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Portland State University

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Full-Text Articles in Civil and Environmental Engineering

Benchtop Minimal-Intervention Anaerobic Digestion Of Vegetarian Food Waste For Ph And Methane Production: Conceivability And Control Study, Emily J. Heleva-Ponaski Apr 2014

Benchtop Minimal-Intervention Anaerobic Digestion Of Vegetarian Food Waste For Ph And Methane Production: Conceivability And Control Study, Emily J. Heleva-Ponaski

Civil and Environmental Engineering Undergraduate Honors Theses

Cities around the world transport large quantities of waste to landfills at a great expense to their residents, infrastructures, and environments. The objective of this study was to run an anaerobic food waste digester with minimal interference or maintenance. One specific goal of this research was to evaluate the relationship between anaerobic food waste and pH. Two benchop digesters were started with vegetarian food waste collected from the Portland State University campus. Measurements were collected over the course of the digestion process. Due to low pH and lack of biogas production, the digesters were buffered with sodium carbonate and seeded …


An Analysis Of Bicycle-Vehicle Interactions At Signalized Intersections With Bicycle Boxes, William Robert Farley Mar 2014

An Analysis Of Bicycle-Vehicle Interactions At Signalized Intersections With Bicycle Boxes, William Robert Farley

Dissertations and Theses

A before-and-after analysis was performed at eleven intersections where a bike box was installed in Portland, Oregon to explore the safety effects of the treatment. Video data were gathered prior to installation at 14 intersections where a bike box installation was planned by the Portland Bureau of Transportation. Cameras were set up to capture three full twenty-four hour days (72 hours) of data for each intersection from Tuesday through Thursday. Of the 14 original selected intersections, 11 intersections actually received the bike box treatment. Video data were again gathered for these intersections after the installation of the bike box for …


Bicycle Facilities And The Uptake Of Air Pollution By Active Travelers, Alexander Y. Bigazzi, Miguel A. Figliozzi, James F. Pankow, Wentai Luo, Lorne M. Isabelle Mar 2014

Bicycle Facilities And The Uptake Of Air Pollution By Active Travelers, Alexander Y. Bigazzi, Miguel A. Figliozzi, James F. Pankow, Wentai Luo, Lorne M. Isabelle

Civil and Environmental Engineering Faculty Publications and Presentations

Outlines the research of urban bicyclists' facilities and the uptake of air pollution by active travelers in urban Portland, OR. Outlines the research goals, beginning data collection methods, intake/uptake, modeling results, conclusions and the next steps for future work with the collected data set of direct uptake measurements.


More Urban Form, Fewer Auto Trips, Kelly J. Clifton Feb 2014

More Urban Form, Fewer Auto Trips, Kelly J. Clifton

TREC Project Briefs

Trip generation refers to the number of vehicle trips that are predicted to originate in a given zone. The Institute of Transportation Engineers (ITE) publishes standard trip generation rates for various land use types, but these rates are primarily measured in low-density suburban areas. There is national interest in building data that expands upon the existing ITE trip generation rates to include sites located in a multi-modal context.

In areas that have a more compact urban form, better access to transit and a greater mix of land uses, fewer vehicle trips may be generated there than ITE rates indicate. However, …


Time-Variable Refraction Of The Internal Tide At The Hawaiian Ridge, Edward D. Zaron, Gary D. Egbert Feb 2014

Time-Variable Refraction Of The Internal Tide At The Hawaiian Ridge, Edward D. Zaron, Gary D. Egbert

Civil and Environmental Engineering Faculty Publications and Presentations

The interaction of the dominant semidiurnal M2 internal tide with the large-scale subtidal flow is examined in an ocean model by propagating the tide through an ensemble of background fields in a domain centered on the Hawaiian Ridge. The background fields are taken from the Simple Ocean Data Assimilation (SODA) ocean analysis, at 2-month intervals from 1992 through 2001. Tides are computed with the Primitive Equation Z-coordinate Harmonic Analysis of Tides (PEZ-HAT) model by 14-day integrations using SODA initial conditions and M2 tidal forcing. Variability of the tide is found to occur primarily as the result of propagation through …


The Small Volume Autonomous Water Sampler (Svaws): An Innovative, Cost- Effective, Adaptable Protocol, Nicholas B. Fitzgerald Jan 2014

