| Nondestructive Methods for Detecting Defects in Softwood Logs, |
FEB 1996 |
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| Authors:
K. C. Schad; D. L. Schmoldt; R. J. Ross; FOREST PRODUCTS LAB MADISON WI
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 | 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. (Author). |
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| Stress Wave Technique for Determining Quality of Dimensional Lumber from Switch Ties, |
AUG 1995 |
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| Authors:
Kristin C. Schad; David E. Kretschmann; Kent A. McDonald; Robert J. Ross; David W. Green; FOREST PRODUCTS LAB MADISON WI
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| 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 ... |
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| Identifying Bacterially Infected Oak by Stress Wave Non-Destructive Evaluation |
MAR 92 |
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| Authors:
Robert J. Ross; James C. Ward; Anton TenWolde; FOREST PRODUCTS LAB MADISON WI
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| Bacterially infected wood, called wetwood, is often not visually apparent in logs or green lumber. When kiln dried, lumber containing wetwood is prone to develop costly defects. The objective of this study was to determine the effectiveness of a stress wave nondestructive evaluation (NDE) technique to detect the presence of wetwood, thereby allowing separation of bacterially infected and noninfected lumber before kiln drying. On average, this NDE technique correctly identified ... |
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| Biodegradation of Pentachlorophenol (PCP) - Treated Ammonium Boxes Using White-Rot Fungi |
30 SEP 91 |
30 pages |
| Authors:
Richard T. Lamar; FOREST PRODUCTS LAB MADISON WI
|
 | The lignin-degrading fungi Phanerochaete chroysosporium, P. sordida, Trametes hirsuta, and Ceriporiopsis subvermispora were evaluated for their ability to decrease the concentration of pentachlorophenol (PCP) and to cause dry weight loss in PCP-treated wood. Hardwood and softwood materials from PCP- treated ammunition boxes that were chipped to pass a 3.8-cm screen were used. All four fungi caused significant weight losses and decreases in the PCP concentration. The largest PCP decrease (84%) ... |
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| A Computer Program for Analysis of Fuelwood Harvesting Costs |
OCT 85 |
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| Authors:
G. B. Harpole; G. Rensi; FOREST PRODUCTS LAB MADISON WI
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| The fuelwood harvesting computer program (FHP) is written in FORTRAN 60 and designed to select a collection of harvest units and systems from among alternatives to satisfy specified energy requirements at a lowest cost per million Btu's as recovered in a boiler, or thousand pounds of H2O evaporative capacity kiln drying. Computed energy costs are used as a criterion of economic viability. Sensitivities of energy cost and fuel requirements to ... |
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| Rotational Characteristics of Pallet Joints |
AUG 85 |
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| Authors:
T. L. Wilkinson; FOREST PRODUCTS LAB MADISON WI
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| During its lifespan, a pallet must withstand its imposed load without endangering its contents or the people handling it. To determine the amount of load a pallet will withstand requires a sound engineering analysis. The moment- rotation behavior of the joints between deckboards and stringers is needed for input to such an analysis. This report describes the joint behavior as affected by (1) deckboard species, (2) stringer species, (3) type ... |
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| An Equation for One-Sided Tolerance Limits for Normal Distributions |
AUG 85 |
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| Authors:
C. L. Link; FOREST PRODUCTS LAB MADISON WI
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| An equation that does not require tables is given to determine a one- sided tolerance limit for the 100 Pth percentile of a normal distribution with confidence 1-gamma for any sample size n. This equation gives accuracy to approximately three or more significant digits when compared to tabled values. Thus it is possible to develop an automated procedure for determining tolerance limits that is not restricted to tabled values. (Author) ... |
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| Steam-Injection Pressing of Isocyanate-Bonded Aspen Flakeboards, Latitudes and Limitations |
JUL 85 |
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| Authors:
