Undergraduate Research

Undergraduate Sustainable Transportation Research Awards 

2017 UVM NCST Undergraduate Research Assistants

Student: Austin Kopec
Adviser: Ting Tan, Assistant Professor, Civil and Environmental Engineering
Title: Measuring adhesion between aggregates and REOB-modified asphalt binders using particle probe scanning force microscopy.
Research Description: Particle probe scanning force microscopy have been created to measure adhesion between aggregate minerals and asphalt binders in our lab. By creating particle probes using mineral microspheres, adhesive forces between primary aggregate components, i.e., silica, calcium carbonate and alumina, and plain or modified binders have been successfully quantified at microscale. Based on these results, the adhesive performance of different binders can be accurately assessed, which provides an effective approach to the research and production of high-performance, ecofriendly asphalt materials for pavements.

 

Students: Kaitlyn Fuller & Bonnie McMorrow
Adviser:
 
Ehsan Ghazanfari, Assistant Professor, Civil and Environmental Engineering
Title: Application of intelligent compaction for extending the life of transportation infrastructure
Research Description: 
To ensure long lasting performance of pavement materials and avoid significant maintenance and rehabilitation costs, it is necessary to achieve high quality and uniformly compacted materials. The limitations of conventional compaction techniques and current density based acceptance practice in roadway construction has led to non-uniform and unsatisfactory compaction of the pavement materials, which in turn has resulted in premature failure and short life time performance of the pavement in many cases. Intelligent Compaction (IC) technology has the potential to significantly improve the consistency of compaction, extend the pavement life service, and reduce the maintenance costs. These benefits will collectively improve the sustainability of highways, a critical component of transportation infrastructure. This technology can be significantly enhanced by employing inexpensive sensors embedded in loose materials before being compacted. Passive wireless sensing system has the potential to detect moisture changes and stiffness of geomaterials, and therefore can play a significant role in complementing the existing IC technology. Signatures from these sensors would then be tracked to assess effectiveness and uniformity of compaction.
Paving the way to implement IC technology in New England projects and including inexpensive, passive wireless sensing technologies will significantly improve the durability of pavements in roadway/highways construction as it (i) provides a system wide stiffness-based inspection practice; (ii) allows for real-time monitoring, identification of weak areas, and making informed decision on proper course of action during compaction. In addition, IC implementation in New England leads to potential savings in maintenance costs and extended service life highway/roadway pavements. Before the IC technology complemented with passive wireless sensing can be implemented routinely in projects, there is a need to develop robust quality assurance/quality control (QA/QC) specifications in order to transition from density- to stiffness-based practice. This can be achieved by analyzing data from existing field tests to evaluate the correlations between IC measurement values (in terms of stiffness) with in place density/moduli using spot test measurements and develop robust QA/QC specifications. The PI has access to data from IC field tests in Vermont and will train/work with the undergraduate student to analyze the data and develop QA/QC specifications.

 

Student:  Dunia Karzai
Adviser:
 
Dr. Mandar M. Dewoolkar, P.E., Professor & Chair
Title: 
Understanding microscopic and macroscopic hydraulic behavior of pervious concrete
Research Description: 
A variety of pervious concrete mix designs for improving durability with respect to freeze-thaw and salt application have been created through research funded by the Vermont Agency of Transportation and the University of Vermont Transportation Research Center. Studied variations included addition of a small amount of sand; replacement of cement with fly ash, slag and slag with silica fume, saltguard treatment, extending curing time and so on. The process is laborious because each variation requires multiple specimens for statistical significance for assessing the strength, hydraulic conductivity and freeze-thaw durability of PCP. The freeze-thaw testing lasts for about 100 days. It is hypothesized that the freeze-thaw and salt resistance of pervious concrete is closely tied to the pore sizes, their distribution, and hydraulic conductivity of the mortar that coats the aggregates. The pore structure changes as the mix constituents and their proportions change. There are hardly any studies examining these pore structures at the microscopic scale. This project will employ X-ray tomography and surface permeability mapping techniques and macroscopic hydraulic conductivity testing to evaluate the pore structure and hydraulic characteristics of these mortar pastes and relate them to the durability of PCP. All three devices are available in my laboratory.

