The effects of roadbuilding, logging and burning upon stream
runoff responses to individual storms are evaluated for the Alsea
experimental watersheds, located in the Oregon Coast Range, The
parameters analyzed are peak discharge, induced peak discharge,
time-to-peak, and storm-runoff volume. The volume parameter is
further sub-divided into total, quick, delayed,...
The overall goal of this study was to gain an insight into the load sharing aspect between oriented strand board (OSB) and gypsum wall board (GWB) in shear wall assembly during racking load. More specifically the objectives of the study were to: (1) evaluate qualitatively the load sharing between OSB...
Asphalt pavements constitute more than ninety percent of the nation’s roadway network. Besides serving the key role of providing a smooth and durable all-weather surface that benefits a range of users, they are also the lifelines of the nation and the world and contribute tremendously towards economic and social development....
High water temperatures in rivers have detrimental effects on riverine water quality and ecology. In this study, two river temperature models, within the agricultural watershed model Soil and Water Assessment Tool (SWAT), were investigated for their ability to simulate water temperatures accurately throughout the year. The original temperature model within...
The objective of this study was to provide first order observations of bed level changes occurring in streambed simulated culverts throughout an annual period. To accomplish this, 30 culvert sites were selected in Oregon and Washington, and monitored over, at least, a 2 year period. Streambed scour and redeposition data...
Cob is an earthen building material composed of sand, clay and straw. Though cob homes
are presently being built in the Pacific Northwest, there is no applicable building code for this
material. The purpose of this study is to establish estimates for the major engineering parameters,
including both average values...
The Horsetail Creek Bridge (HCB), constructed in 1914, is located along the Historic Columbia River Highway in Oregon. The original cross beams from the HCB were substantially deficient in shear strength, particularly for the projected increase in traffic loads. One control beam and three beams with varying configurations of a...
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...
Timber-concrete composite (TCC) solutions originated in the early twentieth century. There has been a renewed interest in TCC solutions in modern mass timber buildings, especially for floor systems. However due to lack of data, design standards, and code acceptance, TCC solutions require that new mass timber solutions be tested, and...
As ecoroofs have become more widespread throughout the U.S., it has become increasingly important to understand their structural behavior. The purpose of this research was to investigate the load effects exerted on a roof structure with an ecoroof during rain events and the subsequent drainage period, with the intention of...
The constitutive behavior of high-performance fiber-reinforced cementitious composites (HPFRCCs) under mechanical loading is characterized by significant tensile properties that play an essential role in the structural response of several applications in structural engineering. The significance of tensile properties of HPFRCCs in structural engineering is the focus of three manuscripts presented...
Student engagement in a course plays a vital role in a student’s ability to process and construct knowledge. Student engagement research has investigated how students engage in and out of the classroom on a macro scale, through observation and survey data collection of large student populations, which lack focus on...
As people learn new concepts, they experience a process termed conceptual change. There are several theories that attempt to explain conceptual change, and this paper uses the framework theory to explain how students learn mechanics of materials. Semi-structured interviews with ninety students were qualitatively analyzed for this research in an...
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,...
The Steamboat Creek basin drains 227 mi² (588 km²) of steep forested terrain into the North Umpqua River of Southwest Oregon, 39
mi (63 km) northeast of Roseburg. Summer base flows for Steamboat Creek average 83 cfs (2.35 m³/sec). Steamboat Creek and its
tributaries are considered important to the production...
Reducing the CO2 emitted by the production of cement can greatly reduce the carbon emissions attributable to the built industry. By specifying concrete mixes with lower global warming potentials (GWPs), structural engineers can reduce the carbon emissions of concrete used in the built industry. This thesis uses a cradle-to-gate life...
The main objective of this research study is to incorporate construction worker safety and health into sustainable design and construction practices. This can be fulfilled by the development of an innovative construction worker safety and health planning tool, called Sustainable Construction Safety and Health (SCSH) Rating System that will:
•...
