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Session 6: Discussion And Replies, Multiple Authors Apr 1981

Session 6: Discussion And Replies, Multiple Authors

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

No abstract provided.


On The Use Of Nonlinear Soil Models, Albert T. F. Chen Apr 1981

On The Use Of Nonlinear Soil Models, Albert T. F. Chen

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

The basic definitions of, and the differences between, currently available soil models are reviewed. These models are applied to site response analyses where two depths and two levels of base input motion are considered. Computational results are presented and compared with regard to the effects of using different soil models on computed site response. Other implications resulting from the choice of soil model for seismic response analysis are also discussed.


Source Mechanism And Seismic Effect Of Tangshan Earthquake, Hong-Qi Fang, Xin-Kwan Miao, Shu-Dong Zhao Apr 1981

Source Mechanism And Seismic Effect Of Tangshan Earthquake, Hong-Qi Fang, Xin-Kwan Miao, Shu-Dong Zhao

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

By analyzing the seismic mechanism of the Tangshan earthquake and its pattern of movement through the study of ground deformation and ground strain of the Tangshan earthquake area it is clear that the breeding and occurrence of this event are controlled by a long-term intense active fault zone. By the ground deformation, displacement, tectonic features and seismic effects after the event, this causative fault is known to be composed of a group of NNE trending right turn strike-slip faults and thus we call it the Tangshan active fault zone.


Geomechanics Of Reservoir Induced Seismicity, Thomas Vladut Apr 1981

Geomechanics Of Reservoir Induced Seismicity, Thomas Vladut

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Although induced seismicity associated with the impounding of reservoirs is a relatively rare phenomenon, it should nevertheless be taken into account, particularly in the design of dams located in aseismic zones. The operation of dams is not significantly affected by induced activities: the main concern arises in situations where unexpected events might affect the behavior of the construction due to soil liquefaction or might affect slope stability. This paper reviews the principal elements which are considered to affect the occurrence of the phenomenon: the weight of the water storage, and the development of pore pressure under the storage. Both elements …


Discussions, Dinesh C. Gupta, G. L. Hempen Apr 1981

Discussions, Dinesh C. Gupta, G. L. Hempen

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

No abstract provided.


Deposition Of Suspensions In A Vertical Converging Tube, Kam-Ho Chan Jan 1981

Deposition Of Suspensions In A Vertical Converging Tube, Kam-Ho Chan

Theses

The deposition of suspensions in a vertical converging tube with significant gravity effects Was investigated theoretically with control volume - finite difference approach. The fluid was assumed to be incompressible and laminar. The particle density was assumed to be uniform at the inlet of the. tube. The velocity profiles for the fluid considered were (a) Uniform profile, (b) Parabolic profile. The angles of convergence studied were 0°, 5° and 7°. Effects of velocity ratio δ*(=terminal velocity/mean flow velocity) on the rate of deposition were investigated for δ*=0,1,10.

It was found that deposition increases with increasing angle …


A Mini-Computer Based General Purpose Interactive Computer Graphics Software System, Victor M. Haddock Jan 1981

A Mini-Computer Based General Purpose Interactive Computer Graphics Software System, Victor M. Haddock

Retrospective Theses and Dissertations

This research paper presents the description of a Mini-Computer Based General Purpose Interactive Computer Graphics Software System; which has been installed at the University of Central Florida, College of Engineering PDP 11/34 computer system. This system is a simplified version of MOVIE.BYU. MOVIE.BYU is a General Purpose Interactive Computer Graphics Software System that requires a computer with a word length of at least 32-bits. The MOVIE.BYU system was developed at the Brigham Young University, Utah. Extensive modification was required in order to satisfy the PDP 11/34 FORTRAN IV compiler. In addition, the program routines have been overlayed in order to …


Pore Size Distribution Of Sandy Soils And The Prediction Of Permeability : Interim Report, Charng-Hsein Juang Jan 1981

Pore Size Distribution Of Sandy Soils And The Prediction Of Permeability : Interim Report, Charng-Hsein Juang

JTRP Technical Reports

No abstract provided.