The Small Volume Autonomous Water Sampler (Svaws): An Innovative, Cost- Effective, Adaptable Protocol, Nicholas B. Fitzgerald

Dissertations and Theses

As of 2007, U.S. pesticide use stood at 1.1 billion pounds with 80% of all usage in agriculture. Such realities pose a potentially dangerous threat to our surface water bodies. This research provides a detailed analysis of the design, operation and field testing of a prototype water sampler, the Small Volume Autonomous Water Sampler (SVAWS). The research includes a discussion of the design and construction of the SVAWS. Seven USGS employees operated the SVAWS in a number of different states and conditions in order to collect samples for pesticide analysis. Field-testing outcomes of the SVAWS were measured through a Participant …


Occurrence Of Synthetic Amino-Polycarboxylate Chelating Compounds In Oregon Surface Waters, Nathan A. Hersey Jan 2014

Occurrence Of Synthetic Amino-Polycarboxylate Chelating Compounds In Oregon Surface Waters, Nathan A. Hersey

Civil and Environmental Engineering Master's Project Reports

Cation sequestering compounds are contained in many industrial, commercial and personal care products. The most widely used chelating agents, EDTA and DTPA, are commonly found in natural and industrial settings. When chelating compounds are present, the activity and transport of metal cations in the environment and the uptake of metals in natural systems can be affected. Surface water samples from across the United States were analyzed, as well as local collection and analysis of surface waters and wastewater treatment plant effluent from around Northwest Oregon. Results indicate presence of synthetic chelating compounds in areas with human activity, and absence in …


Seismic Retrofitting Of Existing Structures, Cetin Sahin Jan 2014

Seismic Retrofitting Of Existing Structures, Cetin Sahin

Civil and Environmental Engineering Master's Project Reports

This research project will give a brief presentation about earthquake resistant design and the methodology about seismic evaluation and rehabilitation of existing structures. It also provides certain aspects of computer software modeling against seismic loads and shows the necessity of seismic upgrading in a steel moment-frame building.

The seismic evaluation process consists of investigating if the structure meets the defined target structural performance levels. The main goal during earthquakes is to assure that building collapse doesn’t occur and the risk of death or injury to people is minimized and beyond that to satisfy post-earthquake performance level for defined range of …


Making Bridges Outlast Rising Waters, Daniel Cox Jan 2014

Making Bridges Outlast Rising Waters, Daniel Cox

TREC Project Briefs

During Hurricanes Ivan in 2004 and Katrina in 2005, at least 11 highway and railroad bridges along the U.S. Gulf Coast were damaged by wave forces. The spans of these bridges typically rested on bent column supports, and were attached to the supports by a variety of connection methods. Failure of these connections caused bridge spans to be washed away when the water rose high enough to lift them off. To build bridges that can withstand such forces, engineers must be able to estimate the effects the forces will have.

Investigator Daniel Cox of Oregon State University has conducted wave …


A Comparative Assessment Of Crowded Source Travel Time Estimates: A Case Study Of Bluetooth Vs Inrix On A Suburban Arterial, Fahad Fasha Alhajri Jan 2014

A Comparative Assessment Of Crowded Source Travel Time Estimates: A Case Study Of Bluetooth Vs Inrix On A Suburban Arterial, Fahad Fasha Alhajri

Civil and Environmental Engineering Master's Project Reports

Travel time is one of the most widely used measures of traffic performance monitoring for the transportation systems. It is a simple concept that refers to the time required to traverse between two points of interest. Travel time is communicated and used by a wide variety of audience such as commuters, media reporters, and transportation engineers and planners. Recent developments within the wireless communication area made it possible to collect travel time data at a relatively low cost. These emerging technologies include mobile phone based technologies, in-vehicle navigation technologies and automatic vehicle identification technologies. Although these technologies offer a great …


Evaluation Of Truck Signal Priority At N Columbia Blvd And Martin Luther King Jr. Blvd Intersection: Vissim Micro Simulation Analysis Of Truck Signal Priority, Maisha Mahmud Jan 2014