The purpose of this thesis is to examine and compare sustainable design methods used in the United States and Chile, focusing on sustainable materials and certification programs, to see if sustainable design methods used in the United States can be implemented in Chile to further its sustainable development. Through literature...
Alkali silica reaction (ASR) and corrosion of reinforcement are two deterioration mechanisms in reinforced concrete (RC) structures. These deterioration mechanisms can significantly damage a RC structure and reduce its service life. Supplementary cementitious materials (SCMs) are commonly used to improve the durability of RC systems containing reactive aggregate that are...
Dungeness crab is an important fishery on the Pacific Coast.
The processing subsystem of the fishery is hampered by a variety of
problems that have acted to impede technological innovations that
could improve efficiency and sanitation in seafood plants. This paper
provides background for problems encountered by the processors, discusses...
Moisture damage has long been recognized as one of the most
critical factors influencing the performance of asphalt concrete (AC)
pavements. This moistureinduced damage occurs from either the
physical separation of the asphalt film from the aggregate or the
softening of the asphalt binder within the AC mixture in the...
Capacity of transverse 1950's vintage reinforced concrete deck girder bridge bent caps with large straight bar anchorages were investigated and evaluated. Eleven subassemblage column specimens were examined with different anchorage lengths, bar groupings, amount of transverse steel, and externally applied axial force. Test results showed an increase in anchorage capacity...
Cross-laminated timber (CLT) is an attractive building material because it is renewable, promotes fast installation, and possesses a high strength-to-weight ratio. The use of CLT in seismic applications has become increasingly common with the development of post-tensioned CLT rocking wall lateral force resisting systems (LFRS). The CLT pier-and-spandrel system designed,...
The addition of exogenously supplied hydrogen stimulates PCP reductive
dechlorination and increases bacterial growth. While research focuses mainly on
pure cultures, few exist capable of aryl reductive dechlorination, and few markers
exist to identify reductively dechlorinating bacteria within mixed cultures.
Furthermore, most active bioremediation projects stimulate mixed cultures of native...
Directional wave spectra have been estimated in this study based
upon simultaneous subsurface measurements of current and pressure.
Two previously developed methods, the stochastic and deterministic
approaches, have been reviewed and restudied. It is demonstrated by
means of the Correlation Theorem that the stochastic and deterministic
approaches are, under certain...
Turkey is an agricultural country where exchange and shipping of goods has been gravely hampered in the past by lack of highways. The railroads have large expanses of land between them, and highway construction in the past has been limited to strategic roads and connections of cities to railways. Unless...
A test system was developed and used to
investigate ice/structure interaction with centrifugal
modeling. The test system was designed to perform two
main functions: (1) create a uniform ice sheet, and
(2) drive a model structure through the ice sheet at a
constant speed. Both of these functions were required...
A variety of stakeholders require information about marine systems. In the open ocean, pilots of marine vessels require knowledge about environmental conditions for safe passage and route planning. On the coastline, communities rely on information about nearshore dynamics to increase safety from coastal hazards such as nearshore pollutants, coastal erosion,...
Coastal hazards are the result of numerous physical processes cumulatively causing water levels to flood and erode the land. The waves, storm surges, tides, and run-off contributing to elevated water levels are each the product of chaotic and random weather patterns. These stochastic weather patterns dissipate energy in Earth's climate...
A study was conducted to determine the chemical nature and
the biological treatability of log pond water. Various analyses including
total solids, volatile solids, suspended solids, dissolved
oxygen, pH, COD, BOD₅, BOD₂₀, total Kjeldahl nitrogen, nitrate
nitrogen, phosphate, and PBI were performed on water samples
from each of the four...
The treatability of waters from four log ponds in Oregon by
physical and chemical treatment methods
was investigated.
Treatment processes included sand filtration, activated carbon contact and
coagulation with aluminum sulfate.
Preliminary studies were made at each log pond to determine
the homogeneity of the pond water for sampling
purposes...
