The environment has been exposed to a number of hazardous chlorinated
organic compounds. These compounds may be anaerobically biotransformed by
sequential reductive dechlorination reactions in which the chlorine atoms are
replaced with hydrogen atoms. Because reductive dechlorination processes may
occur very slowly in the environment and chlorine position affects the...
This investigation deals with the chaotic rocking response and overturning
stability of offshore equipment subjected to base excitations due to wave-induced
motions of the supporting compliant offshore structural system. The equipment
compliant structural system is modelled as a free-standing rigid object subjected
to horizontal and vertical base accelerations. Three of...
The objective of this study was to develop a numerical model for the movement
and fate of chlorinated phenols in groundwater. In the first part, a numerical model for
several different equilibrium and nonequilibrium sorption processes under isothermal
conditions is developed for one-dimensional, steady-state water flow in soil columns.
The...
Daily evaporative flux and meteorological data from three sites were
collected and analyzed. Analysis included evaluation of several
reference evapotranspiration estimating methods which were theoretically
based on distinct physical laws. The estimating methods included pan
evaporation, energy-based Priestly-Taylor, and combination methods with
and without biological adjustments. The data set represented...
Chlorinated low molecular weight solvents have been discovered in a number of the nation's groundwater supplies. Remediation of these aquifers will require some form of treatment. Presently, the dominant treatment method is air stripping which results in transfer of the solvent from the aqueous phase into the atmosphere. Biodegradation is...
Knowledge of a compound's degradation pathway is crucial to the assessment of risk at contaminated sites. Pentachlorophenol and its metabolic products can serve as model compounds to study the fate and transport of halogenated aromatic compounds in the environment. Acclimation of anaerobic sewage sludge to pentachlorophenol produced a microbial consortium...
This dissertation describes the development of a mechanistic
overlay design procedure. The mechanistic analysis represents a new
trend in both new pavement and overlay design. The greatest advantage
of the mechanistic pavement analysis is that it considers the
fundamental characteristics of materials to be used, is capable of
considering changes...
Adsorptive bubble-separation processes are used to
remove adsorptive contaminants from wastewater. A
mathematical model was developed for the adsorptive bubble
separation processes in a countercurrent column. The model
included an assumption that linear adsorption of the solute
occurred on the gas bubbles. Predictions indicated that
aqueous column height has less...
This study involves the development of a biofilm
reactor that supports growth of a deep biofilm on a gas
permeable membrane. The reactor solution is not aerated,
and oxygen is supplied through the membrane. The reactor
is termed a substratum-aerated-biofilm reactor or SAB.
With adequate concentrations of electron-donors and
electron-acceptors,...
Studies are currently underway to determine the suitability of Yucca Mountain
in Nevada as the nation's first high-level nuclear waste repository. Values of net
infiltration are required to determine pre-waste emplacement groundwater travel times
and the performance of the repository as a waste containment system. The objective of
this study...
This report details the derivation of an analytical model for a flexible membrane
wave barrier. The wave barrier consists of a thin flexible membrane suspended in the
water column by a moored cylindrical buoy on the free surface and fixed to a hinge at
the seafloor.
The analytical model combines...
Chlorinated phenols are toxic compounds and often released into natural
environments from improper disposal or non-point sources. One important factor in
assessing the environmental fate and transport is the rates of microbial degradation in
soils and natural waters. In this study, eight chlorophenols (4-chlorophenol (4-CP),
2,4-dichlorophenol (2,4-DCP), 3,4-dichlorophenol (3,4-DCP), 3,5-dichlorophenol...
Maximum equilibrium scour depths, equilibrium scour volumes,
and induced equilibrium movements at isolated obstacles on river
beds were investigated in clear-water scour. The research was
achieved by a systematic flume study based on the results of
dimensional analysis of local scour.
The main tested obstacles for local scour were cubes....
Land application of industrial wastewater with high levels of nitrogen requires
adequate management practices to prevent groundwater pollution by nitrates. In this study
a predictive computerized model was developed for nitrate leachate concentrations
resulting from land application of wastewater onto crop systems including poplars. The
study included a literature review,...
Implementation of a small-scale irrigation project in southern Mauritania is analyzed in
this report. The main objective is to demonstrate that small-scale irrigation farming is
the best suited solution for Mauritania's agriculture. To reach this objective different
steps are taken in this study. The first step highlights the different aspects...
