Charles E. Via Jr. Department of Civil and Environmental Engineering

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https://hdl.handle.net/10919/23747

The Charles E. Via, Jr. Department of Civil and Environmental Engineering, which is ranked in the top 10 accredited civil and environmental engineering departments by the US News and World Report survey, is one of the largest programs in the United States. The Department has 46 full-time faculty, 657 undergraduate, and 400 graduate students. Civil engineers are the principal designers, constructors, operators, and caretakers of many of the constructed facilities and systems that contribute to the high quality of life enjoyed in the United States. The Charles E. Via, Jr. Department of Civil and Environmental Engineering offers educational programs in all areas of civil engineering practice.

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2012 Via Report
(Virginia Tech, 2012)
This is the 2012 annual report for the Charles E. Via Jr. Department of Civil and Environmental Engineering.
2013 Via Report
(Virginia Tech, 2013)
This is the 2013 annual report for the Charles E. Via Jr. Department of Civil and Environmental Engineering.
2014 Via Report
(Virginia Tech, 2014)
This is the 2014 annual report for the Charles E. Via Jr. Department of Civil and Environmental Engineering.
2015 Via Report
(Virginia Tech, 2015)
Department head’s message: Greetings from Blacksburg! Once again it is our pleasure to present the annual edition of the Via Report. I hope you enjoy the excellent articles on several of the outstanding research efforts that are in progress within the department. The work highlighted in these articles supports students in the department and serves society in general, particularly in the Commonwealth, as many of the issues that our faculty are researching are highly important in Virginia. Rest assured that these are but a few of the many great things in progress!
2016 Via Report
(Virginia Tech, 2016)
Department head’s message: Greetings from Blacksburg! Once again it is our pleasure to present the annual edition of the Via Report. This year’s report is especially memorable because it is the 30th edition. We will have the opportunity to recognize the current Via scholars, and alumni of the program at our annual Via Banquet in December. I know that the Via family would be proud of the work these students are doing and their service to society in general. I hope you enjoy the excellent articles on several of the outstanding research efforts that are in progress within the department.
2017 Via Report
(Virginia Tech, 2017)
This is the 2017 annual report for the Charles E. Via Jr. Department of Civil and Environmental Engineering.
2018 Via Report
(Virginia Tech, 2018)
This is the 2018 annual report for the Charles E. Via Jr. Department of Civil and Environmental Engineering.
2019 Via Report
(Virginia Tech. Charles E. Via Jr. Department of Civil and Environmental Engineering, 2019)
This is the 2019 annual report for the Charles E. Via Jr. Department of Civil and Environmental Engineering.
3D + Time Reconstruction: Designing Optimal Camera Parameters
Helsel, Michelle; Salomon, Abraham Lama; Moen, Cristopher D. (2015-08-01)
Three dimensional plus time reconstructions are an emerging concept in the civil engineering industry. The application possibilities are continuing to develop, resulting in an expansive range of projects. Proper image based modeling should utilize different camera parameters depending on the individual application. Currently, research examining the optimal camera settings for 3D reconstruction quality is limited. Knowing the ideal camera parameters and how each parameter will affect the modeling utilized for image reconstruction settings will improve modeling quality of 3D reconstructions. This paper examines the effective methods for improving reconstruction features based on picture quality. Camera settings tested include depth of field, shutter speed, ISO light sensitivity, resolution, and the number of pictures taken to be utilized in the 3D reconstruction. The variables also incorporate changes in lighting types, as well as material surface reflections. Distinct trends can be identified within the data set with respect to the mentioned variables.
3D Hybrid of Layered MoS2/Nitrogen-Doped Graphene Nanosheet Aerogels: An Effective Catalyst for Hydrogen Evolution in Microbial Electrolysis Cells
Hou, Yang; Zhang, Bo; Wen, Zhenhai; Cui, Shumao; Guo, Xiaoru; He, Zhen; Chen, Junhong (The Royal Society of Chemistry, 2014-06-18)
Microbial fuel cells (MFCs) have been conceived and intensively studied as a promising technology to achieve sustainable wastewater treatment. However, doubts and debates arose in recent years regarding the technical and economic viability of this technology on a larger scale and in a real-world applications. Hence, it is time to think about and examine how to recalibrate this technology's role in a future paradigm of sustainable wastewater treatment. In the past years, many good ideas/approaches have been proposed and investigated for MFC application, but information is scattered. Various review papers were published on MFC configuration, substrates, electrode materials, separators and microbiology but there is lack of critical thinking and systematic analysis of MFC application niche in wastewater treatment. To systematically formulate a strategy of (potentially) practical MFC application and provide information to guide MFC development, this perspective has critically examined and discussed the problems and challenges for developing MFC technology, and identified a possible application niche whereby MFCs can be rationally incorporated into the treatment process. We propose integration of MFCs with other treatment technologies to form an MFC-centered treatment scheme based on thoroughly analyzing the challenges and opportunities, and discuss future efforts to be made for realizing sustainable wastewater treatment.
Accelerated Corrosion Testing of ASTM A1010 Stainless Steel
Hebdon, Matthew H.; Groshek, Isaac (American Institute of Steel Construction, 2018-04-11)
