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Full-Text Articles in Engineering

Determinant Factors Of Bicyclist Injury Severity At Signalized And Unsignalized Intersections, Apy Das Nov 2021

Determinant Factors Of Bicyclist Injury Severity At Signalized And Unsignalized Intersections, Apy Das

Dissertations and Theses

Bicycling is becoming increasingly popular in Oregon and the US in general due to its environment friendliness as well as health benefits. With Oregon's population projected to increase by more than 30% over the next 30 years, improving the safety of the transportation network for persons on bicycles is important. In Oregon, majority of the bicyclist crashes occur at intersections. This thesis seeks to identify the determinant factors that significantly impact bicyclist crash injury severity at intersections. A mixed logit framework that accounts for any unobserved heterogeneity in the data and allows the estimated parameters to randomly vary across observations …


Improving Bicycle Crossings At Unsignalized Intersections Through Pavement Markings: Analysis Of The City Of Portland Innovative Strategy, Frank Boateng Appiah Sep 2021

Improving Bicycle Crossings At Unsignalized Intersections Through Pavement Markings: Analysis Of The City Of Portland Innovative Strategy, Frank Boateng Appiah

Dissertations and Theses

The increasing trend in the number of bicycle crashes in the U.S since 2009 has been a major challenge to safety. In 2019, a total of 36,096 people were killed on U.S roadways. A total of 846 (2.3%) of these fatalities were bicyclists and around 75% of the bicycle fatalities occur in urban areas and intersections are common locations of crashes. Many bicycle enhancements such as bike boxes, bicycle signals, curb extensions have been installed to improve safety at signalized intersections. The City of Portland OR experimented with an innovative treatment to improve bicycle crossings at unsignalized crossings. This treatment, …


Undrained Cyclic Loading Of Low Plasticity Silty Soils In The Pacific Northwest Using Laboratory And Field Cyclic Shear Testing, Angelica Melissa Preciado Reyes Sep 2021

Undrained Cyclic Loading Of Low Plasticity Silty Soils In The Pacific Northwest Using Laboratory And Field Cyclic Shear Testing, Angelica Melissa Preciado Reyes

Dissertations and Theses

The cyclic behavior of a fine-grained low plasticity silty soil (plasticity index of approximately 15) at a site in Portland, Oregon, is characterized using a field and laboratory cyclic shear test program. The field cyclic tests were performed using the NHERI@UTexas large mobile shakers T-Rex and Rattler. The laboratory tests were performed using resonant column torsional shear and cyclic direct simple shear devices. This testing program's results were used to evaluate the soil's potential to develop excess pore water pressure with cyclic shear strains ranging from 0.00001% to 3%. The laboratory cyclic test results are compared against field cyclic test …


Kinematic Demands On Pile-Supported Wharves Due To Liquefaction-Induced Lateral Ground Deformations, Thomas John Torkelson Ii Jul 2021

Kinematic Demands On Pile-Supported Wharves Due To Liquefaction-Induced Lateral Ground Deformations, Thomas John Torkelson Ii

Dissertations and Theses

Kinematic demands from lateral soil deformations can be a major cause of damage to maritime and highway transportation structures such as wharves, ports, and bridges. Data from five centrifuge tests on pile-supported wharves were used to evaluate the accuracy of Newmark Sliding Block Analysis in estimating the kinematic demands on piles. The piles in the centrifuge tests were subjected to varying degrees of liquefaction-induced lateral ground deformations. Pile-pinning effects were included in the analysis by incorporating the lateral pile resistance in the limit-equilibrium slope stability analysis. The results of the analysis have shown that the median Newmark displacements better estimated …


Modeling Cyanotoxin Production, Fate And Transport In Surface Waterbodies, Bernadel Rose Hintz Garstecki Jul 2021

Modeling Cyanotoxin Production, Fate And Transport In Surface Waterbodies, Bernadel Rose Hintz Garstecki

Dissertations and Theses

Cyanobacteria exist throughout the world and are frequently associated with forming toxic blooms. The toxins produced by cyanobacteria, cyanotoxins, are harmful to both humans and animals. Rising temperatures due to global climate change, increased nutrient loading, and other anthropogenic impacts on waterbodies are expected to increase the prevalence of cyanobacteria. It is vital that we protect our drinking water supplies and natural water resources. Modeling the production and movement of these toxins is an important step in limiting exposure to them and evaluating management strategies to mitigate their impact. Cyanotoxins are diverse and the conditions under which they are formed …


