While there have been several efforts to understand large-truck crashes, the relationship between crash factors, crash severity and collision type is not clearly understood. Past studies have utilized different statistical or econometric models to predict the manner of collision at intersections, yet not much attention has been paid to the...
This paper examines the environmental factors influencing
the die-off and transport of fecal coliform bacteria
present in wastes applied to the land surface. These factors
are examined specifically for dairy waste management systems
and the net effect each system has on runoff water quality.
A model is developed that considers...
Dilemma zones on the approach to high-speed signalized intersections have been identified as a safety problem that can contribute to rear–end and right–angle crashes. However, in situations when a pair of vehicles is caught in the dilemma zone, it is not well understood how the following vehicle’s headway and classification...
The concept of construction industrialization, first raised in the 1960s, refers to the transfer of on-site construction work to an off-site factory to improve quality and reduce cost, time, and safety issues. In some countries, industrialization of construction projects is highly recommended and promoted by governments and local construction institutions...
Aligning Real-Time Networks (RTNs) with the National Spatial Reference System (NSRS) is crucial to ensure accuracy, consistency, interoperability, and long-term data integrity for geospatial applications. However, the effectiveness of different alignment methods as well as the need for monitoring approaches to maintain alignment consistency with the NSRS have not yet...
Isolated approaches at signalized intersections with posted speed limits of 45 mph or greater generally experience large numbers of rear-end and angle collisions. A combination of less attentive drivers, high operating speeds, and less than ideal intersection characteristics can result in crash frequencies well above expected rates. A number of...
Mass timber has been considered as a promising building material because of its structural rigidity, environmental sustainability, and renewability nature. In Europe and Australia, mass timber materials have been used for many different types of construction such as residential, commercial, education, and industrial. However, the construction practitioners in the U.S....
Over the decades, worker performance on construction projects has been a significant source of concern to be evaluated. Comprehensive studies have developed models for evaluating worker performance outside of the construction industry; however, minimal research has been conducted to evaluate worker performance in the construction industry. One of the reasons...
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...
Earthquake-induced liquefaction is a large contributor to damage observed following seismic events. Commonly observed damage consists of significant ground and structural failure due to the deformation of large volumes of soil due to soil liquefaction and lateral spreading. A significant focus of geotechnical seismic research concentrates on the development and...
Signalized intersections often provide pushbuttons to call for pedestrian service to minimize conflicting movements between road users. Signalized midblock crossings typically increase safety for pedestrians in locations with high traffic volumes and multiple lanes in each direction. However, unnecessary vehicular delay occurs from “ghost” pedestrian intervals when someone activates the...
Design methods for pavement mixtures containing recycled asphalt
concrete have been explored in many studies. Most methods of design
are modelled after procedures originally developed for conventional
construction with virgin raw materials. The unique properties of aged
asphalt as raw material are rarely considered when applying conventional
procedures. The approach...
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...
The number of international inbound tourists to the United States has risen steadily. To serve these and other tourists best, traffic signs need to communicate information correctly across a potential language barrier. Of particular interest is the traffic sign intended to communicate directions to Tourist Information centers. While the general...
Significant use of cold in-place recycling (CIR) has occurred in
Oregon since 1984 as an alternative to other rehabilitation techniques
or to the reconstruction of distressed asphalt concrete (AC) pavements.
Due to the initial success of the projects cold recycled during 1984-85,
the Oregon Department of Transportation (ODOT) and Oregon...
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...
Travel demand has increased due to population growth, increase of vehicle ownership, and development patterns resulting in greater levels of congestion, pollution, and crash frequency. One approach to demand management is to increase the share of trips made by bicycles. With the increase in bicycling rates, there is a critical...
Students in undergraduate engineering programs typically do not synthesize content learned from disparate course work until the end of their final terms of college. As an example, in undergraduate civil engineering programs, transportation engineering concepts (e.g., geometric alignment, asphalt design procedures) and geotechnical engineering concepts (e.g., shear strength of soils,...
Accommodating motor vehicles that are turning (left or right) at signalized intersections requires a careful understanding of the safety and efficiency of design and operational variables. Turning vehicles are the primary collision risk for non-motorized road users at signalized intersections. When turning movements need to be controlled, proper driver response...
