Engineering Commons^™

Structural Behavior Of Lap Shear Connections With Thermally Insulating Filler Plates, Salih Qasim Mahmood

Dissertations and Theses

This research consists of experimental load tests and numerical simulations of structural steel connections with various filler materials to study the effect of non-steel fillers on the connection strength. Non-steel fillers are used in the steel connections to provide thermal insulation by reducing thermal bridging. Eight specimens having steel and polypropylene filler plates of various thicknesses were tested in the laboratory. The collected data were compared to a Finite Element Analysis (FEA) using ABAQUS to validate the numerical results. After validation, three parametric studies were conducted using ABAQUS to provide insight into general behavior of connections with a variety of …

Utilizing High-Resolution Archived Transit Data To Study Before-And-After Travel-Speed And Travel-Time Conditions, Travis Bradley Glick

Dissertations and Theses

Travel times, operating speeds, and service reliability influence costs and service attractiveness. This paper outlines an approach to quantify how these metrics change after a modification of roadway design or transit routes using archived transit data. The Tri-County Metropolitan Transportation District of Oregon (TriMet), Portland's public transportation provider, archives automatic vehicle location (AVL) data for all buses as part of their bus dispatch system (BDS). This research combines three types of AVL data (stop event, stop disturbance, and high-resolution) to create a detailed account of transit behavior; this probe data gives insights into the behavior of transit as well as …

Multi-Dimensional Drought Risk Assessment Based On Socio-Economic Vulnerabilities And Hydro-Climatological Factors, Ali Ahmadalipour

Dissertations and Theses

Drought is among the costliest natural hazards developing slowly and affecting large areas, which imposes severe consequences on society and economy. Anthropogenic climate change is expected to exacerbate drought in various regions of the globe, making its associated socioeconomic impacts more severe. Such impacts are of higher concern in Africa, which is mainly characterized by arid climate and lacking infrastructure as well as social development. Furthermore, the continent is expected to experience vast population growth, which will make it more vulnerable to the adverse effects of drought. This study provides the first comprehensive multi-dimensional assessment of drought risk across the …

Analysis Of The Acid-Base Balance Of Mainstream Tobacco Smoke And Its Effect On The Gas/Particle Partitioning Of Nicotine, Amy Kathleen Devita-Mcbride

Dissertations and Theses

Tobacco smoke particulate matter (PM) is a complex mixture of condensed organic compounds, with about 5 to 10% water. Its general properties are similar in some respects to that of atmospheric organic aerosol PM and thus provides a useful surrogate when studying atmospheric PM. Due to its ability to undergo acid-base chemistry, nicotine is of particular interest in the tobacco smoke system. The gas/particle partitioning of nicotine depends on the protonation state of nicotine in the particles, so the distribution of nicotine between these phases provides a means of understanding the acid-base balance in the tobacco smoke system. The goal …

Elution Tailing Of Nonaqueous Phase Liquids In Porous Media, Louisa Orr

Civil and Environmental Engineering Undergraduate Honors Theses

A variety of porous media were studied to characterize contaminant dispersion over time. This work looked at a compilation of previously published studies to investigate the dependence of long term elution tailing trends on particular soil characteristics. Recession curve analysis was conducted on existing dispersed contaminant literature, to yield the low-concentration recession constant (K). The R² values correlating the soil properties to contaminant concentration ranged from 0.12494 to 0.95429. The low-concentration recession constant (K) values ranged from 0.9745407 0.9999988. The relationship between K and the soil properties porosity, organic carbon, and fines fraction is increasing. Bulk density and the …

Evaluating The Performance Of Contech's Stormfilter With Zpg Media Under The City Of Portland's 2016 Stormwater Management Manual Requirements For Manufactured Stormwater Treatment Technologies, Mawj T.H. Khammas

Civil and Environmental Engineering Master's Project Reports

Stormwater runoff is the water generated from excess rainfall or snowmelt that flows over impervious surfaces such as paved roads, parking lots, and on roofs, it often carries a variety of pollutants that adversely affect water quality in that region. Portland is a well-developed city; the majority of the streets are paved and impervious and will consequently generate a tremendous amount of stormwater this creates the necessity for management to help preserve and mimic natural hydrologic cycle through improving water quality. The StormFilter® with ZPG media, manufactured by CONTECH, is a manufactured stormwater treatment technology(MSTT) in which zeolite, perlite, and …

Issues In Urban Trip Generation, Kristina Marie Currans

Dissertations and Theses

In the 1976, the Institute of Transportation Engineers (ITE) compiled their first Handbook of guidelines and methods for evaluating development-level transportation impacts, specifically vehicular impacts (Institute of Transportation Engineers 1976). Decades later, these methods--essentially the same as when they were originally conceived--are used ubiquitously across the US and Canada. Only recently, with the guidelines in its third edition of the ITE's Trip Generation Handbook (Institute of Transportation Engineers 2014) new data and approaches have been adopted--despite substantial evidence that questions the accuracy of older data, automobile bias, and lack of sensitivity to urban contexts.