R. L. Geimer; FOREST PRODUCTS LAB MADISON WI
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| Injection of steam into a flakeboard mat during pressing significantly reduces press times. One-half-inch-thick 0.640 specific gravity (SG) isocyanate-bonded aspen flakeboard can be cured in 60 seconds by injecting 99 Btu's of steam energy per pound (Btu/lb) of board. Press time may be reduced to 40 seconds when energy consumption is increased to 177 Btu/lb of board. Two- inch-thick 0.640 SG board can be pressed in 201 seconds with 185 ... |
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| Condensation Potential in High Thermal Performance Walls. Hot, Humid Summer Climate |
JUL 85 |
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| Authors:
G. E. Sherwood; FOREST PRODUCTS LAB MADISON WI
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| To observe actual moisture patterns and the potential for condensation due to long periods of air conditioning in a hot, humid climate, a test structure was constructed near Gulfport, Mississippi, for exposure of eight types of insulated wall panels at controlled indoor conditions and typical outdoor weather conditions. Panels were instrumented with moisture sensors and tested without (Phase 1) and with (Phase 2) penetrations (electrical outlets) in the indoor surface. ... |
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| A Profile of Wood Use in Nonresidential Building Construction |
JUN 85 |
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| Authors:
H. Spelter; R. G. Anderson; FOREST PRODUCTS LAB MADISON WI
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| This report contains information on the recent status of wood-based building materials in nonresidential building construction and highlights some of the problems and opportunities wood manufacturers face. The first section covers information from the survey about characteristics of new nonresidential and nonhousekeeping building construction, such as floor area, regional distribution, and type of construction. The second provides detailed information on estimated wood use. The third presents estimates of wood use ... |
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| Rate- and Duration-of-Load Behavior of Lab-Made Structural Flakeboards |
JUN 85 |
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| Authors:
J. D. McNatt; FOREST PRODUCTS LAB MADISON WI
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| 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 ... |
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| Empirical Equations for Estimating Drying Times of Thick Rotary-Cut Veneer in Press and Jet Dryers |
MAY 85 |
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| Authors:
J. L. Tschernitz; FOREST PRODUCTS LAB MADISON WI
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| This paper describes the use of empirical equations for the analytical correlation of the drying variables-time, temperature, green thickness, and moisture content-for drying southern pine and Douglas-fir thick- cut veneers in two dryer types. The author describes a method of fitting veneer drying data to an empirical equation of a form applicable to both jet and press drying for veneers 1/8 to 1/2 inch thick across a wide range of ... |
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| FPL (Forest Products Laboratory) Design for Lumber Dry Kiln Using Solar/ Wood Energy in Tropical Latitudes |
APR 85 |
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| Authors:
J. L. Tschernitz; W. T. Simpson; FOREST PRODUCTS LAB MADISON WI
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| 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 ... |
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| Investment Limits for Small-Scale SDR (Saw-Dry-Rip) and EGAR (Edge-Glue and Rip) Sawmills |
APR 85 |
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| Authors:
G. B. Harpole; FOREST PRODUCTS LAB MADISON WI
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| A viable investment must produce an output that can be sold to generate enough revenue to cover operating costs, return capital investment, and produce sufficient profit to attract investment monies. Market prices, roundwood costs, and other operating costs essentially establish investment limits for new sawmills or converting old sawmills to new products. Using such operating factors, this paper provides algorithmic equations for estimating maximum investments for building or converting a ... |
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| Evaluation of Mixed Hardwood Studs Manufactured by the Saw-Dry-Rip (SDR) Process |
MAR 85 |
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| Authors:
