Treesearch

Geotextiles are any textile like material used to enhance soil structural performance. Biobased geotextiles are used for short term (6 months to 10 year) applications where biodegradability is a positive attribute, such as mulching and erosion control. Fiber options for biobased geotextiles include cereal straws, coir, jute, kenaf, flax, sisal, hemp, cotton, woodfiber and others. This report documents research the USDA Forest Service is conducting using biobased geotextiles to increase tree seedling survival rates, establish vegetation, and control erosion.

Six room/comer tests of common wall linings were conducted with gypsum-lined ceiling exposed to propane burning at 100 kW for 10 min followed by 300 kW for 10 min. This test protocol is an option provided by ISO 9705. The flashover event occurred at 1,000 kW rate of heat release within several seconds of observing flames out the doorway. The time to flashover of the fire-retardant-treated polyurethane foam was 10.5 rein, which contrasts with no flashover for some melting materials exposed to propane burning at 40 and 160 kW. The time to flashover for all the wood materials tested ranged...

Quantities of paper and wood recovered annually for recycling were estimated for all principal commercial uses in the United States, based on material consumption and end-use data. Principal categories of commercial uses were identified and relative quantities were compared. Some innovative or novel commercial product developments were identified. The potential for additional recovery from municipal solid waste, construction and demolition debris, primary timber processing residues, and other sources was also identified.

Stress-laminated timber bridges were first introduced in the United States in the late 1980s. Since that time, the concept of stress-laminating has received a great deal of attention and hundreds of bridges have been built. Most of these bridges are located on rural low-volume roads. To evaluate the performance of stress-laminated bridges, the United States Department of Agriculture (USDA) Forest Service, Forest Products Laboratory, implemented a nationwide bridge monitoring program in 1988 that was subsequently expanded in 1992 to include a cooperative program with the Federal Highway...

Researchers at the Forest Products Laboratory, USDA Forest Service, have been studying nondestructive techniques for evaluating the strength of wood. This report describes the results of a pilot study on using these techniques to determine the quality of large dimensional lumber cut from switch ties. First, pulse echo and dynamic (transverse vibration) techniques were used to determine the modulus of elasticity (MOE) of 12 untreated red oak switch ties. The ties were then sawn into nominal 2 by 8 specimens, which were later resawn into nominal 2 by 4 specimens. Pulse echo and transverse...

Recent studies on the effects of chromated copper arsenate (CCA) treatment on lumber design properties have primarily evaluated the effects of such treatment at or near 12% moisture content and at failure times of 1 to 10 min. The influence of various moisture contents and faster loading rates is unknown. This report discusses the influence of moisture content and its interaction with time-to failure on the bending strength of CCA- treated (0.4 lb/ft 3 (6.4 kg/m 3 )) lumber. The factors studied were moisture contents of 10, 15, and ³23% (green lumber) and ramp-load failure times in bending...

This report describes 53 taxa of hardwoods of North America, which are organized alphabetically by genus. Descriptions include scientific name, trade name, distribution, tree characteristics, wood characteristics (general, weight, mechanical properties, drying, shrinkage, working properties, durability, preservation, toxicity and uses) and additional sources for information. Data were compiled from existing literature, mostly from research done at the U.S. Department of Agriculture, Forest Service, Forest Products Laboratory, Madison, WI.

Research results from the value-added research and demonstration program for western hardwoods are summarized in this report. The intent of the program was to enhance the economy of the Pacific Northwest by helping local communities and forest industries produce wood products more efficiently. Emphasis was given to value-added products and barriers to increased utilization. The program was coordinated by the Pacific Northwest Research Station, the Pacific Northwest Region of State and Private Forestry, and the Forest Products Laboratory.

This document summarizes accomplishments of USDA Forest Service researchers in the area of recycling. Specifically, it describes work in economic assessment, paper recycling, recycled housing and industrial applications of recycled materials, other recycling applications, and technology transfer. The literature list includes the references cited in the text and additional publications regarding Forest Service recycling research.

The development of standardized timber bridge plans and specifications is a key element in improving design and construction practices. The bridge plans presented were developed as a cooperative effort between the USDA Forest Service, Forest Products Laboratory (FPL); the University of Alabama; and the Southern Pine Council and are the first step in developing standardized designs for the southern United States where Southern Pine is the primary structural wood species group. This publication contains standardized designs and details for three timber bridge superstructure types, including...