A generalized, three-dimensional, finite element bridge model was created in order to efficiently and accurately assess live-load girder distribution factors for a variety of bridge types. This model shortens the time required by bridge analysts to develop individual finite element models for bridges of varying geometries. The creation of the...
Fire hazards threaten human life and property safety. Since it is unrealistic to study human behavior during a real fire hazard, computational tools are a better choice to computational tools are a better choice to simulate fire growth and human behavior for predicting evacuation performance in chaotic emergency situations. Although...
An investigation was made to test the method of Head on the
flow about a circular cylinder with suction. The method of Head is an
approximate method of obtaining solutions to the boundary layer equations.
The method was adapted to the digital computer to facilitate
performing the calculations, and a...
Chloride-induced corrosion is one of the primary causes of the degradation of reinforced steel in concrete structures. Currently, the rapid chloride permeability test (RCPT) is the most specified method to determine the concrete’s resistivity to chloride ingress, thus a determining factor in assessing the durability of concrete. While it is...
A computer program called SAPWOOD which possesses the
capability of performing linear or nonlinear, static or
dynamic response including seismic excitation for wood-framed
buildings with semirigid connection systems is
presented in this study. Program SAPWOOD is a modification
of the program NONSAP by adding new elements such as a
linkage...
Previous research has shown that using fine lightweight aggregate (FLWA) can be a promising strategy to mitigate alkali-silica reaction (ASR) in mortar and concrete. While several possible theories were proposed by researchers, discrepancies in testing methods, materials, and supporting evidence still exist. Therefore, this study was initiated. There are two...
Predetermining the ultimate capacity of piles driven into purely
cohesive soils and purely cohesionless soils involves, respectively,
the consideration of soil shear strength in a completely undrained and
a completely drained condition. For the intermediate cases concerning
soils that possess both cohesion and internal friction (silts, clayey
silts, sandy clays,...
Liquefaction of saturated granular material due to cyclic loading can result in catastrophic damage to the built environment. The mechanics of liquefaction have been previously studied through field testing, physical modeling, laboratory experiments, and numerical simulations. However, significant questions remain with respect to the particle-scale behavior of granular materials during...
Despite recent efforts to improve site safety, construction still accounts for a disproportionate injury and illness rate. According to the 2007 injury and illness data released by the National Safety Council, the construction industry has a fatality and disabling injury rate that is approximately three times higher than the all-industry...
Debris generated after a disaster event must be disposed efficiently for community recovery. This is a significant operation that accounts for up to 27% of the total recovery costs. Generally, debris removal takes place in two phases: the short-term relief phase, which involves debris removal immediately after a disaster to...
Aggregate piers have been used for centuries, with increasing occurrence in the last few decades. Their usage has been driven by land development demand and enabled through equipment and engineering improvements. Understanding the principles controlling bearing capacities and serviceability performance has been an ongoing area of interest for structures supported...
A Langmuir sorption model incorporating a second step of
irreversible absorption was applied to a model soil system. The column
was packed with cellulose triacetate; pulse and step input tests with
3,4-dichlorophenol were performed; the effluent concentration was
measured by electron capture detector gas chromatography and sorption
rate constants were...
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...
The results of three hydraulic model tests to evaluate the stability
of a placed stone breakwater are presented and discussed. The prototype
breakwater was designed to protect offshore power and port facilities in
60 feet of water and was tested at scale ratios of 1:10, 1:20, and 1:100.
The armor...
With current nonlinear analysis computer capabilities, this
study was conducted to develop a linkage element that permits
analyses of wood composite structures taking into account possible
slip in the nailed joints. The finite elements chosen to represent the wood stud, plywood, gypsum and nails are described. The
method as applied...
Plate loading tests in rock are deceptively simple tests to perform.
Consequently, many varieties have been developed in the past
60 years. From each of the varieties various investigators have added
their own developments and modifications, some good, and some not so
good. The result has been a confusion of...
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...
The development of a pavement management system for low-volume roads is a difficult task. There are many interrelated activities that must be considered, such as planning, design, construction, maintenance, and pavement evaluation. This paper addresses the evaluation and maintenance components of a pavement management system for low-volume roadways and provides...
The biodegradation of five polychlorinated biphenyls (PCBs) by
Hudson River and Silver Lake sediments was studied using gas
chromatography with electron capture detection (GC/ECD) and gas
chromatography with mass spectrometry (GC/MS) analyses. Methanogenic
sediments from the Hudson River and Silver Lake were used to inoculate
four anaerobic filter reactors. The...
The effects of vertical ground motion are particularly significant
in the design of highway bridge girders. Conventional codes do
not recommend methods for solving the problem. The intent of this
work is to suggest an approach for such design.
A set of curves for velocity spectra which are the average...
As mass-timber building construction rises around the globe, there exists the need to verify the long-term, in-situ behavior and performance of these structural systems. Structural health monitoring (SHM), generally defined as a damage detection strategy consisting of a network of sensors, a data acquisition system, and algorithms for data analysis,...