R. R. Maeglin; R. S. Boone; FOREST PRODUCTS LAB MADISON WI
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| 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 ... |
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| A Microwave Method for Measuring Moisture Content, Density, and Grain Angle of Wood |
MAR 85 |
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| Authors:
W. L. James; Y. H. Yen; R. J. King; FOREST PRODUCTS LAB MADISON WI
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| 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 ... |
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| Airborne Sound Transmission Loss Characteristics of Wood-Frame Construction |
MAR 85 |
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| Authors:
F. F. Rudder Jr; FOREST PRODUCTS LAB MADISON WI
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| 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 ... |
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| Reaction of Epoxides with Wood |
DEC 84 |
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| Authors:
R. M. Rowell; W. D. Ellis; FOREST PRODUCTS LAB MADISON WI
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| This report is a summary of an 8-year research program at the Forest Products Laboratory on chemical modification of wood with epoxides. Several species of wood were tested and the reactivity of many mono and difunctional epoxides was determined. The majority of the research concentrated on the reactions of propylene and butylene oxides catalyzed with triethylamine using southern pine. Low molecular weight epoxides react with wood cell wall polymer hydroxyl ... |
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| Strength and Stiffness Analysis of Notched, Green Oak Pallet Stringers |
DEC 84 |
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| Authors:
T. D. Gerhardt; FOREST PRODUCTS LAB MADISON WI
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| Although 5.4 billion board feet of lumber was converted to 258 million pallets in 1980, design information for notched pallet stringers is limited. In this report, methodology is developed that determines stiffness and strength reductions caused by notches in pallet stringers. A finite element (FE) structural model is developed to model notched stringers. Displacement and stress predictions agree well with experimental measurements. The author derived closed form equations that approximate ... |
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| Structural Fire Design: Wood |
OCT 1984 |
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| Authors:
E. L. Schaffer; FOREST PRODUCTS LAB MADISON WI
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| Analytical procedures to predict the fire endurance of structural wood members have been developed worldwide. This research is reviewed for capability to predict the results of tests in North America and what considerations are necessary to apply the information here. Critical research needs suggested include: (1) Investigation of load levels used in reported tests, and parameters in analyses, for application to North American practice; (2) the effect of lumber grade ... |
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| The Influence of Moisture Content on the Flexural Properties of Southern Pine Dimension Lumber |
OCT 1984 |
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| Authors:
T. E. McLain; A. L. DeBonis; D. W. Green; F. J. Wilson; C. L. Link; FOREST PRODUCTS LAB MADISON WI
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| Based on the study results we conclude that: (1) In general, drying increases the flexural properties of Southern Pine dimension lumber. (2) Improvements in Moduli of Rupture (MOR) and Moduli of Elasticity (MOE) with drying are significant for Select Structural lumber at virtually all levels of the cumulative frequency distribution. The magnitude of the increase for mean MOE and fifth percentile MOR for Select Structural lumber appears to exceed that ... |
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| Marine Exposure of Preservative-Treated Small Wood Panels |
OCT 1984 |
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| Authors:
B. R. Johnson; D. I. Gutzmer; FOREST PRODUCTS LAB MADISON WI
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| Small wood panels treated with many different chemicals have been exposed to limnorian and teredine marine borers in the sea at Key West, Florida. These preservatives and treatments include creosotes with and without modification, waterborne salts, salt-creosote dual treatments, chemical modifications of wood, and modified polymers. In spite of the accelerated nature of this test, many treated panels remain free of attack after 13-1/2 years in the sea. Untreated panels ... |