 

Student: Rebecca Shedd
Adviser:
Britt A. Holmén, Professor, Civil & Environmental Engineering, UVM
Title: 
Measurement of real-­world vehicle operation using personal vehicle data loggers in low-­density rural areas
Research Description: 
Today’s vehicle and computer technology enable second-­by-­ second measurement of vehicle operation at high spatial resolution. These measurement devices are installed in any post‐1996 passenger vehicle and record vehicle speed, engine speed, and a number of other parameters based on the vehicle’s ECU (make and model dependent). The UVM TRC owns 10 vehicle OBD data loggers equipped with GPS and WiFi (manufactured by HEMData). Distribution of these loggers to environmental engineering students and faculty took place in AY 16‐17, with hours of data collected for driving in northern Vermont and New York states, regions of relatively low vehicle density. The goal of this project is to organize, analyze and characterize this real­‐world driving data and compare it to standard regulatory EPA driving cycles. Further, the real-­world data will be used to estimate vehicle fuel consumption and tailpipe emissions using the U.S. EPA’s MOVES model. Differences between real­‐world and regulatory drive cycle emissions will inform the regulatory community about rural driving, the need for real‐world driving measurements in these regions and possibly identify locations of special roadway characteristics with high deviations from laboratory cycles, indicating bias.

 

Student: Markus Ingelsson
Adviser:
Britt A. Holmén, Professor, Civil & Environmental Engineering, UVM
Title: 
Relating oxidation stage of biodiesel fuel blends to tailpipe ultrafine particle emissions
Research Description: 
Little information exists on how the organic chemical composition of one “drop-­in” sustainable liquid transportation fuel, biodiesel, changes with oxidation of the fuel’s fatty acid methyl esters (FAMEs). Unlike petroleum diesel fuel, the FAMEs in biodiesel are susceptible to oxidation during fuel storage. Few prior studies have examined how these changes in fuel composition affect the tailpipe emissions associated with use of biodiesel in real-­world fuel blends. The objective of this research is to quantify the relationships between biodiesel fuel characteristics, specifically those resulting from different levels of fuel oxidation, and the resulting ultrafine particle number distributions in light-duty diesel engine exhaust. Given the energy life-­cycle benefits of using recycled waste vegetable oil (WVO) compared to virgin oil feedstocks for biodiesel, the study is conducted with commercially available WVO B100 biodiesel and a 20% blend of this WVO with petrodiesel.
In summer 2017, work in the UVM Transportation Air Quality Laboratory (TAQLab), led by graduate student Jack Reed, involved completing biodiese emissions tests using the UVM light-­duty diesel engine testbed. As part of this data collection effort, a scanning mobility particle sizer (SMPS) instrument collected real-­time data on highly resolved particle number distributions (PNDs) during steady-­state testing of nine operating modes. Analysis of this SMPS data, together with chemical characterization of each tested fuel sample will take place during AY17-­18 and the REU student will contribute significantly to these efforts.

 

