Civil and Environmental Engineering Commons^™

Avoiding Bus Bunching: From Theory To Practice, Ricardo Giesen

PSU Transportation Seminars

The problem of bus bunching in a high frequency service has been largely studied in the literature.

This phenomenon is produced by three main factors

(i) the variability in travel time between stops; (ii) variations in passenger demand; and (iii) drivers’ heterogeneity.

In order to tackle this phenomenon a wide range of control strategies have been proposed, however, none of them had been successfully implemented on a large transit network with high frequency services.

In this talk, we present a control scheme based on a rolling horizon optimization problem that has been successfully implemented for real-time control of two high …

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 …

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 …

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 …

Improving Walkability Through Control Strategies At Signalized Intersections, Sirisha Murthy Kothuri, Andrew Kading, Edward J. Smaglik, Christopher Sobie

TREC Final Reports

As cities and communities nationwide seek to develop Complete Streets that foster livability and accommodate all modes, signal timing control strategies that include pedestrians in the operational decision process are gaining importance. This research tested several efficiency-focused pedestrian treatments – coordination, actuated-coordination, free operation, short cycle lengths – and safety-focused treatment including leading pedestrian intervals and Barnes Dance. Using a software-in-the-loop simulation, the operational impacts of these treatments on all users (vehicles, heavy vehicles, bicyclists and pedestrians) at an intersection were evaluated. Results showed that among the efficiency-based treatments, free operation was most beneficial for reducing minor-street pedestrian delays. Both …

Workshop Synthesis: Measuring Attitudes And Perceptions In Quantitative Surveys, Kelly Clifton, Juan Antonio Carrasco

Civil and Environmental Engineering Faculty Publications and Presentations

This workshop engaged participants in discussion about issues in incorporating qualitative information, namely attitudes, perceptions, and other psychological-social factors into transport research and analysis. There are many challenges to collecting this information from respondents. This synthesis summarizes the workshop presentations and discussion where participants identified the various types of information desired, reviewed the current challenges in conducting this type of data collection, made recommendations for practice, and outlined an agenda for future research.

Development Of Self-Sensing Carbon Nanotube-Based Composites For Civil Infrastructure Applications, Thomas Schumacher, Erik T. Thostenson

Civil and Environmental Engineering Faculty Publications and Presentations

Presented at the 5th International Symposium on Sensor Science (I3S 2017), Barcelona, Spain, 27–29 September 2017.

Worldwide, civil infrastructure systems are aging and deteriorating due to maintenance neglect, increasing traffic, and an environment that is becoming increasingly more severe. In particular, bridges play a critical role in the transportation network. With limited monies available for maintenance and repair, a need exists for effective yet inexpensive solutions to strengthen and monitor bridges. This presentation provides an overview of the development of carbon nanotube (CNT)-based composites, which offer a means to strengthen and monitor a deteriorated bridge member simultaneously. CNT sensors are …

Differences Of Cycling Experiences And Perceptions Between E-Bike And Bicycle Users In The United States, Ziwen Ling, Christopher R. Cherry, John Macarthur, Jonathan X. Weinert

Civil and Environmental Engineering Faculty Publications and Presentations

E-bikes are bicycles that provide pedal-assistance to aid people in cycling. Because of the potential of promoting sustainable transportation, more attention has been focused on the e-bike market. This paper investigates the differences of the cycling experience and perceptions between e-bike and conventional bicycle users, using samples drawn from independent bicycle dealer customers. A total of 806 respondents in the United States took the on-line survey, including 363 e-bike-owning respondents. The results show that e-bikes play a more important role in utilitarian travel, such as commuting and running errands, compared to a conventional bicycle. Conventional bicycle-owning respondents use their bicycles …

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 …

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.

Relative Sea-Level Trends In New York City During The Past 1500 Years, Andrew C. Kemp, Troy D. Hill, Christopher H. Vane, Niamh Cahill, Philip M. Orton, Stefan A. Talke, Andrew C. Parnell, Kelsey Sanborn, Ellen K. Hartig

Civil and Environmental Engineering Faculty Publications and Presentations

New York City (NYC) is threatened by 21st-century relative sea-level (RSL) rise because it will experience a trend that exceeds the global mean and has high concentrations of low-lying infrastructure and socioeconomic activity. To provide a long-term context for anticipated trends, we reconstructed RSL change during the past ~1500 years using a core of salt-marsh sediment from Pelham Bay in The Bronx. Foraminifera and bulk-sediment δ¹³C values were used as sea-level indicators. The history of sediment accumulation was established by radiocarbon dating and recognition of pollution and land-use trends of known age in down-core elemental, isotopic, and pollen …