An attempt to determine the relationship between the computer,
the computer program exchange organization and today's practicing
civil engineer has just been completed. A questionnaire was used to
obtain information and opinions from 850 selected practicing civil
engineers. Based on those questionnaires reaching their addresses,
a return rate of 81.7...
Sediment convergence and divergence zones create subaqueous morphological features that range from ripples O (cm) to coastlines O (km). However, there is a gap in knowledge associated with quantifying the contribution of small-scale ripple mobility to the evolution of large-scale morphology. To address this gap, we investigate how small-scale ripples...
The indiscriminate release of fecal bacteria to the environment
can present a public health hazard when pathogenic species gain access
to drinking and recreational water sources. The extent of bacterial
contamination of surface and ground waters associated with animal
production units and waste application areas seems largely dependent
on the...
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...
By an appropriation of the Oregon Legislature of it becomes possible for the Oregon Agricultural College to build a drill shed, a thing long needed by this institution. Dennis, Hendricks and Tobey, architects of Portland, submitted plans for this drill shed and in designing the truss for this building we...
A continuous flow, gas-permeable-membrane-supported (GPMS) biofilm
reactor was developed to facilitate the treatment of polychlorinated
biphenyls (PCBs). The GPMS biofilm reactor consisted of a cylindrical
glass vessel made up of three compartments: the gas, liquid and
headspace compartments. A gas-permeable membrane separated the bottom
gas compartment from the liquid compartment....
Initially, a small experimental study was undertaken to examine the influence of incline on the frequency of taut cables. The experiments consisted of exciting a short cable at angles of incline from zero to 90 degrees and at various tensions. The results from these experiments shows a small effect due...
The effects of boundary geometry on internal density currents
in a density stratified reservoir were investigated in a laboratory
model. When water was simultaneously withdrawn and admitted to
the reservoir, a complex current regime was established. The general
flow pattern is described, and the influence of physical variables
on the...
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...
The purification capacity of an activated sludge process is highly
dependent of the rate of oxygen transfer from the air to the microorganisms.
This rate can be increased in an air diffusion system by
subjecting the culture to high shear and high pressure.
A study of the effects of high...
A study of the effect of elevated pressure on the activated
sludge waste treatment process is presented. The method of study
involved a comparison of two laboratory, batch type, activated sludge
units. One unit was operated at atmospheric pressure as a base control
and the other operated at elevated pressures...
Engineers, in practice, are often faced with the challenge of evaluating a fire-damaged structure and developing a rehabilitation and retrofit plan. In order to decide on a rehabilitation and retrofit plan, information on thermal degradation of building materials and connections are vital. A critical knowledge gap exists in terms of...
The objective of this study was to determine the effect of misplaced hold-downs
on the static and cyclic behavior of wood shear walls. Three shear wall
configurations were considered in this study. The first configuration (control) had
hold-downs at the ends of the wall (wall type 1), the second configuration...
The research undertaken consisted of the study of three topics
affecting the performance of asphalt concrete mixtures, that is, mixing
moisture, oxidative aging and higher tire pressures and axle loads.
This thesis presents the findings of the research comprising these
three topics.
In the first study, the effects of mixing...
A study of the effect of mixing on the oxygen uptake rate of
estuarine bottom deposits is presented. The method of study involved
the mixing of samples of bottom deposits with the overlying water to
result in concentrations of suspended matter in the same order as
observed in the estuary....
Batch sorption tests were conducted using 3,4-DCP and cellulose triacetate as the sorbate/sorbent pair. Sorbate concentrations
in the liquid were sampled with time and analyzed by electron
capture detector gas chromatography. Sorption was found to be a two
stage process characterized by a rapid initial uptake followed by a
extended...
The objectives of this investigation were to determine the effect
of pulverization on the strength, durability and swell characteristics
of a lime stabilized clay soil. Samples were prepared with three different
gradations which represented the pulverization of the soil.
Maximum clay lump sizes of 3/4", 1/2" and passing #4 sieve...