Groundwater resources have become seriously threatened
due to improper use by industrial, municipal, and even public
sectors. Widespread contamination of aquifer systems has
jeopardized human health and the environment and methods for
restoring these systems are needed. Biological and chemical
in situ remediation, where contaminants are degraded within
the natural...
Thermal cracking of asphalt concrete pavements is responsible for millions
of dollars in annual maintenance and rehabilitation costs in the United States and
Canada. Thermal cracking is typically associated with low temperatures in
northern climates and at high elevations. However, another form of thermal
cracking, known as thermal fatigue cracking,...
The response of lightweight equipment in structures supported on
resilient-friction-base isolators (R-FBI) subjected to harmonic ground motion and various
earthquake ground motions is examined. The equipment-structure base system is modeled
as a three degree-of-freedom discrete system (SDOF subsystems). An efficient
semi-analytical numerical solution procedure for the determination of equipment response...
A general analytical framework was established to investigate the scale-related variabilities in remote
sensing. The variabilities were studied first by investigating canopy structure, canopy interaction with
light, relation between spectral reflectance and plant phenological parameters. The variabilities
simulated by the plant model were compared with the actual spectral data acquired...
A comprehensive system to locate and track objects in two or three
dimensional space, using non-contact video sensing techniques is described. The
need exists to be able to quantify range and proximity of objects that would be
difficult or impossible to measure using standard contact based sensor technology.
Available video...
The decision to bury high level nuclear wastes in deep geological formations
led to the study of the Hanford Nuclear Reservation as one of three possible sites for
the first nuclear waste repository in the United States. To adequately evaluate the
environmental impact of siting nuclear waste repositories in basalt...
Thermal distress in asphalt concrete pavements is a widespread problem around
the world. Thermal cracking can be divided into two modes of distress: low
temperature cracking and thermal fatigue cracking. Low temperature cracking results
from extremely cold temperatures; thermal fatigue cracking results from daily
temperature cycles.
Low temperature cracking is...
The circular wave basin provides a means of physically modeling the nearshore
without the typical problems associated with end walls. Three different coastal
processes were examined to demonstrate the use of a spiral wavemaker in a circular
wave basin. These were longshore currents, shear waves, and groin circulation. A
beach...
Environmental factors such as temperature, air, and water can have a profound
effect on the durability of asphalt concrete mixtures. In mild climates where good
quality aggregates and asphalt cement are available, the major contribution to
deterioration may be due to traffic loading and the resultant distress is manifested
in...
Soil column studies were performed on a chromium contaminated soil from the United
Chrome Products Superfund Site currently undergoing a pump-and-treat cleanup process. The
goal of the research was to provide insight into the feasibility of chemically changing the injection
fluid of the pump-and-treat system to enhance hexavalent chromium (Cr(VI))...
Complex nonlinear and chaotic responses have been recently observed in various
compliant ocean systems. These systems are characterized by a nonlinear mooring
restoring force and a coupled fluid-structure interaction exciting force. A general class
of ocean mooring system models is formulated by incorporating a variable mooring
configuration and the exact...
With the passage of the American with Disabilities Act (ADA) it has become a civil
rights violation to deny access to persons with disabilities to public transportation. The
ADA requires transit agencies to provide accessible buses or equivalent services to
persons with mobility, sensory or cognitive impairments. This study examines...
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...
Statistically-based estimation techniques are presented
in this study. These techniques incorporate structural test
data to improve finite element models used for dynamic
analysis.
Methods are developed to identify optimum values of the
parameters of finite element models describing structures.
The parameters which may be identified are : element area,
mass...
A study of phosphorus loading and water quality implications was conducted for
the Oregon coastal lakes. The study was based on existing data for lake total phosphorus
concentrations and for watershed land uses. A phosphorus mass-balance model was
developed to predict lake total phosphorus concentrations from estimated phosphorus
loading from...
An optimization methodology, algorithms, and computer program for
cable/lumped-body deployment system are developed for the design and installation of
sonar packages in deep ocean ranges. In addition, a methodology and algorithms for the
control of the system are proposed.
A penalty function is developed in terms of the system parameters...
A time-domain model was developed to predict the fluid/structure
interaction of a three-dimensional deformable body in a fluid domain subject to
long-crested finite amplitude waves. These nonlinear waves induce transient
motion in the body. In turn, the interaction of the body with the waves modifies
the wave field, causing additional...
The use of municipal refuse (RDF) as fuels has
received widespread attention for reason of its energy
equivalence and the increasing lack of available landfill
sites. The principal obstacle to the construction of combustion
facilities is that RDF produces toxic compounds,
including heavy metals and such organic compounds as PCDD...
