Engineering Commons^™

Diffusion In Wide Grain Boundaries, J. Mimkes, Manfred Wuttig

Materials Science and Engineering Faculty Research & Creative Works

The rigorous solution of the grain-boundary diffusion problem has been approximated by a series expansion method. The calculations show that higher-order terms may be neglected in the bulk adjacent to the grain boundary. Thus, in this region Whipple's and Suzuoka's solutions represent a close approximation to the problem. Inside the grain boundary, however, higher-order approximations have to be taken into account. These approximations gain importance in the case of wide grain boundaries. The solutions obtained for an instantaneous source have been fitted to available grain-boundary diffusion data of Ni2+ in MgO at 1200°C. Numerical calculations give for the bulk diffusion …

Relationship Between Soil Support Value And Kentucky Cbr, Tommy C. Hopkins

Kentucky Transportation Center Research Report

Three slightly different correlations between Kentucky CBR's and the AASHO Road Test soil support values were developed. The first relationship was made by assuming a logarithmic scale between Kentucky CBR's of 5.2 and 100, which corresponded to values on the soil support scale of 3 and 10, respectively. The Kentucky CBR of 5.2 was determined by performing tests on the AASHO road subgrade soils. For practical purposes, the AASHO Road Test crushed stone base material was assumed to be a "100 percent CBR material" (this assumption was based on CBR data previously reported by Shook and Fang). The second correlation …

Statistical Quality Control Of Highway Construction And Materials, J. B. Venable

Kentucky Transportation Center Research Report

The objective of this report is to review existing local practices used in establishing and enforcing highway specifications and construction processes and to compare these practices. With procedures based on statistical quality control concepts. In order that statistical quality control concepts may be properly used where applicable, the first part of this report considers the general theory underlying the use of statistical control methods and the development of different types. Of acceptance plans which may be used in the highway construction industry. The second portion of the report is concerned with analyzing and comparing Kentucky's current specification requirements with typical …

Continuously Reinforced Concrete Pavement, James H. Havens

Kentucky Transportation Center Research Report

A sampling-type crack survey was made in July 1969; 200 feet in each 1000 feet were sampled. The average interval between cracks was 5.78 feet. Paving was completed in late 1968. The average crack interval in July 1970 was 4.14 feet. The 1970 survey was also a sampling type.

It is apparent that cracking approached maturity or equilibrium during the first year. Apparently, too, most of the cracking occurred during the first few weeks after construction – which suggests curing shrinkage as a contributory cause. A discussion of the significance of time and temperature will follow the presentation of other …

Evaluation Of Cored Specimens From Timber Caisson Beneath Pier No. 2 Of The Us 25 Bridge Over The Ohio River Between Covington And Cincinnati, James H. Havens, Assaf S. Rahal

Kentucky Transportation Center Research Report

Pier No. 2 of the former C&O Bridge at Covington is off-shore from the Kentucky side of the Ohio River. It was built in 1887. In 1927, this pier was extended downstream to support a new railroad bridge. The other three piers remained independent. The original structure was then converted to highway use and was purchased by the Commonwealth of Kentucky in 1937. In 1968, an engineering analysis of the superstructure indicated critical deficiencies in terms of "safety factors", and the bridge was closed to all traffic. Subsequently, various plans for reconstruction came under consideration. Of greatest significance here is …

Thermal Expansion Of Tungsten At Low Temperatures, Jayant S. Shah, Martin E. Straumanis

Materials Science and Engineering Faculty Research & Creative Works

No abstract provided.

Rotating Cylinder Apparatus For Rarefied Gas Flow Studies, Darryl J. Alofs, George S. Springer

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A Rotating Cylinder Type Apparatus is Described, Suitable for Determining Drag in Cylindrical Couette Flow of Rarefied Gases, and for Evaluating Tangential Momentum Accommodation Coefficients at Gas-Solid Boundaries. the Apparatus is Equipped with a Damping Device using Diffusion Pump Oil for Eliminating Undesirable Oscillations in the System. Tangential Momentum Accommodation Coefficients of Argon on Aluminum Were Determined with an Accuracy of ±2.5%. the Results Obtained Indicate that the Apparatus May Be Used over a Wide Pressure Range, Corresponding to Free Molecule and Continuum Flow Conditions. © 1970 the American Institute of Physics.

Instrumentation And Development Of Techniques To Measure And Evaluate Meteorological Parameters Important To Hydrology, Duane G. Chadwick

Reports

Hydro-meteorological instrumentation concepts are discussed. The necessity for an economic and reliable telemetering system is recognized and ways are shown how to achieve this objective. Particular discussion is given on total-precipitation and water-content-of-snow sensing. A method is also presented showing how to make isohyetal plots of telemetered precipitation information on an x-y plotter by use of a resistance paper method in conjunction with an analog computer.