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| Deflections of Uniformly Loaded Floors. A Beam-Spring Analog |
SEP 1984 |
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| Authors:
W. J. McCutcheon; FOREST PRODUCTS LAB MADISON WI
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| A new method for computing the performance of uniformly loaded wood floors is presented. The procedure presents a floor as a simple structure consisting of a beam supported by elastic springs. The method computes midspan joist deflections which are virtually identical to those obtained from a large- scale finite element program, but a fraction of the computational effort. Also, computations agree very closely with laboratory results. A simple BASIC program ... |
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| Racking Performance of Light-Frame Walls Sheathed on Two Sides |
SEP 1984 |
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| Authors:
M. Patton-Mallory; R. M. Gutkowski; L. A. Soltis; FOREST PRODUCTS LAB MADISON WI
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| Walls in light-frame construction resist in-plane shear forces, known as racking forces, by the interaction of the sheathing diaphragm and wood frame through the fasteners. Wall performance tests provide racking strength for a particular sheathing, fastener and wood frame configuration. Small-scale shear wall length (aspect ratio) on racking resistance, (2) additive nature of single- sided walls to determine racking resistance of double-sided walls, and (3) relative racking resistance of interior- ... |
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| Computer Model for Economic Study of Unbleached Kraft Paperboard Production |
AUG 1984 |
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| Authors:
P. J. Ince; FOREST PRODUCTS LAB MADISON WI
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| Unbleached kraft paperboard is produced from wood fiber in a industrial papermaking process. A highly specific and detailed model of the process is presented. The model is also presented as a working computer program. A user of the computer program will provide data on physical parameters of the process and on prices of material inputs and outputs. The program is then used to calculate material and energy requirements of the ... |
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| The Role of Water Repellents and Chemicals in Controlling Mildew on Wood Exposed Outdoors |
JUL 1984 |
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| Authors:
W. C. Feist; FOREST PRODUCTS LAB MADISON WI
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| The natural look of wood siding, and the retention of that look, has become increasingly popular over the past several years. Many new commercial formulations are being offered for use as clear natural wood finishes. A successful finish will retain color, control mold and mildew, and minimize weathering. Some of these formulations contain a chemical as a mildewcide (fungicide, preservative) and/or a water repellent, and some do not. Several chemicals ... |
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| How Some Test Variables Affect Bending, Tension, and Compression Values for Particle Panel Products |
JUL 1984 |
11 pages |
| Authors:
J. D. McNatt; M. J. Superfesky; FOREST PRODUCTS LAB MADISON WI
|
| Three different particle panel products-particleboard, waferboard, and alined flakeboard (lab-made)--were tested in bending, tension, and compression to evaluate the effects of various test conditions and specimen sizes on strength and stiffness. Standard ASTM-size bending specimens were loaded at midspan or at the quarter points. There were no substantial differences between the two loading methods in average modulus of rupture or modulus of elasticity (MOE) values obtained for any of the ... |
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| Trends in the Production and Consumption of Major Forest Products in the United States |
JUL 1984 |
|
| Authors:
D. B. McKeever; C. A. Hatfield; FOREST PRODUCTS LAB MADISON WI
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| This report presents statistical information in tables and graphs on past trends in the production, consumption, and foreign trade of forest products in the United States. It follows the flow of wood through the U.S. economy from the Nation's forests, through the primary and secondary wood-processing industries, to the final end uses. (Author) |
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| Dimension Yields from Yellow-Poplar Lumber |
JUN 1984 |
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| Authors:
R. C. Gilmore; S. J. Hanover; J. D. Danielson; FOREST PRODUCTS LAB MADISON WI
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| The available supply of yellow-poplar(Liriodendron tulipifera L.), its potential for new uses, and its continuing importance to the furniture industry have created a need to accumulate additional information about this species. As an aid to better utilization of this species, charts for determining cutting stock yields from yellow-poplar lumber are presented for each of the five top grades. Adjustment charts present the changes for specified width cuttings, also by grade. ... |
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| Trends in the Production and Consumption of Major Forest Products in the United States. Charts for Use in Classes and Meetings |
JUN 1984 |
|
| Authors:
D. B. McKeever; C. A. Hatfield; FOREST PRODUCTS LAB MADISON WI
|
| This report presents 124 charts (figs. 1-124) of statistical information on past trends in the production, consumption, and foreign trade of forest products in the United States. The intent is to provide charts for use in classes or meetings by anyone interested in communicating this information, such as teachers, industry personnel, or state and federal resource managers. The large format of the charts makes them suitable for use with opaque ... |
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| Purdue Plane Structures Analyzer II. A Computerized Wood Engineering System. 1983 Version |
MAY 1984 |
|
| Authors:
S. K. Suddarth; R. W. Wolfe; FOREST PRODUCTS LAB MADISON WI
|
| The Purdue Plane Structures Analyzer (PPSA) is a computer program developed specifically for the analysis of wood structures. It uses recognized analysis procedures, in conjunction with recommendations of the 1982 National Design Specification for Wood Construction, to determine stresses and deflections of wood trusses and frames. The program offers several options for the analysis of member capacity, depending on lateral support conditions, strength property variations, and critical load assumptions. Tabulated ... |
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| Strength of Southern Pine 2 x 4 Beam-Columns |
MAY 1984 |
|
| Authors:
J. J. Zahn; FOREST PRODUCTS LAB MADISON WI
|
| This paper presents a finite element program, Ultimate Strength of Beam-Columns (USBC), able to simulate the destructive testing of in-grade lumber under combined bending and compression. It also presents two kinds of test data on southern pine 2 x 4's: tests of short members provide an input properties distribution for USBC, and tests of full-length members in seven groups of various lengths and grades provide verification data to evaluate the ... |
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| Effect of Mechanical Stress on the Dielectric Properties of Wood |
APR 1984 |
|
| Authors:
W. L. James; FOREST PRODUCTS LAB MADISON WI
|
| The effect of mechanical stress parallel to the electric field on the polarizability (dielectric constant) and equivalent parallel conductance of wood was studied as a possible means for monitoring drying stresses. For electric and mechanical stress parallel to the grain, the effect was observable in wood that was moisture equilibrated at 65 percent relative humidity or greater, but was rather small and variable and drifted considerably with time. For stresses ... |
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| The Softwood Plywood Industry in the United States, 1965-82 |
APR 1984 |
|
| Authors:
D. B. McKeever; G. W. Meyer; FOREST PRODUCTS LAB MADISON WI
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| Predicting the Strength of Wood-Joist Floors |
APR 1984 |
|
| Authors:
D. L. Wheat; R. C. Moody; FOREST PRODUCTS LAB MADISON WI
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| This study was intended to explore the relationships between strengths at first rupture predicted by linear and nonlinear models for wood- joist floors of a given configuration but having various combinations of joist material properties. The study produced two ways of altering linear models to account for the nonlinear behavior of nails in floors loaded to failure. The strength at first joist failure of 72 floors was analyzed using linear ... |
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| Longtime Performance of Trussed Rafters with Different Connection Systems |
APR 1984 |
|
| Authors:
T. L. Wilkinson; FOREST PRODUCTS LAB MADISON WI
|
| In 1967, the Forest Products Laboratory initiated a study on the longtime performance of trussed rafters with different connection systems. The trussed rafters were loaded and exposed to sheltered outdoor conditions for 5-, 10-, and 15-year periods. After each 5-year period, one trussed rater of each connection system was evaluated in the laboratory. Strength and stiffness was compared to a control trussed rafter tested at the program's beginning. Results after ... |