Stability analysis of truss chords loaded by a
combination of axial and lateral forces is studied. A
simple model based on beam-column theory is proposed and
analyzed. The continuous truss chord is replaced by a beam column
loaded by end moments replacing the effect of
adjacent members. The solution yields...
The success of civil engineering construction in cold regions often depends on the
assessment of the potential for frost heave. Over the past two decades two models have
been presented to the engineering community to identify the frost heave potential,
namely: (1) the segregation potential (SP), and (2) the discrete...
Low temperature cracking is attributed to tensile stresses induced in an
asphalt concrete pavement that develop when the pavement is subjected to a cold
temperature. Cracking results in poor ride quality and a reduction in service life of
the pavement. Low temperature cracking has been predicted by regression
equations, mechanistic...
Rotating machine play an important role in modern technology. Compressors in
ventilating and cooling systems, pumps in power generation facilities, as well as high
speed computer are all examples of flexible rotating machinery that must remain functional
during and after a sever earthquake. Recent earthquakes have demonstrated that an
aseismically...
The Environmental Conditioning System (ECS) was designed to evaluate the
water sensitivity of asphalt concrete mixtures. The ECS subjects asphalt concrete specimens to a series of conditioning cycles including water flow, elevated and/or lowered temperature, and repeated axial loading. The purpose of this research was to: (1) evaluate the ECS...
The Melnikov method is applied to a model of parametrically generated cross-waves in a long rectangular channel in order to determine if these cross-waves are chaotic. A great deal of preparation is involved in order to obtain a suitable form for the application of the Melnikov method. The Lagrangian for...
Stochastic analysis procedures have been recently applied to analyze nonlinear
dynamical systems. In this study, nonlinear responses, stochastic and/or chaotic, are
examined and interpreted from a probabilistic perspective. A multi-point-moored
ocean structural system under regular and irregular wave excitations is analytically
examined via a generalized stochastic Melnikov function and Markov...
Asphalt concrete pavement is subjected to several damaging actions from traffic
loads, water (from precipitation and/or groundwater sources), and temperature. The
durability of the asphalt-aggregate mixture, its ability to withstand these damaging
actions for long periods, is a very important engineering property. While the durability
of the asphalt-aggregates mixture depends...
Groundwater contamination on irrigated land is of concern in this nation
and around the world. In order to reduce the potential of groundwater
contamination by agricultural practices such as irrigation, fertilizer and pesticide
application, vadose-zone monitoring and sampling are needed. The main
objective of this study was to evaluate impacts...
Radon-222 gas has unique properties allowing it to be used as an indicator for the
presence of organic phase liquids in the saturated zone. It naturally occurs in soils. It is
radioactive, making quantitative detection straight forward. A noble gas, it is chemically
inert and does not react with aquifer...
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...
This study investigated the laboratory performance of crumb rubber modified
mixtures compared to a standard bituminous mixture using performance based test
procedures. This study was part of an asphalt resurfacing program for the Seattle
Washington area. Laboratory analyses were used to estimate the long term pavement
performance of these mixtures...
This research was conducted as part of the Strategic Highway Research Program (SHRP)
A-003A contract at Oregon State University to validate the findings of SHRP contracts
A-002A and A-003B with regard to aging of asphalt-aggregate mixtures. One short-term
and four long-term aging methods were used to simulate aging of asphalt-aggregate...
The incipient motion of sediment particles in gravel-bed
rivers is a very important process. It represents the
difference between bed stability and bed mobility. A field
study was conducted in Oak Creek, Oregon to investigate
incipient motion of individual particles in gravel-bed
streams. Investigation was also made of the incipient...
Recent developments in estimation of the survivability of a U.S. Navy transport barge in random seas are extended to improve accuracy. The single Degree-of-Freedom (DOF) model of a extreme roll response of a barge used in previous research is replaced by a 3-DOF roll-heave-sway model to include linear and nonlinear...
A technique is developed and tested to analyze the interaction of flowing water,
bed topography, and bedload sediment transport in meandering channels where gravel
bars are removed. The method relates the local velocity distribution, bed shear stress and
sediment transport conditions to the local bed configuration in river bends before...
Continuous-flow and batch experiments were conducted with a column reactor
system containing Hanford aquifer material in order to evaluate the potential of in-situ
bioremediation of carbon tetrachloride (CT) at Hanford. The effectiveness of benzoate
and acetate as primary substrates was considered. Nitrate and sulfate were potential
electron acceptors. Transport experiments...