Intersections pose unique transportation challenges regarding safety and operational efficiency. When pedestrians currently want to cross at intersection, they need to use a push button to issue a call for service. The call is static and cannot be altered or changed. But by implementing dynamic passive pedestrian detection sensors, intersections...
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...
Side-scan sonar records in Oregon's Coos Bay estuary navigation
channels were obtained at intervals of two to three months during the
November 1974 - October 1975 time period from Coos Bay Channel Mile
11+50 to 15+20, and from a reach in the Marshfield Channel. A limited
side-scan survey effort was...
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...
A literature review and a computer study are conducted to identify
the requirements of finite element programs for the specific use of discrete
analyses of reinforced soil structures. The utility of six commercially
available programs are appraised with respect to the identified
requirements. The results of the study are directed...
The role of ground motion duration on the seismic performance of civil engineering structures remains unclear. Thus, the role of earthquake strong ground motion duration is assessed in a three manuscript thesis, which includes: (1) assessment of the effects of ground motion duration on the seismic performance of a model...
Urban stormwater runoff with a high impervious area can significantly impact pollution concentrations of receiving water bodies. The use of low impact development (LID), which mimics the hydrological properties of the site before development, has been studied in an increasing number of studies, and the available database has shown to...
Rubber-modified asphalt pavements have been used in Sweden and the United States since the 1970's. In these applications ground recycled tire particles (0.25 inch minus) are added to a gap-graded aggregate and then mixed with hot asphalt cement. The benefits of adding rubber to the mix include increased skid resistance...
Ocean waves propagating over cohesionless seabed deposits
produce cyclic shear stresses within the deposit. Under certain
conditions these stresses may cause a progressive build-up of pore
pressure. Pore pressure accumulation can result in liquefaction or
a substantial decrease in the effective stress with attendant large
deformations of the seabed deposit....
CSS-1H is the most commonly used slow-setting emulsion grade in Oregon. “New” engineered emulsions were recently developed in Oregon to reduce tracking, the pick-up of tack coats by construction vehicle tires during construction activities, and increase interlayer shear strength (ISS), the amount of adhesive bond present between layers of asphalt...
Polymer modified asphalts have recently been the focus of much
attention in the U.S. due to claims that polymer additives will
lengthen the life of an asphalt pavement. Much of the published
research on this topic has been concentrated on the effects of
polymer modifiers on binder and mixture properties....
The objective of this project was to evaluate methods to remediate a wood I-joist with a single, circular hole in the web while leaving utilities in place. The methods were experimentally evaluated with a full-scale bending test using four equally spaced point loads. There were three depths of joists with...
In this thesis, the effectiveness of the 100 percent + XX percent seismic response directional combination rule available in codes and standards is evaluated using simulated nonlinear seismic response of two existing multi-story reinforced concrete plan-irregular buildings. The 5-story and 8-story buildings were designed according to the 1975 seismic codes...
Coastal Oregon is deficient in quality construction aggregate.
There is, however, an abundance of lower quality, or marginal aggregate
available for construction purposes. The purpose of this report
is to develop techniques for upgrading marginal aggregates with portland
cement and methods for evaluating the relative performance of
these stabilized materials...
It is considered best practice when designing pedestrian access at intersections to provide two curb ramps at each street corner. In Oregon, there are many locations where long ramp runs cause curb ramps to be set back a significant distance from the apex of the intersection corner to meet this...
Physical modelling is instrumental to the progression of coastal engineering research and our understanding of the offshore and nearshore environments. Scaled models are designed and built to be tested in coastal research laboratories, where a wave basin or flume generates the desired wave conditions for experimentation. The surrounding hydrodynamics of...
Straw wattles are common erosion control devices used to trap sediment. This
thesis studies the relationship of straw wattles on slope stability through a case study
demonstrating their use on steep slopes (1.5H:1V) for the US20 highway realignment
project. Several surficial slope failures have occurred on these fill slopes, often...
The objective of this project was to develop an analytical model of a light-framed wood structure using a prevalent structural analysis computer program in order to evaluate system effects and define load paths within the structure, especially under extreme wind events. Simplified modeling techniques and material definitions were developed and...
Performing bridge inspections can be a very daunting task for every department of transportation (DOT) in the country. Because the leading cause of deterioration in reinforced concrete bridge decks is corrosion of the steel reinforcement, the ability to detect the concentration of corrosion-causing chlorides in the concrete, using a non-destructive...
