The Weibull theory, an attempt to account for the variability of
measured strength in brittle materials, is described in some detail.
An important and useful modification is derived, the normalized survival
probability distribution, given by the equation
[equation]
where S is the probability that the specimen will survive the fraction...
The compressive behavior of continuous fiber composites is not as well
understood as their tensile behavior because research and industrial applications have until
recently focused on the latter. Furthermore, most theoretical and experimental studies on
the compression of composites have examined the case of unidirectional specimens with
fibers along the...
Understanding the mechanical behavior of composite materials requires extensive knowledge of fracture behavior as a crack approaches an interface between the bulk material and the reinforcement structure. Overall material toughness can be greatly influenced by the propensity of an impinging crack to propagate directly through the substrate or deflect along...
This report is one of a series issued in cooperation with Air Force-Navy-Civil Subcommittee on Aircraft Design Criteria under the supervision of the Aircraft Committee of the Munitions Board.
This report is one of a series issued in cooperation with Air Force-Navy-Civil Subcommittee on Aircraft Design Criteria under the supervision of the Aircraft Committee of the Munitions Board. Revised April 1954. Addendum added. Supplement available with revisions. No. 1842A
This report is one of a series issued in cooperation with the ANC-23 Panel on Sandwich Construction of the Departments of the Air Force, Navy, and Commerce.
This report is one of a series issued in cooperation with the Air Force-Navy-Civil Subcommittee on Aircraft Design Criteria under the supervision of the Aircraft Committee of the Munitions Board. Information reviewed and reaffirmed 1958.
This report is one of a series issued in cooperation with the Air Force-Navy-Civil Subcommittee on Aircraft Design Criteria under the supervision of the Aircraft Committee of the Munitions Board. Information reviewed and reaffirmed 1958. Original report issued April 1952.
This report is one of a series issued in cooperation with Air Force-Navy-Civil Subcommittee on Aircraft Design Criteria under the supervision of the Aircraft Committee of the Munitions Board. Information reviewed and reaffirmed May 1954 and 1962. This report was originally published in August 1949.
This report is one of a series issued in cooperation with the Army-Navy-Civil Committee on Aircraft Design Criteria under the supervision of the Aeronautical Board.
In 1987, Congress authorized a 5 year $150 million dollar research program called
the Strategic Highway Research Program (SHRP). SHRP was divided into four major
areas, including the asphalt research program. The asphalt research program was divided
into six major research contracts, one such contract, SHRP-003A was called Performance
Related...
The torsion test was evaluated as a method for determining the shear
strength of full-size structural lumber. The evaluation involved an experimental
length study, an experimental depth study, and a finite element study.
The length study consisted of fifty nominal 2x4 specimens, ten specimens
for each length, and ten American...
Torsion test was evaluated as a method to determine the shear strength
parallel to grain of full-size structural composite lumber (SCL). Experimental
results of eighty-five rectangular (44 x 140 mm²) specimens were verified by finite
element analysis. Laminated strand lumber (LSL), laminated veneer lumber
(LVL) and parallel strand lumber (PSL)...
The Asphalt Pavement Analyzer (APA) device was used to characterize the impact of various mix factors on the development of permanent deformation in dense-graded mixes given a standard compactive effort. Factors included two aggregate sizes, three VMA levels, two fines contents, three binder contents and four binder types. All specimens...
This report is one of a series issued in cooperation with the Air Force-Navy-Civil Subcommittee on aircraft design criteria under the supervision of the Aircraft Committee of the Munitions Board. Information reviewed and reaffirmed 1959. Original report issued June 1953.
This report is one of a series issued in cooperation with the ANC-17 Panel on Plastics for Aircraft of the Departments of the Air Force, Navy, and Commerce. Information reviewed and reaffirmed 1960. Original report issued October 1955.
This report is one of a series issued in cooperation with the Army-Navy-Civil Committee on Aircraft Design Criteria under the supervision of the Aeronautical Board.
Isolates of Botrytis cinerea from containerized conifer seedlings from two
nurseries in the Northern Rocky Mountains were exposed to the
dicarboximide fungicides vinclozolin and iprodione and the chlorinated
nitroaniline fungicide dicloran to evaluate occurrence and characteristics
of resistant strains. The isolates were grown on test media prepared by
incorporating the...
The low risk and sustainable implementation of nanotechnology requires understanding how nanomaterial physicochemical properties influence their toxicity. Major drivers of toxicity need to be avoided while maximizing product efficacy so nanomaterials can be produced to best serve their applications and be of low risk when intentionally or unintentionally released into...
Failure of a gusset plate that caused the I-35W Bridge collapse in Minneapolis, MN resulted in mandated rating of connections by the Federal Highway Administration (FHWA). Rating connections requires material properties as an input. The material properties are generally reported on the available detailed drawings for bridges. However, some bridges...
This report is one of a series issued in cooperation with the ANC-23 Panel on Composite Construction for Flight Vehicles of the Departments of the Air Force, Navy, and Commerce. Original report issued October 1958. Information reviewed and reaffirmed 1965.
Identifying material characteristics of composites is important in designing any
structural system. The aerospace industry relies on these material properties not only to
design a functional aircraft, but also a safe and reliable one. Since carbon fiber
composites are relatively new materials, little is known about its characteristics under
certain...
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Brian K. Bay
Identifying material characteristics of composites is important in
Testing of asphalt binders and asphalt-aggregate mixtures using dynamic
mechanical analysis is becoming popular with improvements in high-speed
computers, precision equipment, and computer software. Researchers are trying
to describe the behavior of asphalt binders and asphalt-aggregate mixtures in
terms of their time- and temperature-dependent linear viscoelastic behavior.
The objectives of...