Issues In Trip Generation Methods For Transportation Impact Estimation Of Land Use Development: A Review And Discussion Of The State-Of-The-Art Approaches, Kristina Marie Currans

Civil and Environmental Engineering Faculty Publications and Presentations

As agencies develop more robust planning objectives for creating sustainable and livable communities, the research community has continued developing supportive tools and methods to provide more accurate and robust means for estimating transportation impacts for site-level development review. This paper is a review of the state-of-the-art trip generation methods for land use transportation impact estimation. First, it provides an overview of the more recent available and peer-reviewed estimation methods. Second, the authors offer a discussion of the successes of state-of-the-art approaches using common themes of research to identify corresponding consistency with theories of travel behavior and urban economics. These themes …

Accessibility, Income, And Person Trip Generation: Multilevel Model Of Activity At Food Retail Establishments In Portland, Oregon, Kristina Marie Currans, Kelly Clifton

Civil and Environmental Engineering Faculty Publications and Presentations

In the past decade, the methods for estimating multimodal transportation impacts of urban land use development have improved substantially. One assumption commonly made in these new methods is that overall person-trip rates at similarly-sized establishments of the same land use do not vary across a region. This is an assumption of convenience to permit the adjustment of ITE Trip Generation vehicle trip rates for use in different urban environments. However, this assumption is inconsistent with theories of urban economics, which recognize that businesses pay a premium to locate in areas with high levels of accessibility to attract more customers. In …

Coupling Of Sea Level And Tidal Range Changes, With Implications For Future Water Levels, Adam T. Devlin, David A. Jay, Stefan Talke, Edward D. Zaron, Jiayi Pan, Hui Lin

Civil and Environmental Engineering Faculty Publications and Presentations

Are perturbations to ocean tides correlated with changing sea-level and climate, and how will this affect high water levels? Here, we survey 152 tide gauges in the Pacific Ocean and South China Sea and statistically evaluate how the sum of the four largest tidal constituents, a proxy for the highest astronomical tide (HAT), changes over seasonal and interannual time scales. We find that the variability in HAT is significantly correlated with sea-level variability; approximately 35% of stations exhibit a greater than ±50 mm tidal change per meter sea-level fluctuation. Focusing on a subset of three stations with long records, probability …

A Practitioner's Guide To Urban Trip Generation, Kristina Marie Currans

TREC Project Briefs

In 1976, the Institute of Transportation Engineers (ITE) compiled their first Handbook of guidelines for evaluating development-level transportation impacts. Decades later, these methods are still ubiquitously used across the US and Canada. Only recently, with the third edition of the ITE Trip Generation Handbook, have new data and approaches been adopted. In this study NITC researcher Kristina Currans takes aim at understanding issues inherent in the collection and application of ITE’s data and methods in various urban contexts. This technology transfer guide touches on the main findings from this work.

A Validated Tropical-Extratropical Flood Hazard Assessment For New York Harbor, Philip M. Orton, T. M. Hall, Stefan A. Talke, Alan F. Blumberg, Nickitas Georgas, S. Vinogradov

Civil and Environmental Engineering Faculty Publications and Presentations

Recent studies of flood risk at New York Harbor (NYH) have shown disparate results for the 100 year storm tide, providing an uncertain foundation for the flood mitigation response after Hurricane Sandy. Here we present a flood hazard assessment that improves confidence in our understanding of the region's present-day potential for flooding, by separately including the contribution of tropical cyclones (TCs) and extratropical cyclones (ETCs), and validating our modeling study at multiple stages against historical observations. The TC assessment is based on a climatology of 606 synthetic storms developed from a statistical-stochastic model of North Atlantic TCs. The ETC assessment …

Webinar: State-Wide Pedestrian And Bicycle Miles Traveled: Can We Estimate It?, Krista Nordback

TREC Webinar Series

Heard of Vehicle Miles Traveled (VMT)? Wouldn’t it be great to know the corresponding value for walking and cycling?

This webinar discusses options for estimating the miles people walk and bicycle on the state-wide level, by investigating the practical considerations of trying to compute these values for one study state.

What strategies can be used, and what data sources do these require?

How do these strategies compare?

How do PMT/BMT estimates vary based on data?

Find out what researchers found and what obstacles they encountered when they tried to estimate bicycle and pedestrian miles traveled in the State of Washington.

Pricing And Reliability Enhancements In The San Diego Activity-Based Travel Model, Joel Freedman

PSU Transportation Seminars

The estimation of demand for priced highway lanes is becoming increasingly important to agencies seeking to improve mobility and find alternative revenue sources for the provision of transportation infrastructure.