A study to determine the effect of certain synthetic organic
insecticides on the Biochemical Oxygen Demand (BOD) Test was
performed. BOD tests on a standard glucose-glutamic acid substrate
were conducted while in the presence of dieldrin, dichlorodiphenyltrichloroethane
(DDT), or diazinon. From the BOD data, the following
parameters were obtained:
1....
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...
A laboratory investigation was undertaken to evaluate the effect
of lateral spacing and lateral diameter on the flow characteristics of
a three dimensional blowing manifold.
The model used in the experimental work was constructed of
clear cast acrylic pipe, five inches in diameter. Laterals of two and
four inch diameter,...
This study considered collision data for Seattle, Washington and Portland, Oregon
in order to determine whether or not red light cameras are effective in reducing red light
running collisions. Red light running is extremely dangerous and is a leading cause of
urban automobile collisions in the United States. Red light...
Concrete is the most widely used construction material in the world. When constructing large concrete structures, concrete may have to be placed in multiple lifts. In these cases, fresh concrete is placed on hardened concrete. The interface that is formed between these two lifts of concrete is known as a...
In recent years, tsunami events have caused great devastation and loss of life around the globe. The coast of Oregon is highly vulnerable to a nearfield tsunami event caused by a Cascadia Subduction Zone earthquake, yet lacks a clear plan for evacuation and disaster mitigation. Vertical evacuation is a proposed...
This work furthers the understanding of processes occurring in catchments that affect stream nitrate concentrations using two different approaches: a temporally intensive case study of three headwater catchments with varying land use (through storm event monitoring) and a spatially intensive study on the regional scale (through statistical modeling) of 1st-4th...
Key parts of the lateral force resisting system in wood-frame buildings
are the shearwafls and the connections. The connections in wooden buildings
are the primary source of ductility and energy dissipation; these are essential
properties when buildings are exposed to lateral forces, such as wind and
earthquakes. Shearwall design is...
Measuring resistivity as a method to calculate formation factor is becoming a popular way to evaluate transport properties of concrete. Resistivity measurements are dependent on multiple factors including the resistivity of the pore solution, leaching effects, the degree of saturation of the specimen, the age of the specimen (degree of...
Many hazardous locations exist on our local and street highway
systems. Such hazards contribute to the frequency and severity of
traffic accidents. The elimination and mitigation of the hazards
reduces accident frequency and severity, as measured by the number of
fatalities, injuries and property damage resulting from the accidents.
The...
Interest in performance specifications has been growing in the civil and construction industry in the past decade. One major focus area has been on understanding how to prolong the service life of concrete structures, since repair and rehabilitation of existing infrastructure have cost many trillions of dollars. Deterioration mechanisms such...
A right-hook crash is a bicycle-motor vehicle crash between a right-turning motor vehicle and an adjacent through-moving bicycle. This study focuses on right-hook crashes that occur during the latter stage of the circular green indication at signalized intersections with shared right-turn and through lanes. The overall objective was to evaluate...
A post-failure investigation of a highway embankment constructed
over organic and sensitive subsoils was made with a series
of field vane tests. The results indicated that the embankment was
quite stable, and, therefore, the reliabilities of both the Φ = 0 slip-circle analysis and the field vane results seemed to...
This thesis evaluates pre-construction auditing procedures used in the United Kingdom, Australia, and New Zealand in order to help create post-construction auditing procedures for the state of Oregon. It was funded as part of the development of the Oregon Department of Transportation (ODOT) Safety Investigation Manual, and also evaluates content...
A mathematical model was developed using
finite difference numerical techniques to examine the
effects of kinetic parameters on the fate of
hydrophobic organic compounds in soil systems. The
model included advection; dispersion; bacterial
metabolism; and sorption and desorption to soil solids
and bacteria, and degradation by bacteria. The most
important...
One of the major items in any program of municipal sanitation is the double problem of water supply and waste water disposal. Since streams are the general source of water supply and also the final receptacle for sewage, this dual use of the stream often leads to complications. Sewage and...
