Engineering Commons^™

The Creep Response Of Cohesive Soils: A Method Of Design Using Rheological Strength Parameters, David L. Allen

Kentucky Transportation Center Research Report

The creep response of four remolded soils and undisturbed soils from two landslide sites is presented. A method for obtaining the yield stress of soil from creep test data is presented and discussed. "Viscosity diagrams", showing the location of the yield stress is approximately 50 percent of peak stress, were obtained from conventional triaxial tests. There is more scatter in data from undisturbed soils than in data from remolded soils. Mohr's failure envelopes, constructed from yield stress data, give internal friction angles having values from approximately five to ten degrees. Strength data, calculated indirectly from peak relaxation modulus, are also …

Auto-Utility Trailer Combinations On Rural Highways In Kentucky, Bruce S. Siria, Robert C. Deen

Kentucky Transportation Center Research Report

An analysis of accident records indicated that auto-utility trailer (A-UT) combinations are involved in a disproportionately high number of traffic mishaps. Locations which have a history of accidents involving A-UT vehicles indicated that differential crosswinds and unanticipated driving maneuvers contribute to the driver's loss of control. A-UT combinations contributed to the fatigue loss in pavement life approximately 50 percent as much as single-unit, two-axle, six-tire trucks (per vehicle). In general, this vehicle type constituted approximately three percent of the total traffic stream. Analysis of speed distributions indicated an equivalency factor for A-UT combinations equal to that for trucks for similar …

Traffic Control For Maintenance On High-Speed Highways, William M. Seymour, Robert C. Deen, James H. Havens

Kentucky Transportation Center Research Report

Observations were first made at lane closures on interstate highways where yellow warning signs were erected routinely in conjunction with contract work. Later data provided direct comparison between new yellow and new orange signs. One sign scheme was used throughout the study. Driver obedience improved when new signs of either color were used; this finding implies that signs should always be maintained in good condition. Orange signs were slightly more effective than yellow signs in reducing traffic conflicts and merges near the traffic cones. Results of the study tend to support the adoption of orange as the standard color for …

Thermal Oxidation Of Gallium Arsenide Phosphide., Leo Edward Coerver

Electrical and Computer Engineering ETDs

This work covers the most important basic facts about the thermal oxidation of gallium arsenide phosphide. The work is confined to lightly dopes GaAs(1-x)^px material with a phosphorus mole fraction of 0.50+-0.02. All oxidations were carried out in open tubes and consequently at atm

ospheric pressure. Initial studies over a wide range of oxidation temper­atures showed that serious surface damage to the semiconductor surface occurred if the oxidation temperature was greater than 700° C. An anneal in an inert atmosphere at a temperature no greater than 700° C for at least 90 minutes was required to obtain good pinhole-free dielectrics. …

Electron Beam Evaporated Aluminum Oxide Gate Silicon Transistors., Chang-Ching Cheng

Electrical and Computer Engineering ETDs

Aluminum oxide films prepared by the electron beam evaporation of Al2O3 tablets have been studied in metal-insulator-semiconductor devices. The structure of Al2O3 films is amorphous with a density os 2.25 gm/cm3. The film conductivity is smaller than 5x10^14 (ohm-cm)^-1 and the breakdown strength is higher than 1.3x10^6 V/cm. The transport mechanisms in the film are believed to be impurity-induced flow at room temperature and Poole-Frenkel emission at higher temperatures.

The average relative dielectric constant is about 7. The interface surface states of the MIS sample are small in the middle of the forbidden band, gradually increasing toward the band edges. …

Analysis Of A High-Heat-Flux Water Heat Pipe Evaporator, Michael Einar Berger

Mechanical Engineering ETDs

An analysis was made to determine a surface which has potential use in a high-heat-flux, low-temperature-drop water heat pipe evaporator. A comprehensive survey of the literature was made to determine those surfaces which had high-heat-flux potential under evaporation. A circumferentially grooved surface was selected as the surface to be analyzed. Two groove geometries were selected for analysis, rectangular and triangular. A mathematical model of the grooves was constructed in order to predict the maximum surface heat flux capability. In addition, a model of the heat transfer within the fluted surface was proposed which postulated that conduction through the wall and …

Local And Overall Buckling Of Cold-Formed Compression Members, John T. Dewolf, George Winter, Teoman Peköz

CCFSS Library (1939 - present)

The objective of this investigation has been to develop information on the interaction between local plate buckling and overall column buckling in cold-formed compression members with a view toward possible improvement of those provisions in the American Iron and Steel Institute Specification for the Design or Cold-Formed Steel Structural Members concerned with column design. Two types of compression members were tested: two channels connected flange-to-flange to form a box section, and two channels connected back-to-back to form an I-section. For both of these shapes, the stress at which local buckling occurs and the postbuckling strength were varied by varying the …

Evaluation Of The Traffic Noise Prediction Procedure, Kenneth R. Agent, Charles V. Zegeer