Using Quantitative Stereology On High Resolution Sem Images To Estimate Diatom Percentages, Ariadna Covarrubias Ornelas Jul 2021

Using Quantitative Stereology On High Resolution Sem Images To Estimate Diatom Percentages, Ariadna Covarrubias Ornelas

Dissertations and Theses

Diatoms are single-celled organisms of various shapes and sizes typically found in aquatic environments. When diatoms die, the organic material decomposes, and the outer skeletons (i.e., frustules) settle and accumulate as sedimentary deposits. These soils, called diatomaceous soils, exhibit nontraditional behavior since the diatom particles are typically hollow skeletons composed of amorphous silica with intricately patterned and abrasive surfaces. Recent studies have shown that diatomaceous soils are challenging geomaterials since even a small percentage of diatom particles will notably affect engineering behavior. Furthermore, laboratory studies on diatomaceous soil mixtures have demonstrated that many engineering soil properties depend on the percentage …


Field Trials And Long-Term Monitoring Of Microbially-Induced Desaturation For The Treatment Of Liquefiable Silty Soils, Kayla Rae Sorenson Jul 2021

Field Trials And Long-Term Monitoring Of Microbially-Induced Desaturation For The Treatment Of Liquefiable Silty Soils, Kayla Rae Sorenson

Dissertations and Theses

Earthquake liquefaction hazards in silty soils are a critical problem in Portland, Oregon, and other areas around the world. This is a particular problem for existing facilities founded on liquefiable soils, for which there exists no cost-effective liquefaction mitigation solution at the present time. It is essential from both a seismic safety and a seismic resilience perspective to be able to mitigate potentially liquefiable soils underneath existing structures, and to do so in a cost-effective manner. Recent studies suggest that liquefaction mitigation using microbially-induced desaturation (MID) may provide this capability.

The objective of MID is to reduce earthquake-induced excess pore …


Comparing Instruments For Measuring Runoff From Experimental Ecoroof Platforms: A Case Study On Test Plots At Portland State University, Chance F. Hodges Jul 2021

Comparing Instruments For Measuring Runoff From Experimental Ecoroof Platforms: A Case Study On Test Plots At Portland State University, Chance F. Hodges

University Honors Theses

Stormwater management is a primary ecological benefit ecoroofs provide to ecosystems. Quantification of runoff from large scale ecoroofs is difficult to replicate, so researchers often utilize smaller experimental ecoroof platforms. This approach is becoming increasingly common, so it is useful to compare and contrast approaches for runoff measurement at the platform scale. This paper uses the four 17.86 m2 ecoroof platforms located on the Science Research and Teaching Center (SRTC) at Portland State University (PSU) in Portland, OR as a case study. A unique condition of these platforms is that they are installed at grade on the roof with …


Do Secondary Cyclones Increase The Category Scale Of Atmospheric Rivers?, Edgar Sanchez Fausto Jun 2021

Do Secondary Cyclones Increase The Category Scale Of Atmospheric Rivers?, Edgar Sanchez Fausto

University Honors Theses

Atmospheric rivers (ARs) play a crucial role in delivering precipitation worldwide. This makes them an important phenomenon for water resource specialists to study. One such interest is to understand what mechanisms make ARs produce significant rainfall and associated hazards such as flooding. One possible mechanism is that AR duration or intensity may increase when it interacts with a secondary cyclone, either of which can increase the AR category scale. The purpose of this study is to determine whether AR and secondary cyclone interactions increase the category scale ARs. Out of 52 AR events analyzed, 32 events contained at least one …


Incorporating Conditional Ss-Mean Based Equity Metric In Coverage Based Facility Location Problems, Rohan Sirupa Jun 2021

Incorporating Conditional Ss-Mean Based Equity Metric In Coverage Based Facility Location Problems, Rohan Sirupa

Dissertations and Theses

A classical maximum coverage facility location problem (MCLP) tries to maximize the coverage by serving all possible demands within the specified coverage radius. Depending on the applications, several families of MCLP variants have been developed - each with its unique set of additional constraints. One specific application is locating Emergency medical service (EMS) units. EMS units such as ambulances or drones with emergency supplies are located using models such as the maximum expected survival location problem (MEXSLP). However, a classical MEXSLP model tends to locate EMS units near densely populated regions, resulting in increased response times for lowly populated regions. …


Tensile Strength Evaluation Of Glulam Connection With Screw Fasteners, Bradley Sharpshair Jun 2021

