models. This information is used to develop and evaluate a process design.

An analysis has been conducted on available data related to temperature and humidity effects on formaldehyde concentrations that are produced by emission from particleboard and hardwood plywood paneling. Temperature changes are described by an exponential relation while a linear relation suffices for humidity effects. Large variations exist in the results from different investigators on different boards for the exponential temperature coefficients B (–5620° to -12,480°K-1) and for the linear humidity coefficients ß (0.005% to 0.038%-1). The variations appear to be caused by experimental...

Developing countries with a timber resource that can be manufactured into finished products either for local use or export often lack the capital to build high-cost dry kilns. Many of these countries are in the tropics where solar radiation and ambient temperatures are high. The low-cost solar/wood energy lumber dry kiln described in this report was designed and tested by the Forest Products Laboratory (FPL) for such countries where solar dry kilns can be built and operated at low cost. The FPL design is for a 6,000-fbm capacity kiln having an insulated drying compartment, an external...

In some areas, harvesting mixed hardwood species may be necessary to provide enough log volume to keep a hardwood stud mill in business. Basswood and red maple should make good studs and should be suitable for combination with yellow-poplar, paper birch, or other species shown to be good performers using the Saw-Dry-Rip (SDR) process. This study evaluates basswood, red maple, and black willow for making studs using SDR. Results show that basswood and red maple have lower crook when SDR is used with either conventional or high-temperature drying. Black willow crook is lower using SDR but is...