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 spreadsheet-based transport model was developed in Microsoft Excel™ as part of a six-year National Cooperative Highway Research Program project conducted at Oregon State University. The model simulated the leaching, transport, removal, and retardation processes that occur in the surface and subsurface pathways of the near highway environment. For all...
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...
The concept of placing high strength linear reinforcements in a
soil backfill to produce a vertical retaining structure is a recent idea
that has been applied with success at a number of locations. Rational
procedures have been developed for the design of these structures
when the reinforcements consist of long...
Unmanned aircraft systems (UAS), also known as drones, are an increasingly popular method of collecting surveying and mapping data. Two common drone-based mapping techniques are lidar and structure from motion (SfM) photogrammetry, and a frequently-heard (yet nearly impossible to answer) question is: “which is better?” The most common metric for...
Bio-cementation is a promising method for the liquefiable mitigation of loose saturated sands. In the improvement process a bacterium that can be found naturally in soil deposits is fed urea. The bacterium consumes and breaks down the urea to form ammonium and carbonate. In the presence of calcium, calcium carbonate...
This thesis presents a novel approach for propagation of uncertainty in river systems. Errors in data observations and predictions (e.g., stream inflows), in model parameters, and resulting from the discretization of continuous systems, all point to the need to accurately quantify the amount of uncertainty carried through the modeling process....
Salt-encrusted flats, or Sabkha, are common in arid and semi-arid regions worldwide, including coastal and inland areas. Due to their low shear strength and high compressibility, these soils are often unsuitable for supporting infrastructure or structures. The unique salt content of sabkha formations sets them apart from other soil types....
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...
In this study, a coupled potential flow-viscous flow model is used for numerical wave tank simulation. The solver satisfies all the requirements for such a simulation environment. The coupling scheme is based on a non-overlapping heterogeneous domain decomposition method. In this method, the flow domain consists of two subdomains. In...
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...
Metal-plate-connected (MPC) trusses have traditionally been designed based on a
tributary load distribution and a simplified truss model. This design method ignores the
load-sharing and composite action in MPC roof truss systems, the semi-rigidity of MPC
joints, and joint eccentricity.
The main objective of this study was to provide a...
This study presents a practical method to model an actual Metal-Plate-
Connected (MPC) roof truss assembly using a commercial program, SAP2000, to
investigate its system performance. Truss assembly modeling was examined
because the conventional single truss design method ignores system effects, such as
variability of modulus of elasticity (MOE), interaction...
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...
In recent decades, the occurrence of large, high severity wildfires has increased substantially in many parts of the world, including the western United States. These fires have the potential to impact water quality, aquatic ecosystems, and downstream communities for many decades. As such, it is increasingly important to understand the...
This thesis presents a procedure to identify and evaluate forest
arterial and collector networks. The procedure identifies those
decision criteria important in evaluating both the arterial and
collector networks and the specific facilities identified on these
networks. The procedure incorporates the decision criteria and results
from network and facility analysis...
Shallow landslides are destructive natural hazards that result in widespread losses, both of infrastructure and lives, throughout the world. To help mitigate the impact of landslide hazards, they are commonly characterized across a regional scale by (1) their location and likelihood using susceptibility maps, (2) their magnitude and frequency using...
This thesis presents an analytical, experimental and numerical study of the initiation of flows in a siphon for rapid and gradual openings of a downstream valve. Three initial water levels in the upstream tank and four final positions for the downstream valve were investigated. Two opening times of the downstream...
State Departments of Transportation (DOTs) are the primary owners of roadway infrastructure in the United States. Many of the employees of state DOTs work on roadway work sites, putting them at disproportionately higher risks of injury or fatality. A review of the literature determined that a combination of policies, standards,...
Resistance of reinforced concrete beams to diagonal tension
was studied in a series of papers which included beams without
web reinforcement and beams with various types of web reinforcement.
The magnitude of the loading causing the formation of initial
diagonal tension cracks depended primarily on the dimensions of
the cross...
The Manual on Uniform Traffic Control Devices prohibits positioning a bike lane right-adjacent to a vehicle turn-only lane to mitigate the potential for right-hook crashes. However, it provides no specific guidance on positioning with respect to bus-only lanes. This thesis describes a before/after safety evaluation of bike lanes positioned left...
Characterizing stakeholder behavior when making decisions in watershed management is a great challenge for planners, not only because plans are associated with physical uncertainties but also because stakeholders’ behaviors are influenced by numerous factors. Since stakeholders’ decision-making is linked to multiple types of uncertainty, communication of uncertainty to stakeholders by...
Improving safety education could contribute to the preparation of better professional engineers. Safety topics are not holistically embedded in transportation course curricula. This thesis explores the current state in which safety is being incorporated in transportation course curricula in terms of design and compares the uses of safety data in...
Mathematical models of the precipitation process are needed to
effectively use historical precipitation data in the design and
planning of engineering projects and for analysis of watershed
runoff behavior. Existing simple models based on the assumptions of
independent, identically-distributed random variables are
insufficient to describe several features of the historical...