Treesearch

This report presents information on trends in production, trade, consumption, and prices of forest product in the United States. Although national trends are dealt with for the most part, some information is given for regions, states, and Canada. The tables presented in this report are from information collected from industry trade associations and government agencies. Some of the tables show data that are derived from mathematical calculations and conversions from different units of measurement. These data are intended for use by anyone associated with wood-using industries. One major use...

Bolted connections often fail by a shear plug or by splitting beneath the bolt caused by tension perpendicular-to-grain stress as the bolt wedges its way through the wood. Preventing this type of failure enhances both the capacity and reliability of bolted connections. This research investigated the use of fiberglass reinforcement to enhance the load-carrying capacity of bolted wood connections. Matched specimens were reinforced with one, two, or three layers of bidirectional fiberglass cloth and configured to ensure a Mode I failure as defined by the yield theory in the National Design...

The objective of this paper is to illustrate how longitudinal stress wave techniques can be useful in tracking the future quality of a growing tree. Monitoring the quality of selected trees in a plantation forest could provide early input to decisions on the effectiveness of management practices, or future utilization options, for trees in a plantation. There will likely be utilization options that will include the production of structural products that use modulus of elasticity (MOE) as part of the grading criteria. Examples include machine stress rated (MSR), solid- sawn lumber and...

The conventional test method for determining the stacking life of corrugated containers at a fixed load level does not adequately predict a safe load when storage time is fixed. This study introduced multiple load levels and related the probability of time at failure to load. A statistical analysis of logarithm-of-time failure data varying with load level predicts the safe load that would yield a 5% probability of failure for any given storage time. Results were used to (a) quantify the performance of two corrugated fiberboards having significantly different components and (b) show the...

Medium-density hardboard is used extensively as siding on residential structures. One hardboard behavior that can be measured in the laboratory is thickness swell after exposure to water. This report reviews the literature on processing variables that are known to or likely to influence thickness swell. Where the literature on hardboard is sparse, research on other wood composition materials is cited, with appropriate caveats relevant to hardboard. Initially prepared as technical guidance to the U.S. Department of Housing and Urban Development, this report should be of interest to anyone...

Wood-inhabiting bacteria are associated with wood decay and may have an indirect influence on the decay process. Bacteria are able to affect wood permeability, attack wood structure, or work synergistically with other bacteria and soft-rot fungi to predispose wood to fungal attack. Bacteria that can inhabit chemically treated wood are recognized. The natural ability of certain bacterial genera to decompose creosote, mineralize pentachlorophenol, and tolerate chromated- copper-arsenate (CCA-)-treated wood is discussed with respect to their role in the biodegradation of chemically preserved...

A critical factor in the fire endurance of a wood member is its rate of charring. Most available charring rate data have been obtained using the time-temperature curves of the standard fire resistance tests (ASTM E 119 and ISO 834) to define the fire exposure. The increased use of heat release calorimeters using exposures of constant heat flux levels has broadened the available database on wood charring. This paper presents such char rate data obtained with an Ohio State University (OSU) calorimeter. Results include char depth versus time models, char rates as function of other parameters,...

This report presents information on the contribution of the extractive industries to the domestic economy at different geopolitical scales. Areas where resource production is important to gross state or regional product, employment, or income are highlighted. Output, employment, value added, and personal and total income multipliers are reported for the energy and mineral sectors.

Wood degradation and defects, such as voids and knots, affect the quality and processing time of lumber. The ability to detect internal defects in the log can save mills time and processing costs. In this study, we investigated three nondestructive evaluation techniques for detecting internal wood defects. Sound wave transmission, x-ray computed tomography, and impulse radar were used to examine white spruce and balsam fir logs. Computed tomography resulted in the highest resolution for voids, knots, and high moisture content areas, but at a very high price. Both sound wave transmission...

In the United States, timber and agriculture are two important components of the Gross Domestic Product (GDP). The purpose of this study was to quantify the volume and value of timber in the U.S. economy in 1991 and compare the value of timber with that of agriculture. Combined, timber and agriculture accounted for 6.2 percent of total GDP in 1991, and 13.2 percent of the goods and structures portion of GDP. Primary timber products production totaled 17,889 million ft.3 in 1991 and was valued at $19,370 million. Primary agricultural products were valued at $156,094 million in 1991....