However, many modeling tools fall short of what is required for robust estimates of demand with respect to toll and managed lanes in two key areas:

• The value-of-time is often aggregate and not consistently defined throughout the model system, and
• The reliability of transport infrastructure is rarely taken into account.

This presentation describes an effort which implemented recommendations of the Strategic Highway Research Program C04 and L03\L04 tracks on pricing and …

Safety Effectiveness Of Pedestrian Crossing Enhancements, Christopher M. Monsere, Miguel Figliozzi, Sirisha Kothuri, Ali Razmpa, Daniel R. Hazel

Civil and Environmental Engineering Faculty Publications and Presentations

Over the last decade, the Oregon DOT and other agencies have systematically implemented many pedestrian crossing enhancements (PCEs) across the state. This study explored the safety performance of these enhanced crossing in Oregon. Detailed data were collected on 191 crossings. Supplemental data items included crossing location information, route characteristics, surrounding land use and crossing enhancement descriptions. Pedestrian volume at the crossing locations was a highly desirable but unavailable data element. To characterize pedestrian activity, a method was developed to estimate ranges for pedestrian crosswalk activity levels based on the land use classification at the census block level and the presence …

Evaluation Of A Supervisor Training Program For Odot’S Ecodrive Program, Donald M. Truxillo, John Macarthur, Leslie B. Hammer, Talya N. Bauer

TREC Final Reports

Eco-driving consists of using energy-efficient approaches to driving aimed at reducing fuel consumption and, ultimately, CO2 emissions. A previous study found that an EcoDrive informational campaign was effective at increasing the use of eco-driving behaviors, but only when employees perceived that their supervisor supported the program and when they were personally motivated to perform the eco-driving behaviors. In order to build upon the findings of our previous study, the present study focused on increasing the use of eco-driving behaviors through an informational eco-driving campaign combined with supervisor training to support the use of eco-driving practices.

In this study we collected …

Experimental Investigation Of Cfrp Wrapped Square Non-Ductile Reinforced Concrete Columns, Hayder Lateef Al-Khafaji

Dissertations and Theses

The use of fiber-reinforced polymers (FRP) for retrofitting or strengthening deficient concrete columns noticeably increased in the past few decades. Plenty of research has been conducted on the behavior of FRP-strengthened circular concrete columns, but far less research has dealt with non-circular columns. In the current study, the focus was to investigate the behavior of square columns with low to medium grade concrete and low steel reinforcement that were strengthened using carbon fiber reinforced polymer (CFRP) wrap. In the experimental portion of this investigation, twelve short square reinforced concrete columns (5" x 5" in cross section and 12" high) were …

An Assessment Of Post-Encroachment Times For Bicycle-Vehicle Interactions Observed In The Field, A Driving Simulator, And In Traffic Simulation Models, Ali Razmpa

Dissertations and Theses

Most safety analysis is conducted using crash data. Surrogate safety measures, such as various time-based measures of time-to-collision can be related to crash potential and used to gain insight into the frequency and severity of crashes at a specific location. One of the most common and acknowledged measures is post-encroachment time (PET) which defines the time between vehicles occupying a conflicting space. While commonly used in studies of motor vehicle interactions, studies of PET for bicycle-vehicle interactions are few. In this research, the PET of bicycle-vehicle interactions measured in the field, a driving simulator, and in a micro-simulation are compared. …

Webinar: Transit Signal Priority Evaluation And Performance Measures, Miguel Figliozzi

TREC Webinar Series

Transit signal priority (TSP) can reduce transit delay at signalized intersections by making phasing adjustments. TSP is a relatively inexpensive tool to provide faster and more reliable transit service. This webinar addresses TSP real-word performance measures as well as data integration and evaluation challenges. Results of the TSP evaluation in an arterial corridor in Portland, Oregon indicate that a timely and effective TSP system requires a high degree of sophistication, monitoring, and maintenance. TSP timing is crucial to reduce transit delay.

Key takeaways include: performance measures, methodology, analysis of early green and red extension pros and cons, novel real-world results.

Exploring Length-Based Vehicle Count Data, Byad Ahmed

Civil and Environmental Engineering Master's Project Reports

The development of Intelligent Transportation Systems (ITS) requires high-quality traffic information within most urban areas worldwide, and under growing pressure for improving traffic management, there has been an increasing urge to collecting and monitoring of traffic data. One of the most reliable and recommended technology for drive thru or traffic control is the loop vehicle detection system. On the Portland freeway system, new software has been installed that allows the reporting of vehicle length in bins. This research investigates the use of this data (length based) by exploring time series analyses of the vehicle counts as freight and non-freight movement.