This thesis focuses on the fundamental behavior of CLT floor-to-wall connections during a fire.
Cross-laminated timber (CLT) panelized structures rely on floor-to-wall connections for the load path and stability of the structure. Additionally, the fire performance of these connections is critical to prevent horizontal or vertical fire spread within these...
Timber-concrete composite (TCC) floors have improved strength and stiffness when compared to timber-only floors, allowing for longer spans in buildings and improved life safety. However, North America does not have codes and standards that recognize TCC floors, particularly the improved life safety performance of these floors in fire. Therefore, alternate...
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...
While the use of powered mobility devices for young children with mobility challenges has taken off in recent years following evidence that the use of powered mobility at a young age augments other traditional mobility skill interventions, the research is still limited and focuses on physical impacts more. Recently, the...
In the construction industry, people seek to deliver a successful project. The major success performance measurements in the construction industry are cost, time, and quality. Several researchers have determined critical success factors for construction projects, and one of these critical success factors was management actions. Furthermore, there is an inadequacy...
The life cycle assessment (LCA) process is a systematic approach to determining the environmental impacts of different products and processes. LCA is a relative approach that requires functional equivalence for the results to be compared. A method is presented that achieves functional equivalence by equating the reliability indexes being compared....
In a homogenous and isotropic material, the location of the neutral axis coincides with the location of the centroid of the beam. Wood is anisotropic, meaning that it has different properties in different directions. It is also non-homogenous, meaning that the beam exhibits different properties at different locations throughout its...
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...
Considering the deadly impacts of commercial motor vehicle (CMV) crashes on road safety, many previous studies have put in efforts to find the determinants of CMV crash injury severities. However, studies examining the impact of the different number of lanes on CMV crash
injury severities are lacking. Besides, the importance...
The research examines the effect of restricted head and neck movement on
driving performance as measured by decision time at T-intersections. The traffic
safety and human factors literature was reviewed, and very little was found
concerning drivers with physical limitations. T-intersections were selected for
study because most accidents involving drivers...
The overall goal of this study is to evaluate the earthquake performance of wood frame
shear walls, and more specifically: (1) to compare the performance differences of fully and
partially anchored walls under monotonic, cyclic, and earthquake loads, (2) to compare wall
performance under earthquake loads with that of standardized...
Recent studies have shown that there is a significant amount of dissatisfaction and
stress associated with finances, job security, and work. There are many health related
consequences that manifest in response to this continual stress that we experience in
our professional lives. These include obesity, high blood pressure, high cholesterol,...
The pozzolanic reactivity test (PRT) is used to quantify the pozzolanic reactivity of supplementary cementitious materials (SCMs). The PRT computes reactivity by measuring heat release (Q) and calcium hydroxide (CH) consumption, as interpreted using thermodynamic modeling. The robustness of PRT is examined by experimentally varying CH-to-SCM ratio, solution-to-solid ratio, sulfate...
The present status of plastics is one of constant change, but
this thesis attempts to focus attention on the state of the industry as of
1967. Beginning with a brief title definition and history of plastics,
the writer proceeds to a discussion on the structural characteristics
of plastics. Under this...
As the traffic demand increases at a faster rate than the upgrade and maintenance of
transportation facilities through the traditional public financing methods in the United
States, the Public-Private Partnership (PPP) is becoming an important supplement to
the public transportation infrastructure investment. There are already several existing
PPP toll road...
The use of fly ash as a supplementary cementitious material (SCM) has increased in the last century due to its various environmental benefits as a recycled product. Within the last 60 years, it has been found that it can be used to effectively control damage induced by Alkali-Silica Reaction. However,...
This dissertation presents the results of a research effort conducted to better understand the seismic performance and analysis of pile-supported wharves. Given the limited number of well-documented field case histories, the seismic performance of pile-supported wharves has been poorly quantified, and the analysis methods commonly employed in engineering practice have...
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...
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...