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| Factors Determining Lumber Recovery in Sawmilling |
APR 1984 |
|
| Authors:
P. H. Steele; FOREST PRODUCTS LAB MADISON WI
|
| Lumber recovery in sawmilling is determined by a confusing interaction of several variables. Since no two sawmills are alike, the variables that influence lumber recovery are seldom the same from one sawmill to another. This complexity confuses even those with a wide range of knowledge and experience in sawmilling. Knowing the variables that affect lumber recovery in general can unravel the factors present in a specific mill. The purpose of ... |
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| Electric Moisture Meters for Wood. Revised |
JAN 1984 |
|
| Authors:
W. L. James; FOREST PRODUCTS LAB MADISON WI
|
| Electric moisture meters measure moisture content of wood in terms of its electric resistance or dielectric properties, which vary reasonably consistently with moisture contents under about 30 percent. Moisture meters may be either handheld or stationary. Readings of these meters are affected by such factors as species, temperature, chemical treatments, moisture distribution, operator skill, and others. Information is given here either to correct for these factors or to minimize errors ... |
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| Improved Aspen Mechanical Pulp through Coarse Grinding and Refining |
DEC 1983 |
|
| Authors:
D. C. Hedquist; J. F. Laundrie; FOREST PRODUCTS LAB MADISON WI
|
| A pilot scale study was conducted to determine the feasibility of refining coarse aspen groundwood (GW) pulp to increase the utilization of aspen and thereby lessen the demand for softwoods. The pulping rate of the grinder was nearly doubled by coarse grinding, and at comparable freenesses, the quality of the unbleached refined coarse GW pulp was equal to that of typical aspen GW pulp from the mill. Alkaline bleaching and ... |
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| Light-Frame Wall Systems: Performance and Predictability |
DEC 1983 |
|
| Authors:
D. S. Gromala; FOREST PRODUCTS LAB MADISON WI
|
| Conventional analysis methods seriously underestimate the strength and stiffness of light-frame wall systems. To better predict the strength and stiffness of these systems, a finite element based computer program, FINWALL, has been developed at Oregon State University (OSU). Previous testing at OSU during model development can now be augmented by the tests described in this paper to provide additional model verification. Test results are presented for 10 walls loaded under ... |
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| Wood Used in U.S. Manufacturing Industries, 1977 |
DEC 1983 |
|
| Authors:
D. B. McKeever; D. G. Martens; FOREST PRODUCTS LAB MADISON WI
|
| This report provides 1977 estimates of all uses of wood-lumber, logs and bolts, plywood and veneer, hardboard, insulation board, particleboard, and medium-density fiberboard-in all phases of manufacturing. Changing trends and patterns are examined. Included are the quantities of wood products used for materials handling (pallets and skids), packaging, shipping (dunnage, blocking, and bracing), and the making of jigs, models, patterns, and flasks used in the manufacturing process, as well as ... |
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| Contribution of Gypsum Wallboard to Racking Resistance of Light-Frame Walls |
DEC 1983 |
|
| Authors:
R. W. Wolfe; FOREST PRODUCTS LAB MADISON WI
|
| Gypsum wallboard is the most commonly used interior wall sheathing material. Evidence suggests that it contributes to the shear performance of light-frame walls; however, it has received little recognition as a structural material. A better understanding of the structural behavior of gypsum wallboard could contribute to more efficient light-frame construction. Thirty light-frame walls were evaluated to characterize the gypsum wallboard contribution to shear wall racing performance. Variables studied included windbracing, ... |
|
| Comparison of Wood Preservatives in Stake Tests (1983 Progress Report) |
DEC 1983 |
|
| Authors:
L. R. Gjovik; D. I. Gutzmer; FOREST PRODUCTS LAB MADISON WI
|
| This report covers test stake results primarily from southern pine sapwood 2 by 4 by 18 ;inches in size, treated by pressure and nonpressure processes, and installed by the Forest Products Laboratory and cooperators in our decay and termite exposure sites at various times since 1938 at Saucier, Miss., Madison, Wis., Bogalusa, La., Lake Charles, La., Jacksonville, Fla., and the Canal Zone, Panama. Also included in the tests at Saucier, ... |
