Storage of water for water quality control is one of the alternative
means of achieving water quality objectives. Authorities in
the field of water quality management disagree regarding the use of
precious water for the dilution of wastes.
The costs of achieving water quality objectives by treatment
of wastes at...
An investigation was conducted to ascertain if certain concepts
of microbial metabolism, derived from studies using simple
soluble substrates, are applicable to the biological assimilation of
complex, partially colloidal suspensions. A mixture containing one
gram of Carnation dry-skim milk is considered to be a complex,
partially colloidal substrate and was...
The degradation of kraft pulping wastes in estuarine waters
was measured in terms of the following parameters: five-day 20°C
B.O.D., the Pearl-Benson Index, and toxicity to the bay mussel
(Mytilus edulis L.). The waste tested was the total effluent from a
combined pulp and paper mill producing 430 tons of...
A stream's temperature is a major factor in its ability to support
fish life and to be utilized for other beneficial purposes. The
approach most generally used for stream temperature prediction is
the Energy-Budget method, which involves the inventory of all the
energy entering and leaving the stream. A temperature...
The simplified equations of motion proposed by Morton to determine
the extent of vertical travel of a forced plume in a linear
density stratified environment were re-written and solved in a way
which allowed them to be applied to any non linear profile of density.
For application to any specific...
Temperature is one of the most important factors
affecting microbial activity and consequently is of great
importance in a biological waste treatment system. Extensive
research has been carried out to determine the
effects of temperature on biological reactions in the temperature
range of 20° to 35° Centigrade. It is generally...
The nonlinear response of a ten-story steel structure with semirigid
girder connections is studied under conditions of dynamic loading.
The dynamic loading used in this study is the North-South component
of the May 18, 1940 El Centro, California earthquake. To deal
with the complexity of the problem the structure is...
The response of three-dimensional frames subjected to an arbitrary
dynamic force is studied. The method of mode superposition
is used to obtain the frame response solution. Two different modeling
systems are used to idealize the frame. These are the "discrete
mass system" and the "continuous mass system." For an example...
Aerial photography provides a method of analyzing dispersion
of wastes that are discharged into the ocean. This method is more
comprehensive than conventional boat sampling in dispersion studies.
The photographic technique permits waste concentrations to be
measured throughout the plume in one instant; thereby allowing the
diffusion analysis to be...
Computer oriented techniques and procedures are presented for the analysis of single and multiple cable systems. Application is made to a two-point mooring system influenced by surface and subsurface hydrodynamic loading. The effects of the various parameters are presented and the numerical method is compared to exact solutions obtained from...
A method of analysis of arbitrarily shaped prestressed concrete
members for biaxial bending is given. The stress-strain curve of
the concrete is represented by two parabolic segments, and the
effects of strain hardening of the steel are included in the analysis.
An iterative numerical procedure is used to solve for...
A need has existed for an in-depth structural analysis of penstock
bifurcations because they form an integral part of hydroelectric
power plants. Their geometrical complexity has prevented classical
structural analysis from providing an accurate and overall picture of
the stresses in the structure.
Digital computers and the development of finite...
Mathematical modeling of phytoplankton populations based on laboratory observations provides increased understanding of the interaction among the environmental and biological mechanisms. influencing growth dynamics. Such fundamental understanding is necessary to estimate the impact of man-made perturbations on natural population.
A three-compartment mathematical model was developed to represent a phytoplankton population...
This is a fundamental study of the mechanism of protein particle
removal during flow through sandy soil. Mathematical models for
diffusion-adsorption and diffusion-convection-adsorption processes
were developed and compared with experimental data. An attempt was
made to calculate the distance over which the adsorption forces act.
The differential equation for the...
The conventional method for structural design of wood-joist
floors is over-simplified and often results in stronger and stiffer
floors than necessary. There is also a need to include in the floor
design additional criteria dealing with human response to floor vibration
such as that due to walking.
This study develops...