Laser Doppler Velocimetry Using A Modified Computer Mouse, Edward D. Zaron

Civil and Environmental Engineering Faculty Publications and Presentations

A computer mouse has been modified for use as a low-cost laser Doppler interferometer and used to measure the two-component fluid velocity of a flowing soap film. The mouse sensor contains two vertical cavity surface emitting lasers, photodiodes, and signal processing hardware integrated into a single package, approximately 1 cm2 in size, and interfaces to a host computer via a standard USB port. Using the principle of self-mixing interferometry, whereby laser light re-enters the laser cavity after being scattered from a moving target, the Doppler shift and velocity of scatterers dispersed in the flow are measured. Observations of the boundary …

Tidal-Fluvial And Estuarine Processes In The Lower Columbia River: Ii. Water Level Models, Floodplain Wetland Inundation, And System Zones, David A. Jay, Amy B. Borde, Heida Diefenderfer

Civil and Environmental Engineering Faculty Publications and Presentations

Spatially varying water-level regimes are a factor controlling estuarine and tidal-fluvial wetland vegetation patterns. As described in Part I, water levels in the Lower Columbia River and estuary (LCRE) are influenced by tides, river flow, hydropower operations, and coastal processes. In Part II, regression models based on tidal theory are used to quantify the role of these processes in determining water levels in the mainstem river and floodplain wetlands, and to provide 21-year inundation hindcasts. Analyses are conducted at 19 LCRE mainstem channel stations and 23 tidally exposed floodplain wetland stations. Sum exceedance values (SEVs) are used to compare wetland …

Minimum Conditions For Visible Mold Growth, G. A. Tsongas, Frank Riordan

Mechanical and Materials Engineering Faculty Publications and Presentations

Considerable confusion and misunderstanding exists over the conditions required for visible mold growth at a surface in buildings. That is evident in papers and articles authored by engineers and other scientists, including various ASHRAE, ASTM and Canada Mortgage Housing Corporation publications. One of the major problems is that many HVAC engineers, building scientists, practitioners and others believe there exists a single critical value of the relative humidity (RH) of the indoor or ambient air well away from surfaces, below which mold will not grow on surfaces. However, that is not the case. The purpose of this article is to clarify …

Torsional Strengthening Of Reinforced Concrete Beams Using Cfrp Composites, Ranj Rafeeq

Dissertations and Theses

Few decades ago, there were no guidelines for torsion design of reinforced concrete (RC) beams. Hence, many existing beams in older buildings have a lack of adequate torsional strength since they were not properly designed for torsion. One way to regain/rehabilitate adequate torsional strength is through application of externally bonded carbon fiber reinforced polymers (CFRP). To date, American Concrete Institute (ACI) code, as well as other building codes, do not have recommendations or provisions for strengthening RC beams for torsion using fiber-reinforced polymer (FRP) composites due to the inexistence of conclusive experimental and analytical data. Of the very limited works …

Utilizing Egocentric Video And Sensors To Conduct Naturalistic Bicycling Studies, Feng Liu, Miguel A. Figliozzi

TREC Final Reports

Existing data collection methods are mostly designed for videos captured by stationary cameras and are not designed to follow cyclists along a route or to integrate other sensor data. The goals of this research are: a) to develop a platform to collect naturalistic video bicycling data, b) to develop a methodology to integrate video data with other sensors that measure cyclists’ position and comfort levels, and c) to apply the platform and data collection methodology to a real-world route. This research effort has successfully integrated video and sensor data to describe cyclists’ comfort levels along a route. It was found …

Multiple New-Particle Growth Pathways Observed At The Us Doe Southern Great Plains Field Site, Anna L. Hodshire, Michael J. Lawler, Jun Zhao, John Ortega, Coty Jen, Taina Yli-Juuti, Jared F. Brewer, Jack K. Kodros, Kelley C. Barsanti, Dave R. Hanson, Peter H. Mcmurry, James N. Smith, Jeffery R. Pierce

Civil and Environmental Engineering Faculty Publications and Presentations

New-particle formation (NPF) is a significant source of aerosol particles into the atmosphere. However, these particles are initially too small to have climatic importance and must grow, primarily through net uptake of low volatility species, from diameters ∼ 1 to 30–100 nm in order to potentially impact climate. There are currently uncertainties in the physical and chemical processes associated with the growth of these freshly formed particles that lead to uncertainties in aerosol-climate modeling. Four main pathways for new-particle growth have been identified: condensation of sulfuric-acid vapor (and associated bases when available), condensation of organic vapors, uptake of organic acids …