Quality Function Deployment (QFD) is a product development process that
assures the needs and desires of the customer are heard and heeded during the
design, development and production of a product. Though it has been used
successfully in other industries, only a few companies in the U. S. Engineering
and...
Large quantities of unused heavy oil and residual waste products from the petroleum refining industry were deposited in on-site landfills, pits, and lagoons, prior to the promulgation of regulations governing their disposal and technology development that would further utilize and/or recycle these materials.
Contacting petroleum products with sulfuric acid for...
A mix-culture of methanogenic and sulfate-reducing bacteria was capable of degrading trichloroethylene (TCE) to dichloroethylene (DCE). The culture was incubated under anaerobic conditions within a soil sample taken from Gilbert-Mosley site, Wichita, Kansas. To stimulate the growth of indigenous bacteria, a carbon and energy source was added in this microcosm...
Persistence of Non aqueous phase liquids (NAPLs) in the subsurface at residual
saturations eventually contributes to undesirable groundwater contamination. Proper
characterization of subsurface NAPL, its location, composition and distribution, is
essential for the chosen remediation technology to be effective. It is also desirable to
assess the performance of remedial actions...
In situ bioremediation of pentachlorophenol-contaminated ground water in a sequential anaerobic-aerobic down borehole permeable barrier reactor requires a non-toxic primary substrate for dichlorophenol cometabolism. Serum bottle tests comparing the effectiveness of eight primary substrates for aerobic dichlorophenol degradation showed phenol to be the most effective followed by imitation vanilla flavoring,...
This study defines the information gathering and communication and response
needed for safety at highway-rail crossings. It examines technologies for low-cost,
high-safety treatments for low volume highway crossings of higher speed (130-200 kph) rail. Crossing closure and consolidation is a necessary first step. Existing
train control and crossing safety systems...
The (nonlinear) response behavior of a piecewise-linear system is investigated under
both deterministic and stochastic excitations in this study. A semi-analytical procedure is
developed to predict the system behavior by evaluating the joint probability density functions
of the Fokker-Planck equations of the stochastic piecewise-linear system under random
excitations via a...
Cometabolic biodegradation processes, important for bioremediation of hazardous waste sites, are not well understood and have not been modeled thoroughly. Toxic effects and bacterial responses to toxicity may change intracellular enzyme levels, rendering traditional enzyme kinetics models inappropriate. This document presents a novel cometabolic enzyme kinetics model that incorporates enzyme...
The dissertation uses state-of-the-art structural engineering theories, in parallel with the modern and still-developing control theory of electrical engineering to mitigate the vibratory responses of a double-stayed bridge subjected to strong earthquake ground motions.
First, a nonlinear finite element model of the double-stayed bridge subjected to non-uniform (multi-support) earthquake excitations...
Time-domain models were developed to predict the response of a tethered buoy
subject to hydrodynamic loadings. A coupled analysis of the interaction of a buoy and
its mooring is included and three-dimensional response is assumed. External loadings
include hydrodynamic forces, tethers tensions, wind loadings and the weight of both
cable...
This thesis presents an examination of the nearshore wave bottom boundary layer
under conditions of significant sediment response. Using both field observations and
simple models, the response of the bottom boundary layer to random waves is shown to
have a complex behavior. First, the linearized wave bottom boundary layer governing...
Understanding the processes involved in the transport of dissolved gas plumes in groundwater aquifers is essential for comprehending the effect that these transport processes can have on site characterization and remedial design applications. Previous laboratory and field studies have indicated that dissolved gas transport in groundwater can be greatly affected...
Batch microcosm studies were carried out to screen for microorganisms from the
subsurface of Hanford DOE site that could cometabolically transform chloroform (CF)
under aerobic conditions. The potential need for CF bioremediation at the Hanford site
has resulted from the large release of carbon tetrachloride (CT) to the subsurface, of...
Ex-situ bioremediation of saturated soil contaminated with pentachlorophenol and
2,3,5,6-TeCP is commonly accomplished by landfarming or by treatment in a bioreactor.
Treating saturated, low-permeability soils in bioreactors, without pre-treatment requires a
reactor capable of promoting anaerobic and/or aerobic removal of chlorophenols without
transferring these contaminants to the aqueous phase. A...