Tensile Strength Evaluation Of Glulam Connection With Screw Fasteners, Bradley Sharpshair

Civil and Environmental Engineering Master's Project Reports

Multiple knife plate and external steel plate deep-beam glulam connections were investigated in a series of destructive tests within the Infrastructure Testing and Applied Research laboratory at Portland State University. The goal of these tests was to better understand the failure mode and ultimate load capacity of the large-scale glulam moment connections. Two different types of tests were performed on each connection; one with axial loading, and another loaded in flexure. The first, smaller, axial tests were conducted to inform the later, much larger, bending tests. The results of these tests helped to develop future designs as well as provide …


Development Of A Design Guideline For Pile Foundations Subjected To Liquefaction-Induced Lateral Spreading, Milad Souri May 2021

Development Of A Design Guideline For Pile Foundations Subjected To Liquefaction-Induced Lateral Spreading, Milad Souri

Dissertations and Theses

Extensive loss of stiffness and strength in liquefied soils can cause large ground deformations during strong earthquake shaking. One of the major sources of damage in pile foundations in liquefied soil is the excessive deformation due to lateral spreading. Pile-supported wharves subjected to earthquake motions are expected to accommodate inertial loads imposed at pile head from the superstructure as well as the kinematic loads imposed on piles from the lateral ground deformations. Current design codes significantly vary on how to combine inertia and kinematic demands. Recent research on soil-foundation-structure interaction suffers from lack of experiment-based data. There is a serious …


Distributionally Robust Optimization Utilizing Facility Location Problems, Elijah Kling Apr 2021

Distributionally Robust Optimization Utilizing Facility Location Problems, Elijah Kling

Civil and Environmental Engineering Undergraduate Honors Theses

Facility location problems are used in widespread application in transportation, freight, supply chain, and logistics problems. Models can be developed as deterministic, where all parameters are known, or robust, where a parameter has uncertainty. This thesis explores a new method for developing robust formulation and compares the implications of assuming values for this uncertain parameter. Two models are solved, and both are compared against their deterministic counterparts using numerical analysis. By manipulating the input parameters and considering real world implications of the solutions, either the robust or deterministic can show better performance.


Maximum Coverage Facility Location Drone Routing Problem With Multiple Trip Stops, Marie Roza Apr 2021

Maximum Coverage Facility Location Drone Routing Problem With Multiple Trip Stops, Marie Roza

Civil and Environmental Engineering Undergraduate Honors Theses

Integer linear optimization can be used to formulate routing problems as models to find optimal solutions given a set of inputs and constraints. In this research, Chauhan et al.'s publication, "Maximum coverage capacitated facility location problem with range constrained drones," is expanded upon by modeling a facility location problem with two-to-one drone deliveries. The model analyzes a set of potential facilities that are available to meet the demands of a set of demand points. The drone delivery routes are modeled with the assumption that each opened facility is assigned one drone that can fulfill up to two demand points’ demands …


Cei Hub Failure Following A Cascadia Earthquake Event: Preliminary Modeling Of A Liquid Fuel Spill In The Lower Willamette And Columbia Rivers, Mike Du Bose Apr 2021

Cei Hub Failure Following A Cascadia Earthquake Event: Preliminary Modeling Of A Liquid Fuel Spill In The Lower Willamette And Columbia Rivers, Mike Du Bose

Civil and Environmental Engineering Undergraduate Honors Theses

The Critical Energy Infrastructure (CEI) Hub in Northwest Portland, OR spans a six-mile stretch of the Lower Willamette River and stores 90% of Oregon’s liquid fuel supply and 100% of the jet fuel for PDX. The CEI Hub is also built entirely on liquefiable soils which are likely to fail during a Cascadia earthquake event. The purpose of this project was to model a liquid fuel spill in the Lower Willamette and Columbia Rivers using the CE-QUAL-W2 model. Several scenarios were developed to account for different environmental conditions, (e.g., high and low discharge years) and varying spill durations (e.g., rapid …


The Critical Energy Infrastructure (Cei) Hub: A Look Into The Seismic Fragility Of Oregon’S Fuel, Annecy Bal Apr 2021

The Critical Energy Infrastructure (Cei) Hub: A Look Into The Seismic Fragility Of Oregon’S Fuel, Annecy Bal