This dissertation contributes to this literature …

Design And Experimental Investigation Of 500kv Current Transformer Seismic Retrofit Utilizing Structure Rocking And Supplemental Damping With Self-Centering, Ilya S. Palnikov

Dissertations and Theses

Electrical substations perform a key role in electrical transmission and distribution; the ability for a substation to remain functional during and after a seismic event contributes significantly to the resilience of the clients supplied. Many legacy components currently installed in the main grid substations were designed with minimal consideration of lateral loads and are not qualified per IEEE693. One of the more critical high-voltage substation components that are vulnerable to earthquake damage is the 500kV freestanding current transformer (CT). The CT is particularly vulnerable due to the slenderness and mass distribution of the component. Current transformers are typically constructed from …

A Statistical Investigation Of Lower Columbia River Water Temperature, 1915-2003, Corina Christina Mae Overman

Civil and Environmental Engineering Undergraduate Honors Theses

The Columbia River is home to anadromous salmon populations that migrate upriver every year to spawn. These fish require cool water temperatures (T_w) to survive. In recent years, high summer T_w in the Columbia River has caused increased mortality of salmon. Different possible explanations for increased T_w include climate change, deforestation, and decreased summertime streamflow (Q) due to dams. In this study, robust linear regression models of T_w based on air temperature (T_a) and Q were developed to examine the change in T_w over time. The data was …

Utilization Of Remote Sensing In Drought Monitoring Over Iraq, Yousif Almamalachy

Dissertations and Theses

Agricultural drought is a creeping disaster that overshadows the vegetative cover in general and cropland specifically in Iraq, a country that was well known for its agricultural production and fertile soil. In the recent years, the arable lands in Iraq experienced increasing land degradation that led to desertification, economic losses, food insecurity, and deteriorating environment. Remote sensing is employed in this study and four different indices are utilized, each of which is derived from MODIS satellite mission products. Agricultural drought maps are produced from 2003 to 2015 after masking the vegetation cover. Year 2008 was found the most severe drought …

Rate-Limited Mass Transfer Of Trichloroethene, Deza R. Irving

Civil and Environmental Engineering Undergraduate Honors Theses

Trichloroethene (TCE) is a volatile and toxic contaminant commonly found in the subsurface. To help reduce the effects of this contaminant, it is important to understand the transport and fate behavior of TCE through the subsurface. As groundwater fills the void spaces of a porous media contaminated with pure-phase TCE, the TCE will dissolve into the water, contaminating the groundwater. It was expected that this dissolution would follow a first-order mass transfer process, suggesting that the rate of dissolution of TCE is dependent on the mass of TCE present in solution. The purpose of this study was to characterize the …

Emerging Pollutants In The Columbia River: A Simple Assessment Of Nonpoint Source Zones, Chulgi Kim

Civil and Environmental Engineering Undergraduate Honors Theses

Water quality modeling in the Columbia River Basin was conducted at the confluence of the Willamette and Columbia Rivers, river mile 101. The study area for this research consists of Sauvie Island, OR, and the surrounding areas of Vancouver, WA. Analysis of the region’s watershed and simple hydrologic calculations allowed for estimates of potential sources contributing to PBDEs in the Columbia River along river mile 101. This research included assessment of rainfall patterns and peak discharge rates in the areas along the rivers. A simple model of overland flow for the watershed was applied to estimate the area’s contribution to …

An Analytical System For Determining Disciplinary Vocabulary For Data-Driven Learning: An Example From Civil Engineering, Philippa Jean Otto

Dissertations and Theses

Data-driven learning (DDL), an inductive teaching approach in which students learn through corpus interaction, has gained recent traction as way to teach specialized vocabulary in English for Specific Purposes (ESP) classes. There is little research, however, that addresses how to choose specialized vocabulary for teaching with DDL.

This study addressed this gap in research by exploring the potential of a three-part analytical, corpus-based system for determining vocabulary to teach with DDL for a specific context of language use. This system included (1) identifying words that were significantly more frequent in a specialized expert corpus than in a corpus of general …

Land Use Mix And Pedestrian Travel Behavior: Advancements In Conceptualization And Measurement, Steven Robert Gehrke

Dissertations and Theses

Smart growth policies have often emphasized the importance of land use mix as an intervention beholding of lasting urban planning and public health benefits. Past transportation-land use research has identified potential efficiency gains achieved by mixed-use neighborhoods and the subsequent shortening of trip lengths; whereas, public health research has accredited increased land use mixing as an effective policy for facilitating greater physical activity. However, despite the celebrated transportation, land use, and health benefits of improved land use mixing and the extent of topical attention, no consensus has been reached regarding the conceptualization and measurement of this key smart growth principle …

Application Of Numerical Modeling To Study River Dynamics: Hydro-Geomorphological Evolution Due To Extreme Events In The Sandy River, Oregon, Sarkawt Hamarahim Muhammad