A Laboratory Evaluation Of Leachate From The Jim Bridger Power Plant Scrubber Wastes, V. Dean Adams, Mary E. Pitts, Megan J. Dyer Jan 1981

A Laboratory Evaluation Of Leachate From The Jim Bridger Power Plant Scrubber Wastes, V. Dean Adams, Mary E. Pitts, Megan J. Dyer

Reports

Introduction: Scrubber wastes obtained in an affort to limit air pollution generated by coal-fired pwoer plants may contribute to another possible sources of pollution. To date, scrubber wastse have been in a liquid phase which causes disposal problems partially due to the liquid characteristics. The use of solid scrubber wastes and the land deposition of such wastes is proposed. The feasibility of solid scrubber wastes disposal in landfills is under question. The primary area of concern is the effect that water percolation through such wastes would have on groundwater quality parameters. Contamination could result either as precipitation travels downward through …


Use Of Mycorrhizal Inoculation For Plant Establishment On Highway Sites : Interim Report, Stephen Dunning Verkade, David Foster Hamilton Jan 1981

Use Of Mycorrhizal Inoculation For Plant Establishment On Highway Sites : Interim Report, Stephen Dunning Verkade, David Foster Hamilton

JTRP Technical Reports

No abstract provided.


Development Of A Laboratory Technique To Quantify Concrete Curing, Ephraim Senbetta Jan 1981

Development Of A Laboratory Technique To Quantify Concrete Curing, Ephraim Senbetta

JTRP Technical Reports

No abstract provided.


Treatment Of Sanitary Wastes At Interstate Rest Areas, James E. Etzel Jan 1981

Treatment Of Sanitary Wastes At Interstate Rest Areas, James E. Etzel

JTRP Technical Reports

No abstract provided.


Erosion Inhibitor Performance Evaluation Under Simulated Wind And Rain, C. Earl Israelsen, Eugene K. Israelsen, William N. Mcneill Jan 1981

Erosion Inhibitor Performance Evaluation Under Simulated Wind And Rain, C. Earl Israelsen, Eugene K. Israelsen, William N. Mcneill

Reports

Introduction: Increasing public awareness of the desireability of protecting the environment from soil erosion caused by wind and water has centered attention on large construction projects such as highways and housing subdivisions, as well as on individual building sites and parking lots. If unattended, sediment produced from these areas pollutes surface water, restricts drainage, fills reservoirs, damages adjacent land, and upsets the natural ecology of lakes and streams. The search continues for products and practices that will prevent of lessen the amount of sediment leaving construction sites. Products currently in use include chemical as well as organic materials, and they …


Evaluation Of Particular Mulches For Fostering Plant Growth And Inhibiting Erosion (Phase 2), C. Earl Israelsen, Eugene K. Israelsen, William N. Mcneill Jan 1981

Evaluation Of Particular Mulches For Fostering Plant Growth And Inhibiting Erosion (Phase 2), C. Earl Israelsen, Eugene K. Israelsen, William N. Mcneill

Reports

Introduction: Increasing public awareness of the desireability of protecting the environment from soil erosion caused by wnid and water has centered attention on large construction projects such as highways and housing subdivisions, as well as on individual building sites and parking lots. If unattended, sediment produced from these areas pollutes surface water, restricts drainage, fills reservoirs, damages adjacent land, and upsets the natural ecology of lakes and streams. The search continues for products and practices that will prevent or lessen the amount of sediment leaving construction sites. Products currently in use include chamical as well as organic materials, and they …


The Occurrence Of Trihalomethane Compounds In Salt Lake City And Ogden, Utah, Drinking Water Supplies, Thomas Peters, V. Dean Adams, Dennis B. George Jan 1981

The Occurrence Of Trihalomethane Compounds In Salt Lake City And Ogden, Utah, Drinking Water Supplies, Thomas Peters, V. Dean Adams, Dennis B. George

Reports

A purge and trap, gas chromatography system was developed to analyze for trihalomethane (THMs) compounds at the ppb (parts per billion) level in drinking water. Monthly influent and effluent samples were taken from three Weber Basin Water Conservancy Distrcit treatment plants, three Salt Lake City water treatmetn platns, and one Slat Lake Metropolitan water treatment plant. In addition tap water samples were taken at various business and residential locations in Salt Lake City, Utah, and Ogen, Utah. All samples were analyzed for trihalomethanes and total organic carbon (TOC). In addition to monthly sampling, a comparison of the production of THMs …


The Kinetics Of Rotating Biological Contactors Treating Domestic Wastewater, Abraham Pano, E. Joe Middlebrooks, J. H. Reynolds Jan 1981

The Kinetics Of Rotating Biological Contactors Treating Domestic Wastewater, Abraham Pano, E. Joe Middlebrooks, J. H. Reynolds

Reports

Four, four-stage, laboratory scale rotating biological contactor (RBC) units were employed to develop kinetic models for the RBC process when treating domestic wastewater. The study was conducted at three different temperatures of 5 degrees C, 15 degrees C, and 20 degrees C. Each unit operated at a different constant organic loading rate taht ranged from 4 qCOD/m^2/d to 14 gCOD/m^2/d and at a constand detention time of 2 hours. Carbonaceous substrate removals measured as COD cencentrations with the four-stage RBC's were 80, 85, and 90 percent for 5 degrees C, 15 degrees C, and 20 degrees C, respectively. The major …