The composite FRP rebars research at Oregon State University was initiated in
1993 principally to develop a non-metallic hollow reinforcement. It was recognized that
the tensile properties of such reinforcement are unquestionably superior to steel, but its
performance in concrete could be problematic. The bond between FRP rebars and
concrete...
Environmental factors and physical properties of latex modified concrete (LMC)
are hypothesized to contribute to early age cracking in bridge deck overlays. Cracking
permits the ingress of moisture and aggressive solutions into the substrate and may
contribute to other subsequent distresses. Understanding the material properties and
mechanisms involved is necessary...
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...
The seismic performance of port structures has been well documented following
recent earthquakes, and indicates that port structures are highly susceptible to earthquake-induced
damages. These damages are primarily due to soil liquefaction and the associated
ground failures. Sheet pile bulkheads provide vital intermodal and lifeline transportation
links between water-side and...
The combination of increased training tempo due to military base closures and the reduction in military budgets have placed a severe burden on the infrastructure at many military installations and emphasized the need for an integrated facility management support system. This research involved linking existing facility, environmental, and operational data...
Cometabolic biodegradation processes are potentially useful for the
bioremediation of hazardous waste sites. In this study the potential application of phenol-oxidizing
and nitrifying bacteria as "priming biocatalysts" was examined in the
degradation of polycyclic aromatic hydrocarbons (PAHs), aryl ethers, and aromatic
ethers. We observed that a phenol-oxidizing Pseudomonas strain cometabolically...
Base isolation is an alternative seismic design strategy in which the primary structures
and their internal components are uncoupled from the potentially damaging horizontal
components of an earthquake by base isolators which attenuate the transmission of
horizontal acceleration into the system. Rotating machines are among the key internal
components of...
At Site-300, Lawrence Livermore National Laboratory (LLNL), CA,
trichloroethene (TCE) is present along with tetraalkoxysilanes such as tetrabutoxysilane
(TBOS) and tetrakis(2-ethylbutoxy) silane (TKEBS), as subsurface contaminants.
Intrinsic transformation of TCE to cis-dichloroethene (c-DCE) was observed in the
groundwater at locations co-contaminated with TBOS or TKEBS. Attenuation of TBOS
and TKEBS...
Attention has been drawn to the observation that environmental benefits under the current regulatory approaches are diminishing with respect to increased pollution control costs. Regulators have begun to appreciate that while environmental gains can still be achieved under the current command and control system, the most significant environmental gains have...
The undermining of bridge foundations can lead to either costly repairs or a bridge
collapse. These foundations must be designed to counter the effects of scour. Current
practice does not allow for accurate estimates of scour in erodible rock. Scour in rock can be related to geotechnical and hydraulic properties....
In 1996, Beach et al. first proposed the idea of mounting an echo-sounder on a Waverunner to measure nearshore beach profiles. This thesis discusses the Coastal Profiling System, an extension of the original work, which has been utilized to measure nearshore bathymetry at selected sites along the coasts of North...
Several potential sorbent materials containing iron oxides were prepared and evaluated for potential to remove divalent metals from waste waters. These included a ferrihydrite-coated sand, maghemite incorporated in Dowex[Trademark] ion exchange resin, gothite and two thermally activated ferrihydrites. Attempts to prepare sorbents from steel shot by coating with ferrihydrite or...
Recent concern over the potential environmental impact of highway construction
and repair materials on surface and ground waters has lead to extensive laboratory
screening and subsequent testing of a set of new materials and waste amended mixes. As
part of Phase II of a three-phase project for the National Cooperative...
The reductive dechlorination of chlorobiphenyls in sediment by titanium(III) citrate-reduced vitamin Bus was studied in batch reactors. Long term ampoule studies demonstrated reductive dechlorination of sediment-sorbed 2,3,4,5,6-pentachlorobiphenyl (2,3,4,5,6-PeCB) to tetra-, tri-, di-, and monochlorobiphenyl products. Over 50% chlorine removal was observed over 160 days. The results of the ampoule experiment...
Response behavior of a nonlinear structural system subject to environmental loadings
is investigated in this study. The system contains a nonlinear restoring force due to large
geometric displacement. The external excitation is modeled as a narrowband stochastic
process possessing dynamic characteristics of typical environmental loadings.
A semi-analytical method is developed...
The Wiggins-Holmes extension of the generalized
Melnikov method (GMM) is applied to weakly damped
parametrically excited cross waves with surface tension in
a long rectangular wave channel in order to determine if
these cross waves are chaotic. The Lagrangian density
function for surface waves with surface tension is
simplified by...