The most common test methods to evaluate alkali-silica reaction (ASR), the concrete prism test (CPT) and the accelerated mortar bar tests (AMBT), have limitations and are not entirely reliable in terms of predicting the performance of concrete with prevention measures under field conditions. In this study, the miniature concrete prism...
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...
Lateral spread is a pervasive type of liquefaction-induced ground failure that occurs on gentle slopes or near free-faces, such as river channels. Resulting horizontal displacements can reach up to several meters, and can be considerably damaging to foundations, bridges, roadways, pipelines, etc. In the 1990s, Bartlett and Youd (1992a, 1995)...
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...
Shallow landslides are a prevalent concern in mountainous regions that can result in severe societal, economic, and environmental impacts. The challenge is further compounded as the size and location of a potential slide is often unknown. This study presents a generalized approach for the evaluation of shallow landslide susceptibility using...
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...
There are about 80 million single-family dwellings (SFD) in the United States, predominantly of wood-frame construction. Of these, 68% are owner occupied. A home is typically the largest single investment of a family, and is often not covered by earthquake insurance, even where it is available. Of all SFD in...
The onset of the COVID-19 pandemic led to significant transformations in global mobility patterns, primarily driven by stay-at-home orders and economic shutdowns. These measures resulted in a substantial decline in travel activities worldwide. In the United States, there was a notable reduction in travel demand, with a corresponding decrease in...
With rising sea levels and more frequent exposure to extreme storms, coastlines worldwide are vulnerable to increased erosion and loss of natural marsh lands. In an effort to lessen these impacts, there is a growing practice of adapting hard or “gray” coastline protection techniques to more nature-based features that promote...
Many conventionally reinforced concrete deck girder (RCDG) bridges were built in the US during the 1950s, throughout the expansion of the Interstate System. Designs followed the AASHO standard of the time, which permitted higher shear stress in concrete and reduced detailing requirements than permitted by current specifications. Many of these...
Ponding of water on roof systems leading to collapse causes expensive damage and jeopardizes the life safety of building occupants. Current building codes and design specifications for flat roof systems offer minimal guidance in designing for ponding loads. The present research investigated ponding load effects on a long span, lightweight...
Pile caps are structural elements used to transfer loads from columns to a group of piles, which transfer them to stronger soil layers. Pile cap with horizontal distance between the column and piles less than twice its effective depth is categorized as "deep," where significant nonlinear strain distribution occurs through...
Coastal vegetation dampens waves which can provide benefits to the local area, but existing literature shows large variations in the degree of wave height attenuation depending on plant properties and wave conditions. Better knowledge of how to predict the wave height decay accurately in different types of vegetation may help...
Two built-up wide-flange beams with several large holes in each
beam were tested to failure. Strains were measured by strain gages
at various levels, located at the ends and center of typical holes, and
deflections were measured optically at two points on each beam.
Lateral bracing was provided to prevent...
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...
Chromium and its compounds are widely used by modern industries, resulting in large quantities of this element being discharged into the environment. To remove chromium from contaminated soils and ground water, it is necessary to predict chemical and physical processes that control the rate of reactions and transport of chromium...
The effects of steel reinforcement, chloride-induced corrosion initiation, cracking and delamination on the electrical resistivity measurements using the Wenner probe technique were studied experimentally on custom-designed reinforced concrete slabs. Investigation parameters included (1) probe configurations with respect to rebar mesh, (2) rebar density, (3) epoxy coating on the rebar, (4)...
The collapse of the I-35W Bridge in Minneapolis, MN on August 1, 2007 brought into question the design and inspection of gusset plates in steel truss bridges. The experimental tests performed in this research study the sway-buckling strength and behavior of large-scale steel gusset plates in an isolated truss connection....
Fabricated steel beam specimens with rectangular holes cut in
the webs were subjected to load tests to analyze the behavior of the
modified section. Beam-depth to hole-depth ratio was in all cases
2.0; however, ratio of hole length to hole height varied from 2.0 to
3.0. The primary instrumentation of...
To better understand the extreme local amplification of tsunami, the experimental investigation on counter-propagating solitary wave collisions over a horizontal bottom was conducted using the optical measurement techniques: Particle Image Velocimetry (PIV), and Laser Induced Fluoresce (LIF). Head-on collisions and oblique collisions of equal-amplitude as well as unequal-amplitude waves were...
