Engineering Commons^™

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

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 …

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

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 …

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 …

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

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 …

A Comparison Of Bicyclists’ Performance Characteristics At Urban, Suburban, And Dedicated Path Intersections In Oregon, Kirk Paulsen, Christopher M. Monsere, Sam R. Thompson, Miguel A. Figliozzi

Civil and Environmental Engineering Faculty Publications and Presentations

This presentation provides an overview of the following research objectives

• To develop operational guidelines for timing and phasing of bicycle-specific traffic signals or modifications that can be made to existing signals to better accommodate bicycles.
• To develop engineering guidelines for the design of bicycle-specific traffic signals.

Evaluation Of The Performance Of The Sydney Coordinated Adaptive Traffic System (Scats) On Powell Boulevard In Portland, Or, Miguel A. Figliozzi, Christopher Monsere

Civil and Environmental Engineering Faculty Publications and Presentations

The Sydney Coordinated Adaptive Traffic System (SCATS) is used to mitigate traffic congestion along urban arterial corridors. Although there has been research on SCATS' performance, this report combines three different areas of research about SCATS that are not known to be represented in any research literature. These include: (a) the relationship between SCATS, traffic volumes, and Transit Signal Priority (TSP); (b) between TSP and traffic conditions; and (c) the correlation between signal timing and air quality; in particular, human exposure to the air pollutant PM2.5 at intersections. In addition, this research looked at the key factors affecting transit user exposure …

A Study Of Bicycle Signal Compliance Employing Video Footage, Sam R. Thompson, Kirk Paulsen, Christopher M. Monsere, Miguel A. Figliozzi

Civil and Environmental Engineering Faculty Publications and Presentations

An overview of bicycle signal compliance.

Definition And Properties Of Alternative Bus Service Reliability Measures At The Stop Level, Meead Saberi, Ali K. Zockaie, Wei Feng, Ahmed El-Geneidy

Civil and Environmental Engineering Faculty Publications and Presentations

The Transit Capacity and Quality of Service Manual (TCQSM) provides transit agencies with tools for measuring system performance at different levels of operation. Bus service reliability, one of the key performance measures, has become a major concern of both transit operators and users because it significantly affects user experience and service quality perceptions. The objective of this paper is to assess the existing reliability measures proposed by TCQSM and develop new ones at the bus stop level. The latter are not suggested as replacements for the existing measures; rather, they are complementary. Using empirical data from archived Bus Dispatch System …

Adaptation Of Classical Tidal Harmonic Analysis To Nonstationary Tides, With Application To River Tides, Pascal Matte, David A. Jay, Edward D. Zaron

Civil and Environmental Engineering Faculty Publications and Presentations

One of the most challenging areas in tidal analysis is the study of nonstationary signals with a tidal component, as they confront both current analysis methods and dynamical understanding. A new analysis tool has been developed, NS_TIDE, adapted to the study of nonstationary signals, in this case, river tides. It builds the nonstationary forcing directly into the tidal basis functions. It is implemented by modification of T_TIDE; however, certain concepts, particularly the meaning of a constituent and the Rayleigh criterion, are redefined to account for the smearing effects on the tidal spectral lines by nontidal energy. An error estimation procedure …

Driver Behavior In The Presence Of Pedestrians At Signalized Intersections Operating The Flashing Yellow Arrow, David Hurwitz, Christopher M. Monsere

Civil and Environmental Engineering Faculty Publications and Presentations

This presentation provides an overview of the research on driver behavior in response to the Flashing Yellow Arrow (FHA) in in the presence of pedestrians

Examining Consumer Behavior And Travel Choices, Kelly J. Clifton, Christopher Devlin Muhs, Sara Morrissey, Tomás Morrissey, Kristina Marie Currans, Chloe Ritter

Civil and Environmental Engineering Faculty Publications and Presentations

This study represents a first attempt to answer a few of the questions that have arisen concerning multimodal transportation investments and the impacts of mode shifts on the business community. This research aims to merge the long history of scholarly work that examines the impacts of the built environment on non-work travel with the relatively new interest in consumer spending by mode of travel. This empirical study of travel choices and consumer spending across 89 businesses in the Portland metropolitan area shows there are important differences between the amounts customers spend on average at various businesses by their mode of …

Model For Acid-Base Chemistry In Nanoparticle Growth (Mabnag), Taina Yli-Juuti, Kelley Barsanti, L. Hildebrandt Ruiz, Antti-Jussi Kieloaho, U. Makkonen, Tuukka Petäjä, Taina Ruuskanen, Markku Kulmala, Ilona Riipinen

Civil and Environmental Engineering Faculty Publications and Presentations

Climatic effects of newly-formed atmospheric secondary aerosol particles are to a large extent determined by their condensational growth rates. However, all the vapours condensing on atmospheric nanoparticles and growing them to climatically relevant sizes are not identified yet and the effects of particle phase processes on particle growth rates are poorly known. Besides sulfuric acid, organic compounds are known to contribute significantly to atmospheric nanoparticle growth. In this study a particle growth model MABNAG (Model for Acid-Base chemistry in NAnoparticle Growth) was developed to study the effect of salt formation on nanoparticle growth, which has been proposed as a potential …

Positive Matrix Factorization Of Pm2.5 - Eliminating The Effects Of Gas/Particle Partitioning Of Semivolatile Organic Compounds, Mingjie Xie, Kelley Barsanti, Michael P. Hannigan, Steven J. Dutton, Sverre Vedal

Civil and Environmental Engineering Faculty Publications and Presentations

Gas-phase concentrations of semi-volatile organic compounds (SVOCs) were calculated from gas/particle (G/P) partitioning theory using their measured particle-phase concentrations. The particle-phase data were obtained from an existing filter measurement campaign (27 January 2003-2 October 2005) as a part of the Denver Aerosol Sources and Health (DASH) study, including 970 observations of 71 SVOCs (Xie et al., 2013). In each compound class of SVOCs, the lighter species (e.g. docosane in n-alkanes, fluoranthene in PAHs) had higher total concentrations (gas + particle phase) and lower particle-phase fractions. The total SVOC concentrations were analyzed using positive matrix factorization (PMF). Then the results were …

Analyzing Experimental Data And Model Parameters: Implications For Predictions Of Soa Using Chemical Transport Models, Kelley Barsanti, Annmarie G. Carlton, Serena H. Chung

Civil and Environmental Engineering Faculty Publications and Presentations

Despite critical importance for air quality and climate predictions, accurate representation of secondary organic aerosol (SOA) formation remains elusive. An essential addition to the ongoing discussion of improving model predictions is an acknowledgement of the linkages between experimental conditions, parameter optimization and model output, as well as the linkage between empirically-derived partitioning parameters and the physicochemical properties of SOA they represent in models. In this work, a "best available" set of SOA modeling parameters is selected by comparing predicted SOA yields and mass concentrations with observed yields and mass concentrations from a comprehensive list of published smog chamber studies. Evaluated …