Evaluation Of Truck Signal Priority At N Columbia Blvd And Martin Luther King Jr. Blvd Intersection: Vissim Micro Simulation Analysis Of Truck Signal Priority, Maisha Mahmud

Civil and Environmental Engineering Master's Project Reports

Given the importance of over growing freight transportation system worldwide, engineers and planners are faced with the challenge of improving freight service in urban area using low cost measure. Truck Signal Priority is one of the strategy that can be used to improve operational efficiency with enhance safety benefits (red light running) of freight service, without major capital investment. In light to this interest this study focus on evaluating the impacts of freight signal priority on a high truck density intersection like N Columbia Blvd and NE Martin Luther King Jr. Blvd. Using a simulation tool, VISSIM, these impacts were …


Geospatial Analysis Of Rural Motor Vehicle Traffic Crashes In Oregon, Saad Nayef Almutairi Jan 2014

Geospatial Analysis Of Rural Motor Vehicle Traffic Crashes In Oregon, Saad Nayef Almutairi

Civil and Environmental Engineering Master's Project Reports

This research examines the spatial extent of crashes in and around city boundaries in the state of Oregon in the U.S.A. For this study, a summary of fatalities data for the year 2006 obtained from NHTSA's report (2009), crash data for the year 2012, and city boundaries were obtained from ODOT "Oregon Department of Transportation" FTP: www.odot.state.or.us. In order to differentiate between the urban and rural crashes, city boundaries were used to find the numbers of urban and rural crashes. Outside areas of this urban-rural boundary were divided into further boundaries of 2.5 miles. An intersection tool in ArcMap …


Application Of Ce-Qual-W2 On Tigris River In Iraq, Muhanned Al-Murib Jan 2014

Application Of Ce-Qual-W2 On Tigris River In Iraq, Muhanned Al-Murib

Civil and Environmental Engineering Master's Project Reports

The Tigris River is the eastern member of the two great rivers in Iraq. Two big rivers pass through Iraq, Mesopotamia. Tigris and Euphrates Rivers with their tributaries form a major river system in the Middle East. Four riparian countries, Turkey, Syria, Iran, and Iraq, share the Tigris River basin area and Iraq has the majority of this basin area. The total length of the Tigris is 1850 km from which 1418 km is within Iraq. A study area of 880 km from Mosul dam to Kut barrage is modeled using a water quality CE-QUAL-W2 model. CE-QUAL-W2 is a two-dimensional …


Wider Dissemination Of Household Travel Survey Data Using Geographical Perturbation Methods, Kelly J. Clifton, Steven R. Gehrke Jan 2014

Wider Dissemination Of Household Travel Survey Data Using Geographical Perturbation Methods, Kelly J. Clifton, Steven R. Gehrke

Civil and Environmental Engineering Faculty Publications and Presentations

Public agencies spend vast amounts of money collecting information about passenger travel in household travel surveys. These data are valuable for the rich and detailed information they provide, which contribute to regional and statewide travel demand models. These data have utility beyond travel demand modeling in their application to transportation policy and travel behavior research. As the demand on these data increase, so have the quantity of information collected. Detailed geospatial referencing of the home, work and other travel destinations are common practice and permit the integration with other spatially archived data sources, such as land use characteristics, transportation system …


Testing And Strengthening Bridge Connections, Christopher Higgins, Peter Dusicka, Michael Scott Jan 2014

Testing And Strengthening Bridge Connections, Christopher Higgins, Peter Dusicka, Michael Scott

TREC Project Briefs

Researchers evaluate and improve the strength of gusset plate connections, essential pieces in bridge design that can fail due to buckling.


Making Concrete From Recycled Materials, Jason Ideker Jan 2014

Making Concrete From Recycled Materials, Jason Ideker

TREC Project Briefs

Making concrete out of recycled concrete aggregate, or RCA, can be a sustainable and cost-saving alternative to other aggregates. However, the quality of concrete made with RCA is dependent on the quality of the recycled material used. OTREC researchers Jason Ideker of Oregon State University and Jennifer Tanner of the University of Wyoming, with graduate student researchers Matthew P. Adams and Angela Jones, sought to determine some of the primary concerns involved with the use of RCA and to arrive at methods of assessing its durability for use in new concrete.