A computer program was developed for analyzing culverts
under earth embankments constructed of compacted cohesive soil
using the finite element method. The culvert-embankment system
is represented as a two-dimensional plane strain problem. The
plane of investigation is taken normal to the culvert axis. The soil-culvert
interface is assumed to be...
The dynamic philosophy of education as applied to the undergraduate Civil Engineering program has been influenced by such factors
as the introduction of new theories, the demands
and needs of our society and the personnel responsible for teaching.
These changes
are reflected in the curriculum as witnessed
by a historical...
Sediment transport in a gravel-bottomed stream located in the Oregon Coast Range was studied to determine the effects of a single
layer of large particles (the armour layer) located at the surface of the bed material. The bed load transport system was studied jointly with suspended sediment transport to understand...
A one-dimensional, implicit, finite-difference model is
developed, calibrated and verified for three estuaries along
the central Oregon coast. The model is used to generate controlled
data for a large number of hypothetical estuaries.
Two non-dimensional coefficients, K[subscript F], and. K[subscript I], are developed
incorporating physical characteristics of the estuary which...
A problem confronting the Corps of Engineers and other water resources planners in the Pacific Northwest is the prediction of anadromous fish enhancement benefits that would result from a proposed high dam project. These benefits are expected from augmenting natural streamflows with relatively cold reservoir withdrawals. The resulting increased streamflows...
A single cell in a 12 cell bulkhead was instrumented to observe
its behavior and confirm design assumptions during construction.
Vibrating wire strain gages were employed to measure horizontal
strains in sheetpiling webs. These were converted to interlock
force at eight locations and three elevations around the cell. The
deformed...
The mean square displacement response of a point on a transmission
line conductor that is subjected to wind gust generated lift forces is
computed. The wind gust velocity and wind gust generated lift forces
are treated as random processes in both time and space. A lift force,
that is velocity...
A mathematical model is developed for the analysis of circular
cell bulkheads subjected to gravity loads of cell fill, backfill, lateral
pressure, and surcharge load using the finite element method. The
finite element circular cell model consists of axisymmetric triangular
and/or quadrilateral ring elements for soil and cylindrical shell elements...
Based upon the Pearson Type VIII distribution function,
a general retention function which relates the saturation to
the capillary pressure in disturbed soils has been discovered.
This simple and yet complete function has been
shown to describe precisely the imbibition as well as the
drainage branch of the retention curve....
An evaluation of fabric reinforcement of the roadway
structure is made. The study includes a parametric analy
sis using layered elastic theory and a series of large
scale model tests.
The parametric. study analyzes the stresses and
strains of roadway structures with a fabric layer between
tna surface layer and...
The biochemical degradation of domestic sludge deposits exposed to benthic marine conditions was investigated using a laboratory Deep Sea Simulator. The rate and extent of deposit stabilization were determined for select hydrostatic pressures and hydrogen acceptor conditions by monitoring depletion of particulate organic carbon in 2.0 and 3.0 centimeter deposits....
Large-scale experiments on circular model cell bulkheads were
conducted to define the distribution of hoop stresses, deflections of
the cells, distortion of the cell fill, ultimate overturning resistance,
and the critical mode of failure. The embedment depth of the model
cells was varied to investigate the effect of embedment on...
Two strategic approaches to water quality control in Oregon's
Willamette River are presently being utilized: point source treatment
and flow augmentation. Dry weather releases from reservoirs are for
authorized purposes other than water quality. Reservoirs can participate
in pollution control by summer flow augmentation where authorized water
resource objectives (flood...
A second-order nonlinear diffraction theory is developed for a
large diameter circular cylinder under the action of surface gravity
waves of finite amplitude in water of-finite depth. Boundary value
problems are derived by using a perturbation expansion and the
solutions for the diffracted waves are given in terms of Fredholm...
Hydrazine based fuels are used by the Air Force for the Titan II
and Minuteman III missiles and the F-16 aircraft and by the National
Aeronautics and Space Administration for propulsion systems and the
Space Shuttle Program. These uses represent significant production,
transportation and storage of these fuels, and, as...