Design Considerations In The Use Of Glauber Salt For Energy Storage, Duane G. Chadwick, Kim H. Sherwood Jan 1981

Design Considerations In The Use Of Glauber Salt For Energy Storage, Duane G. Chadwick, Kim H. Sherwood

Reports

Various design concepts for the utilization of the latent heat of Glauber salt at temperatues between 25 degrees C and 50 degrees C were studied. Consideration was given to system economics and what particular heat storage system if perfected would be most cost effective. The problems of limited crystal size and heat transfer into and out of salt crystals is discussed. Crystal size is affected by the degree of agitation the salt solution experiences during the salt cooling process. Consequently, crystal size was moderated in a favorable way by introducing air bubbles at the bottom of the salt container. As …


Evaluation Of Wastewater Filtration, Bryant L. Benth, E. Joe Middlebrooks, Dennis B. George, James H. Reynolds Jan 1981

Evaluation Of Wastewater Filtration, Bryant L. Benth, E. Joe Middlebrooks, Dennis B. George, James H. Reynolds

Reports

Tertiary filtration of secondary wastewater is frequently used to improve wastewater treatment plant effluent quality. Four experimental filter columns were operated at the Preston, Idaho, Wastewater Treatment Plant to evaluate the effectiveness of granular media, gravity filtration. The Preston plant is a trickling filter secondary treatment plant and services a population of approximately 3600 people. Four filter medium configurations were studied. Multi-media, dual-media, and single-media beds were constructed with the following media configurations: (1) coal-sand-garnet; (2) coal-sand; (3) sand-garnet; and (4) all sand. The filters were operated at two hydraulic loading rates. Effluents from the primary clarifier, trickling filter, and …


A Determination Of The Energy Storage Capacity Of The Diels-Alder Reaction Between Methylfuran And Maleic Anhydride As Applied To Storing Solar Energy, Brent Gregory Sparks Jan 1981

A Determination Of The Energy Storage Capacity Of The Diels-Alder Reaction Between Methylfuran And Maleic Anhydride As Applied To Storing Solar Energy, Brent Gregory Sparks

Masters Theses

“The heat storage capacity of the Diels-Alder reaction between 2-methylfuran and maleic anhydride is calculated using reaction parameters obtained from solution calorimetry. An equilibrium constant of .614 1/mol and a heat of reaction of 14.33 Kcal/mole were obtained from experiments at 45°C. A reaction ΔCp of -21.8 cal/mole was calculated from heat capacity information at 25°C. From these parameters, a solution initially seven molar in methylfuran and maleic anhydride was found to have a maximum apparent volumetric heat capacity of about 1.85 times that of water. This maximum occurs at about 335 K. Typical active solar energy schemes operate …


H & V News Jan 1981

H & V News

Building Services Engineering

No abstract provided.


A Study Of The Models Describing Fines And Filler Retention By Utilizing Cationic Starch As The Retention Aid, Nen-Sen Chen Dec 1980

A Study Of The Models Describing Fines And Filler Retention By Utilizing Cationic Starch As The Retention Aid, Nen-Sen Chen

Masters Theses

Fines and filler retention under dynamic conditions was studied in this thesis work. Zeta potential of samples are also measured. Dynamic Retention/Drainage Jar and Lazer-Zee Meter were used to accomplish this work. The results have been analyzed by statistical methods. When cationic starch was utilized as a retention aid the pH affected its efficiency, probably because the charge of cationic starch was dependent on pH. This effect was detected by utilizing two-way analysis of variance to find the sources of its interactions with molecular weight and agitation rate. The mechanism was thus determined. At pH 3 and 4, charge neutralization …


H & V News Dec 1980

H & V News

Building Services Engineering

No abstract provided.


Mapping Of Fresnel’S Interface Reflection Coefficients Between Normal And Oblique Incidence: Results For The Parallel And Perpendicular Polarizations At Several Angles Of Incidence, Rasheed M.A. Azzam Oct 1980

Mapping Of Fresnel’S Interface Reflection Coefficients Between Normal And Oblique Incidence: Results For The Parallel And Perpendicular Polarizations At Several Angles Of Incidence, Rasheed M.A. Azzam

Electrical Engineering Faculty Publications

The functions, w = ƒ(z), that describe the transformation of Fresnel’s reflection coefficients of parallel and perpendicularly polarized light between normal and oblique incidence, as well as their inverses, z = g(w), are studied in detail as conformal mappings between the complex z and w planes for angles of incidence of 15, 30, 45, 60, and 75°. New nomograms are obtained for the determination of optical properties of absorbing isotropic and anisotropic media from measurements of reflectances of s- or p-polarized light at normal and oblique incidence.