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| Stiffness and Strength of Uniformly Loaded Floors with In-Grade Lumber |
NOV 1983 |
|
| Authors:
M. D. Vanderbilt; M. E. Criswell; J. Bodig; R. C. Moody; D. S. Gromala; FOREST PRODUCTS LAB MADISON WI
|
| To implement more efficient design techniques for wood joist floor systems, existing systems with a history of satisfactory service must be characterized. Such a procedure, known as calibration, is necessary to ensure that new design techniques and construction materials do not change the overall acceptability of wood floor systems. To characterize such performance, a structural analysis model and computer program for floors, FEAFLO, was used with data on numerous samples ... |
|
| Long-Term Load Performance of Hardboard I-Beams |
NOV 1983 |
|
| Authors:
J. D. McNatt; M. J. Superfesky; FOREST PRODUCTS LAB MADISON WI
|
| Built-up I-beams with hardboard shear webs and laminated-veneer lumber flanges exhibited satisfactory performance when subjected to constant loads for up to 5 years in interior, protected exterior, and controlled cyclic humidity environments. Creep deflection was greatest for beams in the cyclic humidity environment and least for those in the interior environment. For beams loaded at the same stress level in a given environment, deflection was greater for beams made with ... |
|
| Data for Prediction of Mechanical Properties of Aspen Flakeboards |
SEP 1983 |
|
| Authors:
Charles G. Carll; Peiyuan Wang; FOREST PRODUCTS LAB MADISON WI
|
| This research compared two methods of producing flakeboards with uniform density distribution (which could then be used to predict bending properties of flakeboards with density gradients). One of the methods was suspected of producing weak boards because it involved exertion of high pressures on cold mats. Although differences were found in mechanical properties of boards produced by the two methods the differences were not great. This suggests that exertion of ... |
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| Maximum Cutting Yields for 6/4 Ponderosa Pine Vertical Grain Lumber |
SEP 1983 |
|
| Authors:
Kent A. McDonald; Pamela J. Giese; Richard O. Woodfin; FOREST PRODUCTS LAB MADISON WI
|
| The moulding and millwork industries process nearly 1.3 billion board feet of Ponderosa Pine annually. Unfortunately, thousands of trees are harvested unnecessarily to compensate for less than optimum processing. To help improve this situation, researchers at the Forest Products Laboratory developed maximum cutting yields for 6/4 Vertical Grain Ponderosa Pine lumber in grades No. 1, No. 2, and No. 3. Yields were developed by building a representative 6/4 Vertical Grain ... |
|
| CROMAX: A Crosscut-First Computer Simulation Program to Determine Cutting Yield |
AUG 1983 |
|
| Authors:
Pamela J. Giese; Jeanne D. Danielson; FOREST PRODUCTS LAB MADISON WI
|
| CROMAX simulates crosscut-first, then rip operations as commonly practiced in furniture manufacture. This program calculates cutting yields from individual boards based on board size and defect location. Such information can be useful in predicting yield from various grades and grade mixes thereby allowing for better management decisions in the rough mill. The computer program CROMAX was written in ASCII FORTRAN on the University of Wiscosin's UNIVAC 1100/ 80 computer. The ... |
|
| Characterization of Physical and Mechanical Properties of 2 by 4 Truss Lumber |
AUG 1983 |
|
| Authors:
C. C. Gerhards; FOREST PRODUCTS LAB MADISON WI
|
| This paper summarizes data on dimensional characteristics, optimum grade, and regressions of strength on modulus of elasticity and grade class (a function of strength ratio) of lumber specimens sampled from truss fabricators in Illinois. Averages of dimensions, area, section modulus, and moment of inertia of the nominal 2- by 4-inch specimens at 12 percent moisture content were very close to those for standard dimensions (1.5 by 3.5 in.); distributions of ... |
|
| Maximum Cutting Yields for 6/4 Ponderosa Pine Shop Lumber |
AUG 1983 |
|
| Authors:
Kent A. McDonald; Pamela J. Giese; Richard O. Woodfin; FOREST PRODUCTS LAB MADISON WI
|
| The moulding and millwork industries process nearly 1.3 billion board feet of Ponderosa Pien annually. Unfortunately, thousands of trees are harvested unnecessarily to compensate for inefficient processing. To help improve this situation, researchers at the Forest Products Laboratory developed maximum cutting yields for 6/4 Shop lumber in grades No. 1 Shop, No. 2 Shop, and No. 3 Shop. Yields lumber data base and simulating sawing of the lumber by the ... |
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Reports by Corporate Author