Kentucky Transportation Center Research Report

Approximately 270 noise-level recordings were obtained at 39 highway sites and compared with the noise-level predictions obtained by the procedure outlined in NCHRP Report 117. The measured noise levels were computed in terms of the A-weighted L₁₀ value (level exceeded 10 percent of time) and then compared to the predicted noise levels. A significant discrepancy was found between predicted and measured noise levels; generally, the predicted values exceeded the measured values. Average error per location was 4.8 dBA; the maximum error was 13 dBA. A nomograph was devised to correct the predicted value; this nomograph involves observer-to-roadway distances, truck …

Traffic Accident Reporting In Kentucky, Donald R. Herd

Kentucky Transportation Center Research Report

This study reviews the organizational structure and processing procedures used in accident surveillance. Consideration was given to the techniques that various state governmental agencies use in their analysis of accident reports and statistics. It was concluded that Kentucky should enact uniform accident reporting legislation. A standard form should be prescribed for use by law enforcement agencies in complying with the reporting requirement. The creation of an Accident Records Unit to receive, process, and statistically analyze the reports is recommended.

Dynamics Of Interconnected Systems With Pulse Frequency Modulators, Halil Ozcan Gulcur

Dissertations

The objective of this dissertation is to study the dynamics of systems consisting of interconnections of an arbitrary number of complete-reset pulse frequency modulators (CRPFM's) and linear dynamical subsystems (in general, time-varying, lumped and/or distributed). CRPFM, which represents a generalization of several types of pulse frequency modulators (PFM's), consists of two basic components; a multi-input dynamic element, called the timing-filter (TF) and a threshold device (TD). Whenever the output of the TF reaches a given threshold value the TD generates an impulse and, at the same time, resets all the states of the TF to zero. This dissertation is devoted …

The Effect Of Variation In The Ratio Of Specific Heats With Temperature And Pressure On Horsepower Requirements Of Reciprocating Compressors, Selim Piskin

Theses

The expansion and compression of fluids is discussed in relation to the design of reciprocating compressors. As part of this thesis, the design equations for reciprocating compressors are developed for both ideal and reel gases.

The resulting design equations contain, as one of the parameters, the ratio of the specific heats. Using published componential specific heat data, a correlation was developed relating the dependence of the ratio of specific heat on temperature and pressure for the nore common gases. These correlations were developed so as to be compatible with the compressor design equation and to provide rapid evaluation of the …

Explosive Metal Forming, Braulio Antonio Tovar

Graduate Research Papers

This study will be concerned with investigating the development of equipment and instructional materials to teach a unit of explosive metal forming in a high school Industrial Arts class. The study will be specifically concerned with: (1) dies and dies blanks for explosive forming, (2) physical phenomena such as velocity, pressure forces, etc., generated in the explosion, (3) technical and laboratory activity content regarding explosion forming, and (4) to prepare a final written report.

Strain-Aging And The Bauschinger Effect In Steel, S. P. Gupta, A. A. Johnson, Shoukat P. Kodali

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.

Properties Of Cold Compressed Steel Tubes, W. Carl Anderson

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.

Shell Roofs And Grain Bins Made Of Corrugated Steel Sheets, M. N. El-Atrouzy, George Abdel-Sayed

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.

Cold-Formed Steel Framing With Gypsum Facing, John L. Lutfallah, Frederick A. Thulin Jr.

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.

Analysis Of Light Gage Steel Shear Diaphragms, Arthur H. Nilson

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.

Shear Strength Of Deep Corrugated Steel Panels, Chingmiin Chern, James L. Jorgenson

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.

Optimization Of Long Span Truss Purlins, Richard T. Douty, James O. Crooker

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.

Automated Design Of Continuous Cold Formed Beams, Ken P. Chong, David M. Harris

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.

Innovative Designs With Cold-Formed Members And Sheets, Richard L. Tomasetti

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.

Metal Decks Used To Form Hypar-Shell Panels, Mrinmay Biswas, Jerome S. B. Iffland

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.

Design Criteria For Steel Transmission Poles, Edwing H. Gaylord

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.

Connection Strength In Thin Metal Roof Structures, Robert W. Haussler, Richard F. Pabers

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.

Analysis Of Drive-In And Drive-Thru Storage Racks, A. Longinow, M. A. Salmon, R. E. Welch

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.

Effect Of Semi-Rigid Connection To Steel Column Of Cold-Formed Perforated Singly Semmetric Section, Paul Han Cheng

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.

Developments And Application Of Lightweight Steel Components In Housing, Andrew S. Zakrzewski

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.

Light Gage Steel And The Changing Building Codes, Marin P. Walsh

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.

Structural Behavior And Design Of Thick, Cold-Formed Steel Members, Wei-Wen Yu, William M. Mckinney, Victor A. S. Liu

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.

Experimental Techniques For Plate Buckling, W. Pennington Vann, John Sehested

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.