The behavior of mass timber beam-to-column connections under seismic loading is not yet well understood. Mass timber beam-to-column connections must have the ability to maintain load-carrying capacity despite the deformations that will be imposed on all components of the building during seismic events. This behavior is called deformation compatibility. The...
Short non-flexible elements of cable were driven harmonically
in water while constrained by springs. The cable elements were observed
to oscillate at approximately the Strouhal vortex shedding
frequency. Damped resonance occurred near the point where the natural
frequency and the Strouhal vertex shedding frequency were equal.
Transverse oscillation amplitudes greater...
Preparing successful engineering undergraduate students for the workforce is imperative and requires students to apply their conceptual understanding of engineering fundamentals to engineering design work. Conceptual understanding is assessed through the use of concept inventories. Learning theories may help explain differences in concept inventory performance. Expert novice theory suggests that...
Transportation agencies need efficient methods to determine how to improve bicycle facilities in order to improve connectivity and safety. Many studies have used standalone methods such as level of traffic stress (LTS) and bicycle level of service (BLOS) to better understand bicycle mode share and network connectivity for a region...
Wave runup is an important physical process that affects nearshore sediment transport, coastal erosion, and flooding. Large and unexpected runup events can also be dangerous to beach goers. Extreme runup statistics are essential parameters used in engineering design of marine structures and in coastal management. Although the study of runup...
Nonlinear large deflection finite element analyses of a fabric
reinforced embankment on muskeg were performed to predict fabric
tension and the effect of fabric stiffness on embankment deflections.
The predicted fabric tensions were compared with the results of a
sliding block analysis, and show this simple analysis requires further
correlation...
The roles of fabrics in subdrains are identified for normal
groundwater flow conditions to determine hydraulic and pore characteristics
necessary for design considerations. Two conditions are discussed:
(1) the fabric in direct contact with the soil to provide
mechanical support, and (2) the fabric as a filter to remove soil...
This thesis explores the factors limiting the alkene substrate range of the vinyl chloride (VC)-utilizing bacteria, and describes a method for measuring VC transformation in situ. Vinyl fluoride (VF) was evaluated as a surrogate for monitoring aerobic VC-transformation utilizing three isolates, Mycobacterium EE13a, Mycobacterium JS60 and Nocardioides JS614. JS614 grew...
There is renewed interest in North America for the use of calcium aluminate cement (CAC) in infrastructure repair. The interest is driven by the specialty properties that make CAC the ideal candidate for particular applications. These include rapid strength gain, even at temperatures approaching 0°C, the ability to customize fresh...
Two interesting challenges have been created in the traditional transportation planning process through recent adoption of more interactive roles by Federal, State and local transportation agencies and of those representing the communities being impacted by proposed transportation projects. First, the decision-making groups that formerly included solely transportation and related professionals...
A conceptual model was developed to further the understanding
of the evolution and fate of volatilized ammonia in
the atmosphere. Recent trends in livestock rearing have
been toward confinement facilities in which high animal concentrations
are maintained. One of the impacts of these
facilities has been increased local concentrations of...
Use of basalt aquifers for aquifer storage and recovery (ASR) systems is increasing in the Pacific Northwest due to the large aerial extent of the Columbia River Basalt Group and the suitability of basalts as ASR reservoirs. However, the degradation of trihalomethanes (THMs), potentially carcinogenic disinfection by-products present in the...
With ever-increasing number of vehicles actively using the state and national roadway network, transportation-related fuel consumption and consequent pavement structural damage rises. In this dissertation, the impact of material-induced dissipated energy mechanisms in asphalt and concrete pavements were analyzed using field measurements in California and finite element modeling of pavement...
Dredged spoil plumes are monitored during nine hopper dredge
disposal events in 186 foot water depths offshore near Coos Bay,
Oregon. Position and solids volume concentration characteristics of
the plumes are established.
Computer simulations of the monitored events are executed using
the WES modified version of the Koh-Chang instantaneous disposal...
For centuries wood has served as a primary structural building material in small
dwelling, large communal structures, bridges, and temporary structures. Even
today wood is the dominant material in residential construction. Despite this long
standing use of wood, non-residential multi-story construction in light of the green
building revolution has yet...
