Flexible pavements consist of multilayers, which form the pavement structures. Since the strength of the bond at interface between layers plays a significant role in improving the structural integri-ty and the performance of pavement structures, tack coat materials and methods used for their application during construction are important in providing...
The Self-indicating Instant Radiation Dosimeter (SIRAD) is credit card size, self reading, single use dosimeter produced by JP Laboratories. The SIRAD has a chemical strip that changes color based upon incident radiation. The color change is instantaneous and cumulative. The card was designed for first responders as a way for...
The Self-indicating Instant Radiation Alert Dosimeter, SIRAD™,
manufactured by JP Labs*, is a dosimeter that can be used by emergency response
persoimel. It is a user-friendly, inexpensive, and disposable radiation dosimeter. It
monitors high doses, 5-200 rads, of ionizing radiation. The card resembles the size of a
credit card and...
The merits of the photoelastic coating technique as applied to
wood were evaluated. Comparative tests were made on 12 nominal
two-by-four Douglas Fir boards. The object of these tests was to
determine the limitations of this technique, such as accuracy and
complexity of experimental procedure. Correlation of the experimental
results...
Elasticity properties of wood studs are essential inputs for
the structural analysis of wood-stud wall systems.
A theoretical procedure was developed to determine the probability
distributions for the deflection-load relations of stud samples.
The procedure is based on the finite element analysis and a Monte-
Carlo type simulation and accounts...
Biaxial strength characteristics of wood-based structural panels were evaluated by
using analytical and experimental methods. Cruciform plywood specimens were tested
under biaxial tensile-tensile, compressive-compressive loadings in a symmetrically-jointed-
arm test fixture, which was mounted on a universal testing machine. Performance
of the test fixture was also evaluated during the tests....
Woody biomass transportation costs and market values/costs are strongly correlated with the woody biomass moisture content. Properly managing moisture content can potentially lead to economic and environmental advantages in biomass energy markets. Good management requires accurate moisture content measurements. Therefore, availability of accurate, precise, reliable, and efficient tools to assess...
The Pacific Coast variety of Douglas-fir was investigated.
The samples were tested using both forced and free vibrations. Transverse
vibrations were introduced by excitations on the side of the
samples. Forced vibrations were applied from 5000 to 0 hertz by a
vibration generator, and free vibrations were initiated by a...
Publication restrictions have been removed. This report is one of a series issued in cooperation with the Army Air Forces and the Bureau of Aeronautics under the supervision of the Aeronautical Board.
Efficient use of wood in structural applications depends
upon the accuracy with which we can predict the mechanical
behavior of members under load. Most methods of lumber grading
and laminated beam design depend upon statistical and/or
empirical techniques in which averaged properties for complete
members are derived. A knowledge of...
Influence of temperature and wood moisture content on
spore germination and colonization of Douglas-fir
(Pseudotsuga jnenziesii) heartwood by Poria carbonica
basidiospores and chlamydospores was studied. Both spore
types germinated and colonized wood at moisture contents
above the fiber saturation point, but not below.
Germination and wood colonization occurred at 22°C...
The objectives of this study were to 1) develop a relatively quick staining procedure that would detect incipient decay by color differentiation under fluorescence, 2) quantitatively assess the amount of decay present with the use of an image analyzer, and 3) re/ate loss in strength at various decay levels to...
Three samples of different wood densities of Douglas-fir
(Pseudotsuga menziesii (Mirb.) Franco) were cooked by
the kraft process. The yields and the Kappa numbers were
studied to establish the rates and the energies of activation
of the pulping and delignification reactions
respectively. Wood properties did not show significant
effects on...
Current compression perpendicular-to-grain (c-perp) design values for wood members are based on mean stress using the ASTM D143 specimen. Base design value, as determined from 0.04-in deformation in the ASTM specimen, is applied to all c-perp applications. While the standard ASTM test was presumably believed to adequately reflect relevant c-perp...
Douglas-fir utility poles are routinely air seasoned before
treatment with chemical preservatives. Basidiomycetous fungi invade
these poles and may cause strength loss during air seasoning or later
if treatment temperatures are insufficient to kill the decay fungi.
The purpose of this study was to develop a rapid test to asses...