Alkali-silica reaction occurs in concrete over time, causing it …


Turbulent Kinetic Energy And Coherent Structures In A Tidal River, Stefan A. Talke, Alexander R. Horner-Devine, C. Chris Chickadel, Andrew T. Jessup Dec 2013

Turbulent Kinetic Energy And Coherent Structures In A Tidal River, Stefan A. Talke, Alexander R. Horner-Devine, C. Chris Chickadel, Andrew T. Jessup

Civil and Environmental Engineering Faculty Publications and Presentations

We investigate the relationship between turbulence statistics and coherent structures (CS) in an unstratified reach of the Snohomish River estuary using in situ velocity measurements and surface infrared (IR) imaging. Sequential IR images are used to estimate surface flow characteristics via a particle-image-velocimetry (PIV) technique, and are conditionally sampled to delineate the surface statistics of bottom-generated CS, or boils. In the water column, we find that turbulent kinetic energy (TKE) production exceeds dissipation near the bed but is less than dissipation in the midwater column and that TKE flux divergence closes a significant portion of the measured imbalance. The surface …


Research Project Work Plan For Impact Of Cascadia Subduction Zone Earthquake On The Seismic Evaluation Criteria Of Bridges, Peter Dusicka Dec 2013

Research Project Work Plan For Impact Of Cascadia Subduction Zone Earthquake On The Seismic Evaluation Criteria Of Bridges, Peter Dusicka

Civil and Environmental Engineering Faculty Publications and Presentations

The goal of this project is to provide ODOT with the best rational estimate of ground acceleration values for designing new and retrofitting existing bridges. The objectives are to:

  • evaluate the hazard by contrasting the acceleration values from individual CSZ events to PSHA values
  • provide experimental evidence of damage difference under longer duration shaking expected from CSZ event


The Effect Of The Bicycle Detector Symbol And R10-22 Sign On Cyclist Queuing Position At Signalized Intersections, Stefan W. Bussey Oct 2013

The Effect Of The Bicycle Detector Symbol And R10-22 Sign On Cyclist Queuing Position At Signalized Intersections, Stefan W. Bussey

Civil and Environmental Engineering Undergraduate Honors Theses

The Manual of Traffic Control Devices (MUTCD) includes a roadway marking and accompanying explanatory sign which may be installed on public roads to help guide cyclists position themselves over detection at actuated traffic signals. While adopted into the MUTCD in 2003, little research is available on the effectiveness of the marking and sign. This study evaluates the influence that the roadway marking, roadway marking installed in conjunction with the explanatory sign, and an alternative detector marking comprised of the MUTCD marking installed over a one foot by two feet green rectangle, have on cyclist queuing position at actuated, signalized intersections. …


Evidence Supporting Treatment Practice Based Delineation Of Stormwater Runoff Zones, Jacob J. Gorski Oct 2013

Evidence Supporting Treatment Practice Based Delineation Of Stormwater Runoff Zones, Jacob J. Gorski

Dissertations and Theses

Particles mobilized by stormwater negatively affect receiving surface waters. Stormwater best management practices (BMPs) can reduce solids along with associated pollutants in runoff but engineers and environmental managers have been long vexed by the problem of choosing the optimal BMP for a given situation. A common BMP process for solids removal is sedimentation. This thesis addresses the question of whether the effectiveness (and thus choice) of a sedimentation device can be estimated (and thus optimized) from the particle size properties of runoff, which, in turn, could be associated with specific runoff zones or land uses. Presented here is a series …


Impacts Of Climate Change On The Seasonality Of Low Flows In 134 Catchments In The River Rhine Basin Using An Ensemble Of Bias-Corrected Regional Climate Simulations, Mehmet C. Demirel, Martijn Booij, Arjen Hoekstra Oct 2013

Impacts Of Climate Change On The Seasonality Of Low Flows In 134 Catchments In The River Rhine Basin Using An Ensemble Of Bias-Corrected Regional Climate Simulations, Mehmet C. Demirel, Martijn Booij, Arjen Hoekstra