Problems associated with quantification of deep water wave kinematics
and dynamics are examined. Summaries of Stokes' theory and Dean's
stream function theory are reported. A computer algorithm is developed
to solve the hydrodynamic characteristics for Stokes' fifth and third
order and linear theories. Tests are initiated to verify the results...
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...
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...
The time-domain simulation of wave-structure
interactions using the finite element method is presented
in this study. Combined initial and boundary value
problems for diffraction and radiation of waves by large
structures are posed. Linearized free surface boundary
conditions are used, but motions of the structural
boundaries compared to the wave...
The collapse of the I-35W Bridge in Minneapolis, MN in 2007 prompted an investigation into the design and inspection of the steel truss bridges. Further investigation into the collapse revealed that a gusset plate experienced sway buckling, causing the bridge failure. This bridge failure motivated research into the analysis and...
Three-dimensional finite element models are developed to simulate the behavior of four fill-scale reinforced concrete beams. The beams are constructed with different fiber-reinforced polymer (FRP) strengthening schemes, and are modeled using ANSYS, a commercially available finite element analysis program. The experimental beams replicate the transverse beams of the Horsetail Creek...
In recent years confinement requirements for concrete columns have increased in seismic regions. Steel jackets are one way to confine reinforced concrete columns. The increased confinement provides additional strength and ductility for the columns during seismic events. For reinforced concrete columns with steel jackets, there are different section properties in...
For mid-rise and high rise buildings, slender reinforced concrete (RC) structural walls are commonly used as the main structural elements to resist lateral applied loads in high seismically areas around the globe. These RC structural walls can provide substantial deformation capacity, stiffness, and lateral strength through the contribution of their...
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...
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...
Large numbers of reinforced concrete deck girder (RCDG) bridges were built during the highway infrastructure boom of the 1950's. The advent of standardized deformed steel reinforcing bars during this time allowed for straight bar terminations in flexural tension regions. Designers of the time terminated reinforcing bars where they were no...
Large numbers of reinforced concrete deck girder bridges that were constructed during the
interstate system expansion of the 1950s have developed diagonal cracking in the stems.
Compared to the present AASHTO-LRFD standards, the provisions of the 1950s allowed
for higher shear stress in the concrete, thus reducing the amount of...
This paper examines the response of submerged model sand
slopes to vibration and the beneficial effects of placing rock revetments
on the face of the slope to prevent flaw slides.
Pore water pressure response and deflection were used as a
criteria for stability in an attempt to relate stability with...
While real-time hybrid simulation has been utilized for structures subjected to seismic events for decades, its use in fluid-structure interaction problems is still a novel endeavor. Gathering data for cascading seismic and tsunami events is difficult due to space constraints in existing experimental facilities, complications regarding the application of scaling...
To facilitate the evaluation and design of structures subjected to fluid loading, a study of fluid-structure interaction (FSI) using the particle finite element method (PFEM) is presented to approximate the responses and sensitivities of structures which interact with fluid. A wide range of structural types are permissible by making no...
Because of the organic nature and the natural foaming characteristics
of kraft mill effluents, it was decided to investigate the
feasibility of using foam separation as a method of treatment. The
treatment efficiency was evaluated by BOD and COD reductions as
well as the decrease in toxicity to marine life....
An experimental study was conducted to determine the hydrodynamic
forces on smooth and roughened circular cylinders as
influenced by a nearby plane boundary. The ambient flow was perpendicular
to the cylinder and parallel to the boundary. Measurements
were taken in a water channel and a wind tunnel to obtain the...
The fractal dimension of measured ocean wave profiles is found to be in the range of 1.5-1.8. This non-integer dimension indicates the fractal nature of the waves. Standard formulations to analyze waves are based on a differential approach. Since fractals are non-differentiable, this formulation fails for waves with fractal characteristics....
In the field of construction safety, many researchers have worked to create assessment tools. These tools focus on different aspects of construction safety, such as assessing safety climate, safety culture, etc. Although research indicates that the majority of incidents are caused by unsafe behaviors and acts, there are no comprehensive...
Over the years, the performance of construction projects has been a main source of concern given the percentage of a project cost associated with poor project performance. As a result of the growing clamor to improve the output of the built industry, comprehensive studies have been conducted to examine the...