Student: Christopher Diehl
Adviser:
Britt A. Holmén, Professor, Civil & Environmental Engineering, UVM
Title:
Modeling hybrid-­electric passenger car tailpipe emission “hot spots” as a function of transportation network characteristics
Research Description: 
Full hybrid-­electric vehicles (HEVs) have improved fuel economy compared to conventional vehicles (CVs) partly due to the fact that the internal combustion engine (ICE) is off during part of each HEV driving trip. This electric-­only operation contributes to intermittent periods of zero on-­road emissions as well as zero fuel consumption. However, HEVs have smaller ICEs that may be operating under higher engine load than CVs, under certain vehicle operations. High engine load operating points as well as “restarts” of the ICE are associated with transient high tailpipe emission events that are localized in spatial extent, creating pollutant “hot spots”. High load operation is anticipated under high positive road grade, high speed and aggressive acceleration driving, operating characteristics that may be tied to network characteristics such as proximity to intersections and speed limit.
The UVM Transportation Air Quality Laboratory (TAQLab) collected one of the first comprehensive real‐world emissions and performance data sets by driving comparable HEV and CV Toyota Camry vehicles over a specified 52 km driving route in all seasons in Vermont. The database from this prior field effort will be leveraged in this project to develop a model that identifies the key transportation network characteristics that are highly associated with elevated emissions of ultrafine particles from HEV compared to CV. Because of the unique characteristics of full HEV propulsion – where the internal combustion engine is restarted frequently during any given trip – we test the hypothesis that the spatial locations of HEV “hot spots” will be different from the spatial locations of CV “hot spots”. Further, we will develop quantitative metrics of disaggregating measures of HEV Vehicle Specific Power (VSP, a measure of total vehicle power requirement to move from point A to point B on the roadway) into electric versus ICE propulsion components. Given that only the ICE propulsion component of VSP has associated tailpipe emissions, the developed model will enable forecasting of hybrid-­electric vehicle emissions as a function road network variables such as road grade, speed limit and traffic control type.

 

Student: Maxfield Green 
Adviser: Lisa Aultman-­Hall, Professor, Civil & Environmental Engineering, UVM
Title:
Mobile Apps for Long Distance Travel Data Collection (Spring 2018)
Research Description: 
 Long-­distance travel is a neglected type of travel in the demand models that are used to understand access, mobility and environmental impacts.  This omission is due to lack of data and mobile apps show promise to fill this data gap. In this project, the student will analyze pilot app data in order to move towards algorithms that can automate long distance travel behavior data collection thus reducing the burden on study participants and improving the accuracy of databases over those reported by recall. This work will be incorporated into the future activities of our research group by informing the approach to future research data collection, as well as informing possible future methods of data collection for VTrans and the statewide model. If this task is successful, the student can move towards use of a larger dataset and preparation of a journal paper for TRB in Summer 2018.

 

Student: Madeline Suender  
Adviser: 
Lisa Aultman-­Hall, Professor, Civil & Environmental Engineering, UVM
Title: Long Distance Travel Decisions and Model Structures
Research Description:  
In the Spring of 2016, our team placed a series of questions on the annual Vermonter Poll. Participants were asked to think about their last out-­of-­town overnight trip for personal reasons (like to visit family/friends or take a vacation). We collected destination location and travel mode. We also collected information regarding the order of mode and destination choice in order to inform whether joint or distinct choice models are used for demand modeling. The student will first use the destination information to calculate distance to destinations from the participant’s home. The student will then generate distance by highway and cost by airplane to destinations.  The order of decision-making questions will be tabulated and compared as a function of sociodemographic data. This database and analysis will inform long distance mode choice models that will be developed collaboratively with Auburn University in Summer 2018. A journal paper will be developed.

 

Student: Maxfield Green  
Adviser: 
Lisa Aultman-­Hall, Professor, Civil & Environmental Engineering, UVM
Title: Understanding Bicycle Ridership (Fall 2017)
Research Description:  
In Summer 2017, work primarily with the California Household Travel Survey (CHTS) data, but also Atlanta MPO data, considered bicycle ridership and commuting by race. The research objective was to evaluate whether bicycle use differed by race after controlling for other sociodemographic factors. Such a finding would either support or not support the widespread hypothesis about culture as a factor in bicycle use. Many researchers have gathered circumstantial evidence of the importance of culture for bicycling suggesting that non-­Whites do not bicycle in as large a number.  But no other group has enjoyed a dataset as large as the CHTS to be able to test this hypothesis numerically. Our analysis showed that race was an independent factor for commuting by bicycle but not for overall riding. This new award would be used in Fall 2017 to add data from Philadelphia to finalize the analysis and write the journal paper. 

Comments are closed