Civil and Environmental Engineering Faculty Publications and Presentations

The impacts of climate change on the seasonality of low flows were analysed for 134 sub-catchments covering the River Rhine basin upstream of the Dutch-German border. Three seasonality indices for low flows were estimated, namely the seasonality ratio (SR), weighted mean occurrence day (WMOD) and weighted persistence (WP). These indices are related to the discharge regime, timing and variability in timing of low flow events respectively. The three indices were estimated from: (1) observed low flows; (2) simulated low flows by the semi-distributed HBV model using observed climate as input; (3) simulated low flows using simulated inputs from seven combinations …


2012 Portland Metropolitan Region Transportation System Performance Report, Robert L. Bertini, Dean George, Matthew Downey Oct 2013

2012 Portland Metropolitan Region Transportation System Performance Report, Robert L. Bertini, Dean George, Matthew Downey

Civil and Environmental Engineering Faculty Publications and Presentations

Our transportation system is a key ingredient in the economy, quality of life and urban fabric of the Portland metropolitan area. It has been stated in the past that it is not possible to manage our transportation system tomorrow unless we understand how it is performing today. In this spirit, Portland State University has been working with regional and statewide partners to develop new capabilities to measure, monitor and track the performance of the transportation system in real time and using archived data sources. We believe that it is possible to leverage these disparate data sources toward providing better transportation …


Characterization Of Secondary Organic Aerosol Precursors Using Two-Dimensional Gas Chromatography With Time Of Flight Mass Spectrometry (Gc×Gc/Tofms), Melissa Jordan Roskamp Sep 2013

Characterization Of Secondary Organic Aerosol Precursors Using Two-Dimensional Gas Chromatography With Time Of Flight Mass Spectrometry (Gc×Gc/Tofms), Melissa Jordan Roskamp

Dissertations and Theses

The oxidation of volatile organic compounds (VOCs) plays a role in both regional and global air quality through the formation of secondary organic aerosols (SOA). More than 1000TgC/yr of non-methane VOCs are emitted from biogenic sources (significantly greater than from anthropogenic sources). Despite this magnitude and potential importance for air quality, the body of knowledge around the identities, quantities and oxidation processes of these compounds is still incomplete (e.g., Goldstein & Galbally, 2007; Robinson et al., 2009). Two-dimensional gas chromatography paired with time-of-flight mass spectrometry (GC×GC/TOFMS) is a powerful analytical technique which is explored here for its role in better …


Transit Bus Fleet Age And Replacement Type Optimization, Miguel A. Figliozzi, Wei Feng, Jesse Boudart Sep 2013

Transit Bus Fleet Age And Replacement Type Optimization, Miguel A. Figliozzi, Wei Feng, Jesse Boudart

Civil and Environmental Engineering Faculty Publications and Presentations

Due to recent budget and fiscal constraints, it is ever more imperative for transit agencies to manage their fleets in an optimal way. Fleet data have consistently shown that bus operational and maintenance (O&M) per-mile costs increase as buses age. From a purely economic perspective, there is a cost tradeoff between the lower O&M costs of newer fleets and their higher initial capital costs. This tradeoff has a significant impact on the optimal timing of purchase and replacement decisions. Utilizing realistic cost data and an optimization modeling framework, we analyze (a) the impact of purchase timing decisions on fleet per-mile …


Rooftop Pv Impacts On Fossil Fuel Electricity Generation And Co2 Emissions In The Pacific Northwest, Daniel Albert Weiland Aug 2013

Rooftop Pv Impacts On Fossil Fuel Electricity Generation And Co2 Emissions In The Pacific Northwest, Daniel Albert Weiland

Dissertations and Theses

This thesis estimates the impacts of rooftop photovoltaic (PV) capacity on electricity generation and CO2 emissions in America's Pacific Northwest. The region's demand for electricity is increasing at the same time that it is attempting to reduce its greenhouse gas emissions. The electricity generated by rooftop PV capacity is expected to displace electricity from fossil fueled electricity generators and reduce CO2 emissions, but when and how much? And how can this region maximize and focus the impacts of additional rooftop PV capacity on CO2 emissions? To answer these questions, an hourly urban rooftop PV generation profile for 2009 was created …


Incorporating Chemical Activity And Relative Humidity Effects In Regional Air Quality Modeling Of Organic Aerosol Formation, Marguerite Colasurdo Marks Aug 2013