Phase Equilibria And Thermodynamic Studies In The System Cao-Feo-Fe2o3-Sio2, M. Timucin, Arthur E. Morris

Materials Science and Engineering Faculty Research & Creative Works

Phase equilibria and thermodynamic properties of the system CaO-FeO-Fe₂O₃-SiO₂ were studied at 1450° and 1550°C, over a range of pO₂ from 1 to about 10-11 atm. Isothermal phase diagrams and activity-composition diagrams were constructed for 0, 5, 10, 20, and 30 wt pct SiO₂ sections. The data are applicable to further understanding the behavior of simple BOF steelmaking slags. © 1970 The Minerals, Metals & Materials Society - ASM International - The Materials Information Society.

Raman Scattering From Localized Vibrational Modes In Gap, D. T. Hon, W. L. Faust, W. G. Spitzer, P. F. Williams

P. F. (Paul Frazer) Williams Publications

High-frequency localized vibrational modes of impurities in a III-V compound have been observed by Raman scattering. Three lines from the GaP samples closely correspond to some loccal modes previously reported in infrared studies, and depolarization measurements tend to confirm their proposed assignments. We describe several attractive features of this method for the study of semiconductor impurities.

A Role For Educational Institutions In Housing Development, Paul J. Grogan

International Symposia on Low Cost Housing Problems

No abstract provided.

Low Cost Housing (How To Avoid The “Problem” In Three Words Or Less), Carl P. D. Sharpe

International Symposia on Low Cost Housing Problems

No abstract provided.

Modular Housing, Herbert Behrend

International Symposia on Low Cost Housing Problems

No abstract provided.

Development By Means Of Semi-Permanent Building: A New, Practical Approach In Housing And City-Planning, B. E. Friedjung

International Symposia on Low Cost Housing Problems

No abstract provided.

"The Buckle-Shell", V. J. Meyers, V. C. Matzen

International Symposia on Low Cost Housing Problems

No abstract provided.

Low Cost Housing In The Perspective Of Metropolitan Calcutta’S Urban Renewal, S. Ghosh Dastidar

International Symposia on Low Cost Housing Problems

No abstract provided.

A Building System Using Precast Concrete Sandwich Panels From Footing To Roof, E. L. Hansen, J. O. Curtis

International Symposia on Low Cost Housing Problems

No abstract provided.

A Hyper-Roof Concept For Low-Cost Housing, John V. Huddleston

International Symposia on Low Cost Housing Problems

No abstract provided.

An Experiment In Low Cost Housing In Stillwater, Oklahoma, William H. J. Cleverly, Phillip G. Manke

International Symposia on Low Cost Housing Problems

No abstract provided.

The Mobile Home Is Low-Cost Housing -- Or Is It?, Walter L. Meyer

International Symposia on Low Cost Housing Problems

No abstract provided.

Cultural Bases Of Preference For The Visual Appearance Of Residential Environments, Peter G. Flachsbart, George L. Peterson

International Symposia on Low Cost Housing Problems

No abstract provided.

A Self-Help Process For Low Cost Housing Construction In Pittsburgh, Dennis H. Parr

International Symposia on Low Cost Housing Problems

No abstract provided.

Low Cost Housing Projects In India, A. R. Santhakumar

International Symposia on Low Cost Housing Problems

No abstract provided.

Low Income System Key Assembly, Darin V. Liska

International Symposia on Low Cost Housing Problems

No abstract provided.

Concrete Sandwich Panels For Low Cost Housing Construction, Robert W. Ellis Jr., Steven D. Cummings

International Symposia on Low Cost Housing Problems

No abstract provided.

Effect Of The Supply Of Low Cost Housing On In-Migration Of The Unskilled, Daniel L. Babcock

International Symposia on Low Cost Housing Problems

No abstract provided.

Preconditions For And Benefits Of The Development Of Low Cost Housing Technology, E. L. Keating, E. S. Miller

International Symposia on Low Cost Housing Problems

No abstract provided.

A U.S. Building System: An Experience And Lessons To Be Learned, Sepp Firnkas

International Symposia on Low Cost Housing Problems

No abstract provided.

Impact Of Planned Policy And Sociological Factors On Low Cost Housing Programmes, D. R. Sikka

International Symposia on Low Cost Housing Problems

No abstract provided.

Construction Methods For Low Cost Housing, A. M. Mahajan

International Symposia on Low Cost Housing Problems

No abstract provided.