Civil and Environmental Engineering Undergraduate Honors Theses

This research evaluates the seismic vulnerability of the Critical Energy Infrastructure (CEI) Hub and the associated fuel repercussions for the expected 9.0 magnitude earthquake along the Cascadia Subduction Zone. The tanks in the CEI hub are analyzed based on size and content. The owners and secondary containment areas are discussed using the same parameters. Various analysis techniques are reviewed to determine the most appropriate seismic fragility estimate for the site. The seismic vulnerability is analyzed using fragility curves by Hazus, American Lifeline Alliance, and D'Amico. The fragility curves are applied to the CEI Hub to determine expected damage and the …


A Comparison Of Particulate Matter Deposition Onto Green Roof Species And White Roof In Portland, Oregon, Amelia Drake Apr 2021

A Comparison Of Particulate Matter Deposition Onto Green Roof Species And White Roof In Portland, Oregon, Amelia Drake

University Honors Theses

This study explores the following question: how do different green roof vegetation species contribute to particulate matter deposition relative to a white roof in Portland, Oregon? To answer this question, rinse water from two species of vegetation and rinse water from a white roof were filtered to measure the mass of particles found on these leaves. Leaf area was then determined in order to calculate the density of particles found on each surface. The resulting conclusions from this process clearly indicate that a larger density of particles collected on vegetative surfaces as opposed to the surface of the white roof. …


An Analysis Of Suspended Sediment Dynamics In A Partially Mixed Estuary, Riyadh Hamad Muttaleb Mar 2021

An Analysis Of Suspended Sediment Dynamics In A Partially Mixed Estuary, Riyadh Hamad Muttaleb

Dissertations and Theses

The purpose of this work is to investigate via data analysis and numerical modeling the SPM (suspended particulate matter) dynamics of a heavily contaminated partially urban estuary, the Lower Passaic River estuary (LPR), NJ. Accordingly, I investigate the quantity and mechanics of variation of fine and coarse SPM in the LPR via data analysis. Data analysis focuses on the parameters that affect SPM dynamics at six moored stations occupied during the Fall and Spring seasons, from near the estuary mouth to tidal freshwater. A 3D hydrodynamic model (Delft3D-FM) is used to analyze the effects of estuary topography on the dynamic …


Mit-S1 Constitutive Model Calibration For A Portland-Area Soil, Steven Ryan Young Jan 2021

Mit-S1 Constitutive Model Calibration For A Portland-Area Soil, Steven Ryan Young

Dissertations and Theses

Soils that are intermediate to sands and clays are a challenge for geotechnical engineers since most methods for interpreting soil properties or soil behaviors are based on sands or clays and do not address behaviors of intermediate soils. This is a particular challenge for engineers in the Portland-area where many of the major soil units are composed of intermediate soils. Analysis of intermediate soils is further challenged since many standard constitutive models are based on sandy or clay-like soils. However, the MIT-S1 constitutive model is capable of capturing intermediate soil behavior. A calibration of the MIT-S1 constitutive model for Portland-area …


Numerical Simulation Of Continuous Cone Penetration And Interpretation Of Cptu Dissipation Tests, Andrew Phillip Eugene Huffman Jan 2021

Numerical Simulation Of Continuous Cone Penetration And Interpretation Of Cptu Dissipation Tests, Andrew Phillip Eugene Huffman

Dissertations and Theses

The piezocone penetration test (CPTu) is a commonly used method of geotechnical site investigation. The CPTu is especially useful because it provides a nearly continuous data profile of in-situ soil behavior, which can be correlated to useful engineering parameters. However, limitations exist for interpretation of geotechnical properties from CPTu data and for numerical analysis of cone penetration problems. The research presented in this thesis examines interpretation of coefficient of consolidation from CPTu dissipation test data and implementation of an algorithm to advance numerical simulation of cone penetration problems. This thesis presents analysis of CPTu dissipation responses from field-measured and numerically …


Small Scale Plasma Gasification Of Municipal Solid Waste, Keith Male Jan 2021

Small Scale Plasma Gasification Of Municipal Solid Waste, Keith Male

Civil and Environmental Engineering Master's Project Reports

The goal of this project was to develop a prototype plasma gasification system to treat municipal solid waste (MSW) with minimal regulated emissions in a footprint small enough to be transported for a wide range of applicability. This project started with a review of current MSW treatment methods and of the emissions produced from thermal breakdown of MSW. A review of air quality regulations and emission control technologies was then used to select the emission control systems to be used for a small-scale plasma gasification system.

This plasma gasification system began with a plasma torch and cooling system being designed, …