Trace metals in the aquatic environment are generally concentrated
on the surface of solid geochemical phases which eventually become incorporated
into estuarine and marine sediments. The mechanism of trace
metal concentration is believed to be adsorption with various geochemical
phases such as hydrous metal oxides, clays, and organic matter.
Metals...
Geotextiles are synthetic fabrics which may be substituted for
graded aggregate to protect ocean and coastal structures from erosion
and soil instability adjacent to the structure. They are commonly
used as a filter and as a structural membrane between an undisturbed
sediment surface below and an erosion resistant coarse aggregate...
Sediments are the major compartment in aquatic environments for many materials of toxic or nutrient concern. The lack of knowledge of the phase associations of toxic metals in sediments is the largest deficiency in our understanding of the environmental hazard posed by metal contamination. This study examined the sedimentary partitioning...
The nonlinear dynamic analysis of cable and membrane structures
is presented in this study. Attention is given to the nonlinearities
arising from large displacements, from nonlinear stress-strain
relationships and from nonconservative loadings.
The finite element method is used to model the cables and
membranes. Curvilinear geometries of the elements are...
Since the introduction of pure oxygen activated sludge systems in
the late 1960's, proponents have claimed several advantages resulting
from the elevated dissolved oxygen (DO) levels maintained. However,
numerous comparative studies have failed to produce a consensus of
professional opinion regarding the validity of these claimed advantages.
The purpose of...
This dissertation introduces a method which
can simulate multi-dimensional Gaussian random
processes by the superposition of sine functions
The fast Fourier transform technique is incorporated into the simulating method to facilitate
saving of computer time.
In view of the fact that the fast Fourier
transform play important roles in digital...
A growth model is developed for coho salmon which accounts for
temperatures and feeding rates typically encountered in fish hatchery
operation. Feeding rates utilized by the model ranged from
maintenance to maximum utilizable rations. The model is derived from
an empirical equation for maximum growth rate, and a theoretical
equation...
The nonlinear dynamic analysis of cable and cable-large
body systems subject to both deterministic and non-deterministic
loading is presented in this study. Nonlinearities
occur due to large displacements, material nonlinearity,
lack of stiffness in compression, and the non-conservative
fluid loading.
A finite element model is used to model the cable...
A numerical calculation procedure for the hydrodynamic interference effects between large multiple structures interacting with
linear ocean waves is presented in this study. Viscous effects are
neglected and the hydrodynamic pressure forces are assumed to be
inertially dominated. A finite element method which incorporates
radiation boundary dampers is adopted to...
Saudi Arabia currently contains 31000 km (18600 mi)
of paved roads and 42000 km (25200 mi) of agricultural
roads, with the prospect of more roads to be constructed.
The low population (6 million) compared to the large area
of the country (2,253,300 km², 900,000 mi²) coupled with
the high cost...
A complete solution, exact to second-order, for wave motion
forced by a hinged-wavemaker of variable-draft is presented. A
solution for a piston type wavemaker is also obtained as a special
case of a hinged-wavemaker with negative infinite draft. The
existing Stokes inviscid theories for mass transport is extended to
include...
Incipient motion of cohesive sediment and the role of flow
parameters were investigated for separate and combined unidirectional
and oscillatory flows. Sediment from Sturgeon Lake, mainly silt and
clay with organic matter, was used as bed material In recirculating
and wave flumes.
Bench-type experiments indicated that when the submerged sediment...
Regionalized variable analysis has been used to study
a number of meteorological and hydrological variables
including precipitation (Delhomme and Delfinier, 1973),
streamfiow (Villeneuve et al., 1979) and hydraulics of
groundwater aquifers (Gambolati and Volpi, 1979). In the
research work reported in this thesis, an attempt was
made to characterize the...
The purpose of this study was to provide the USDA-Forest Service,
Bureau of Land Management (BLM), and other agencies or industries
that may deal with temporary and intermittent use roads with
the necessary background information for the identification, economic
evaluation, and selection of the alternate surfacing systems and to
determine...