Incorporating Chemical Activity And Relative Humidity Effects In Regional Air Quality Modeling Of Organic Aerosol Formation, Marguerite Colasurdo Marks

Dissertations and Theses

Atmospheric particulate matter is known to have significant effects on human health, visibility, and global climate. The magnitudes of these effects, however, depend in complex ways on chemical composition, relative humidity, temperature, phase state, and other parameters. Current regional air quality models such as CMAQ (Community Multiscale Air Quality model) ignore many of these considerations, and consider that the formation of secondary organic aerosol (SOA) can be calculated by assuming thermodynamic ideality in the organic particulate matter (OPM) phase as well as negligible uptake of water into the OPM phase. Theoretical predictions and model simulations considering non-ideality and water uptake …


A Novel Approach To Flow Estimation In Tidal Rivers, Hamed Moftakhari Rostamkhani, David A. Jay, Stefan A. Talke, Tobias Kukulka, Peter D. Bromirski Aug 2013

A Novel Approach To Flow Estimation In Tidal Rivers, Hamed Moftakhari Rostamkhani, David A. Jay, Stefan A. Talke, Tobias Kukulka, Peter D. Bromirski

Civil and Environmental Engineering Faculty Publications and Presentations

Reliable estimation of river discharge to the ocean from large tidal rivers is vital for water resources management and climate analyses. Due to the difficulties inherent in measuring tidal-river discharge, flow records are often limited in length and/or quality and tidal records often predate discharge records. Tidal theory indicates that tides and river discharge interact through quadratic bed friction, which diminishes and distorts the tidal wave as discharge increases. We use this phenomenon to develop a method of estimating river discharge for time periods with tidal data but no flow record. Employing sequential 32 day harmonic analyses of tidal properties, …


The Application Of Smart Phone, Weight-Mile Truck Data To Support Freight-Modeling, Performance Measures And Planning, Katherine E. Bell, Miguel A. Figliozzi Aug 2013

The Application Of Smart Phone, Weight-Mile Truck Data To Support Freight-Modeling, Performance Measures And Planning, Katherine E. Bell, Miguel A. Figliozzi

Civil and Environmental Engineering Faculty Publications and Presentations

Oregon is one of the few states that currently charge a commercial truck weight-mile tax (WMT). The Oregon Department of Transportation (ODOT) has developed a data-collection system – Truck Road Use Electronics (TRUE) – to simplify WMT collection. The TRUE system includes a smart phone application that collects and records Global Positioning System (GPS) data. The TRUE data has enormous advantages over GPS data used in previous research due to its level of geographic detail and the potential to also integrate trip origin and destination, vehicle class, and commodity-type data. This research evaluates the accuracy of the TRUE data and …


Improving Vehicle Trip Generation Estimations For Urban Contexts: A Method Using Household Travel Surveys To Adjust Ite Trip Generation Rates, Kristina Marie Currans Jul 2013

Improving Vehicle Trip Generation Estimations For Urban Contexts: A Method Using Household Travel Surveys To Adjust Ite Trip Generation Rates, Kristina Marie Currans

Dissertations and Theses

The purpose of this research is to develop and test a widely available, ready-to-use method for adjusting the Institute of Transportation Engineers (ITE) Trip Generation Handbook vehicle trip generation estimates for urban context using regional household travel survey data. The ITE Handbook has become the predominant method for estimating vehicle trips generated by different land uses or establishment, providing a method for data collection and vehicle trip estimation based on the size of the development (e.g. gross square footage, number of employees, number of dwelling units). These estimates are used in traffic impact analysis to assess the amount of impact …


Exploring Data Quality Of Weigh-In-Motion Systems, Chengxin Dai Jul 2013

Exploring Data Quality Of Weigh-In-Motion Systems, Chengxin Dai

Dissertations and Theses

This research focuses on the data quality control methods for evaluating the performance of Weigh-In-Motion (WIM) systems on Oregon highways. This research identifies and develops a new methodology and algorithm to explore the accuracy of each station's weight and spacing data at a corridor level, and further implements the Statistical Process Control (SPC) method, finite mixture model, axle spacing error rating method, and data flag method in published research to examine the soundness of WIM systems. This research employs the historical WIM data to analyze sensor health and compares the evaluation results of the methods. The results suggest the new …