Feasibility Of Quasi-Random Band Model In Evaluating Atmospheric Radiance, Navin Mirakhur Oct 1980

Feasibility Of Quasi-Random Band Model In Evaluating Atmospheric Radiance, Navin Mirakhur

Mechanical & Aerospace Engineering Theses & Dissertations

The use of the quasi-random band model in evaluating the upwelling atmospheric radiation is investigated. The spectral transmittance and total band absorptance are evaluated for selected molecular bands by using the line-by-line model, quasi-random band model, exponential sum fit method, and empirical correlations, and these are compared with the available experimental results. The atmospheric transmittance and up­ welling radiance have been calculated by using the line-by-line and quasi-random models and are compared with the results of an existing program called LOWTRAN. The results obtained by the exponential sum fit and empirical relations are not in good agreement with experimental results …


Osmotic And Mean Activity Coefficients Of Libr And Lic In Methanol At 25, 35, And 45 Degrees C, Peggy Tomasula Sep 1980

Osmotic And Mean Activity Coefficients Of Libr And Lic In Methanol At 25, 35, And 45 Degrees C, Peggy Tomasula

Theses

Vapor pressure depression data of LiBr and LiCl in methanol at temperatures of 25,35, and 45°C were measured in the molality range 0.1-4.4m using a static method, where the difference in vapor pressure of the electrolytic solution is compared to that of pure methanol.

Osmotic coefficients were calculated from the vapor pressure data. This data was then correlated with both the one parameter Bromley equation and the three parameter Pitzer equation. For all systems at all temperatures, the data were better correlated by the Pitzer equation than with the Bromley equation. Mean activity coefficients of the two salts at the …


Determination Of The Optic Axis And Optical Properties Of Absorbing Uniaxial Crystals By Reflection Perpendicularincidence Ellipsometry On Wedge Samples, Rasheed M.A. Azzam Sep 1980

Determination Of The Optic Axis And Optical Properties Of Absorbing Uniaxial Crystals By Reflection Perpendicularincidence Ellipsometry On Wedge Samples, Rasheed M.A. Azzam

Electrical Engineering Faculty Publications

Given an arbitrarily cut uniaxial crystal wedge, a procedure is described using reflection perpendicular-incidence ellipsometry (PIE) for (1) locating the optic axis, and (2) determining the ordinary (No) and extraordinary (Ne) complex refractive indices. The optic axis is located by finding the principal directions of the two wedge faces and subsequently solving three spherical triangles. No and Ne are determined by two complex ratios of principal reflection coefficients (of light normally incident on and linearly polarized along the principal directions of each face) as measured by PIE. The solution for No and N …


H & V News Sep 1980

H & V News

Building Services Engineering

No abstract provided.


Face-To-Face Vs. Computerized Conferences : A Controlled Experiment. Volume I: Findings, Computerized Conferencing & Communications Center, Starr Roxanne Hiltz, Kenneth Johnson, Charles Aronovitch, Murray Turroff Aug 1980

Face-To-Face Vs. Computerized Conferences : A Controlled Experiment. Volume I: Findings, Computerized Conferencing & Communications Center, Starr Roxanne Hiltz, Kenneth Johnson, Charles Aronovitch, Murray Turroff

Computerized Conferencing and Communications Center Reports

This is a report on the first controlled experiment conducted as part of a four year effort to explore the feasibility and effectiveness of using the computer to structure the communication for various types of group tasks. It uses a language called INTERACT, developed as part of this grant effort, to administer all instructions and conduct a group problem solving discussion in a computer conference. The experiment compares the process and outcome of face to face vs. computer mediated group problem solving discussions.

The objectives of this experiment are the following "basic research" questions:

  1. To gain quantified and detailed knowledge …


H & V News Aug 1980

H & V News

Building Services Engineering

No abstract provided.


Filtration Of Detained Stormwater Through Sand And Alum Sludge For Water Quality Control, Claude L. Cassagnol Jul 1980

Filtration Of Detained Stormwater Through Sand And Alum Sludge For Water Quality Control, Claude L. Cassagnol

Retrospective Theses and Dissertations

Stormwater detention systems as they are frequently designed do not provide good water quality control of stormwater runoff. A filtration media to be used in conjunction with detention ponds to improve their pollutant removal efficiencies was tested at the University of Central Florida and found to be effective. The filtration media, which consisted of a mixture of sand and alum sludge, substantially improved effluent water quality. Average reductions of over 80 % were observed in concentrations of dissolved orthophosphorus, total orthophosphorus and total phosphorus. Reductions were also experienced in iron, aluminum, copper and zinc concentrations. A prototype filtration model is …