Dissertations and Theses

The Sandy River (OR) is a coastal tributary of the Columbia River and has a steep hydroshed 1316 square kilometers which is located on the western side of Mount Hood (elevation range 3 m to 1800 m). The system exhibits highly variable flow: Its average discharge is ~40 m³/s, and the highest recorded discharge was 1739 m³/s in 1964. In this study I model the geomorphic sensitivity of an 1800m reach located the downstream of the former Marmot Dam, which was removed in 2007. The hydro-geomorphic response to major flood has implications for system management and …

Hydrodynamic And Water Quality Modeling Of The Chehalis River Using Ce-Qual-W2, Sarah Van Glubt

Dissertations and Theses

The Chehalis River Basin is located in the southwest region of Washington State, originating in the Olympic Mountains and flowing to Grays Harbor and the Pacific Ocean. The Chehalis River is over 125 miles, exists within five counties, and flows through agricultural, residential, industrial, and forest land areas. Four major rivers discharge to the Chehalis River, as well as many smaller creeks, five wastewater treatment plants, and groundwater flows.

Flooding is a major problem in the relatively flat areas surrounding the cities of Chehalis and Centralia, with severe consequences for property, safety and transportation. As a result, construction of a …

Achieving Operational Seismic Performance Of Rc Bridge Bents Retrofitted With Buckling-Restrained Braces, Ramiro Andrés Gabriel Bazáez Gallardo

Dissertations and Theses

Typical reinforced concrete (RC) bridges built prior to 1970 were designed with minimum seismic consideration, leaving numerous bridges highly susceptible to damage following an earthquake. In order to improve the seismic behavior of substandard RC bridges, this study presents the seismic performance of reinforced concrete bridge bents retrofitted and repaired using Buckling-Restrained Braces (BRBs) while considering subduction zone earthquake demands. In order to reflect displacement demands from subduction ground motions, research studies were conducted to develop quasi-static loading protocols and then investigate their effect on structural bridge damage. Results suggested that subduction loading protocols may reduce the displacement ductility capacity …

Seismic Retrofit Case Study Of Reinforced Concrete Bridges With Buckling Restrained Braces, Michael K. Miotke

Civil and Environmental Engineering Master's Project Reports

Many highway bridges in Oregon have been designed with minimal considerations for seismic hazard and are in need of retrofit. Although buckling restrained braces (BRBs) are not necessarily a new concept, using them to seismically retrofit bridges is. This case study investigates the BRB retrofit concept as compared to traditional retrofit measures for a sample of typical vulnerable bridges in Oregon. The objectives of evaluating these cases were to determine the feasibility of the concept both in terms of performance as well as construction costs. This study builds on the ongoing research at Portland State University into the development of …

Seismic Evaluation Of 196kv Transformer Bushings, Joanne R. Shields

Civil and Environmental Engineering Master's Project Reports

Transformer bushings have shown to have an unsatisfactory performance during earthquakes and have therefore been chosen for further testing. How the bushings fail, and how this failure can be prevented has been analyzed. Two used 196 kV bushings made by General Electric were chosen for seismic testing at the iSTAR laboratory located at Portland State University in Portland, OR. The multiple objectives that brought about these tests were: to determine how the bushings failed due to gasket extrusion at the porcelain-flange connection and to verify that the failure was due to pure tipping and not sliding, to determine the damping …

City Of Gresham Stormwater Retrofit Master Plan, Teresa F. Huntsinger

Civil and Environmental Engineering Master's Project Reports

The Stormwater Retrofit Master Plan identifies more than 50 stormwater retrofit project opportunities across three watersheds in the City of Gresham. The retrofit projects are prioritized in a scoring system to evaluate the costs and benefits of diverse project sizes and types. Project types range from bioswales and planters in city parking lots and along arterial roads, to regional end-of-pipe facilities and retrofits of existing detention ponds. Top projects will move forward for further assessment, design and construction, helping the city achieve its water quality improvement goals. The scoring system may be used to evaluate additional projects in the future.

Impact Of Speed On Vehicle Safety On Urban Arterial Roadways, Andrew C. Vosper

Civil and Environmental Engineering Master's Project Reports

Vehicle speed has long been one, if not the primary contributing factor to crashes, influencing both the probability and severity. Within the Portland metro area arterials have the highest serious crash rate per road mile and vehicle miles travelled. (Metro, 2012) The purpose of this research is to compile vehicle speeds along select arterial roadways within the Portland metro area and comparing it to applicable crash data. The roadway segment of SE Foster Road between SE 52^nd avenues and SE 82^nd avenues was selected, due to the simplicity of the physical as-built roadway properties along with available Bluetooth …

Feasibility Determination Guide For The Road Diet Plus: A Five/Four-Lane To Two-Lane Road Diet, Michael Williams

Civil and Environmental Engineering Master's Project Reports

Road diets are a popular tool for corridor improvement. Road diets are normally defined as the conversion of a four-lane undivided road to a three-lane undivided road made up of two through lanes separated by a center two-way-left-turn-lane (known as a TWLTL). This new configuration has similar vehicular capacity, greater safety and frees up right-of-way for other uses.

This work examines the possibility of going one step, or one lane, further. What is the possibility of reducing five- or four-lane roads to two-lanes? If this is possible, what are the corridor characteristics within which this process would be feasible?

The …