ASTM A1010 (recently adopted as ASTM A709 Gr50CR) is a material which has advantageous corrosion properties. It is a low-grade stainless steel which forms a protective patina and has been marketed as an alternative to other bridge steels and corrosion protection methods due to its corrosion resistance in highly corrosive environments. However, the material is currently available in plate form only, and several of the applications in the United States were required to use alternative materials when constructing and connecting secondary members to the A1010 plate girders. This paper addresses the corrosion behavior of A1010 in several different details relating to recent applications in the US. An accelerated corrosion study was performed which simulated a highly corrosive environment typical of the environment justifying the use of A1010. The research investigated the resulting galvanic corrosion and its effect on the corrosion rate of A1010 plates, several different common bridge steels, and typical fastener materials. In addition, common surface preparation methods were evaluated for their aesthetic effect during patina formation.
Acceptance Procedures for New and Quality Control Procedures for Existing Types of Corrosion-Resistant Reinforcing Steel
Stephen R. Sharp; Larry J. Lundy; Harikrishnan Nair; Moen, Cristopher D.; Josiah B. Johnson; Sarver, Brian E. (Virginia Center for Transportation Innovation and Research, 2011-06-01)
As the Virginia Department of Transportation (VDOT) continues to move forward with implementing the use of corrosion-resistant reinforcing (CRR) bars, it is important for VDOT to have a means of characterizing the candidate bars as well as ensuring that the quality of approved CRR bars is preserved. This is vital to ensure the bars respond physically in a manner that is consistent with VDOT's expectations. The purpose of this study was to provide VDOT's Materials Division with a method/specification for evaluating CRR bars. The study determined that visual assessment cannot be relied on to determine bar type. Further, steel fabricator markings cannot be relied on to identify the type of steel. However, when questions arise regarding the identification of bars, magnetic sorting provides a quick and easy method for differentiating between magnetic and nonmagnetic alloys. If more quantitative results are required, X-ray fluorescence provides a practical and much-needed method for positively identifying bars. Physically, the bars differ among producers. Relative rib area should be monitored as it also varies among producers. Further, alloying changes not only the corrosion resistance but also other important properties. The results of uniaxial tensile tests showed that the stress-strain behavior, elongation, and reduction in cross-section upon fracture could vary significantly for different CRR alloys. Therefore, mechanical testing, in addition to corrosion testing, of CRR is necessary to identify the most cost-effective bars with acceptable properties. Finally, the study determined that quality control measures need to be established to ensure VDOT receives the corrosion protection it needs. Further, care should be taken when relying upon international standards for acceptance criteria. The report recommends that VDOT's Materials Division implement the set of test methods provided in the appendices of this report as Virginia Test Methods for CRR acceptance criteria. To simplify the implementation of CRR in Virginia and elsewhere, VDOT's Materials Division should work with the American Association of State Highway and Transportation Officials to develop a single specification for the testing and acceptance of CRR. VDOT's Materials Division should also investigate retrofitting the uniaxial tensile test equipment with a non-contact extensometer to guarantee that stress vs. strain measurements of CRR can be made and ensure the yield strength is determined
Access Control Design on Highway Interchanges
Rakha, Hesham A.; Flintsch, Alejandra Medina; Arafeh, Mazen; Abdel-Salam, Abdel-Salam Gomaa; Dua, Dhruv; Abbas, Montasir M. (Virginia Center for Transportation Innovation and Research, 2008-01-01)
The adequate spacing and design of access to crossroads in the vicinity of freeway ramps are critical to the safety and traffic operations of both the freeway and the crossroad. The research presented in this report develops a methodology to evaluate the safety impact of different access road spacing standards. The results clearly demonstrate the shortcomings of the AASHTO standards and the benefits of enhancing them. The models developed as part of this research were used to compute the crash rate associated with alternative section spacing. The study demonstrates that the models satisfied the statistical requirements and provide reasonable crash estimates. The results demonstrate an eight-fold decrease in the crash rate when the access road spacing increases from 0 to 300 m. An increase in the minimum spacing from 90 m (300 ft) to 180 m (600 ft) results in a 50 percent reduction in the crash rate. The models were used to develop lookup tables that quantify the impact of access road spacing on the expected number of crashes per unit distance. The tables demonstrate a decrease in the crash rate as the access road spacing increases. An attempt was made to quantify the safety cost of alternative access road spacing using a weighted average crash cost. The weighted average crash cost was computed considering that 0.6, 34.8, and 64.6 percent of the crashes were fatal, injury, and property damage crashes, respectively. These proportions were generated from the field observed data. The cost of each of these crashes was provided by VDOT as $3,760,000, $48,200, and $6,500 for fatal, injury, and property damage crashes, respectively. This provided an average weighted crash cost of $43,533. This average cost was multiplied by the number of crashes per mile to compute the cost associated with different access spacing scenarios. These costs can assist policy makers in quantifying the trade-offs of different access management regulations.
Accumulation of di-2-ethylhexyl phthalate from polyvinyl chloride flooring into settled house dust and the effect on the bacterial community
Velazquez, Samantha; Bi, Chenyang; Kline, Jeff; Nunez, Susie; Corsi, Rich; Xu, Ying; Ishaq, Suzanne L. (2019-11-22)
Di-2-ethylhexyl phthalate (DEHP) is a plasticizer used in consumer products and building materials, including polyvinyl chloride flooring material. DEHP adsorbs from material and leaches into soil, water, or dust and presents an exposure risk to building occupants by inhalation, ingestion, or absorption. A number of bacterial isolates are demonstrated to degrade DEHP in culture, but bacteria may be susceptible to it as well, thus this study examined the relation of DEHP to bacterial communities in dust. Polyvinyl chloride flooring was seeded with homogenized house dust and incubated for up to 14 days, and bacterial communities in dust were identified at days 1, 7, and 14 using the V3-V4 regions of the bacterial 16S rRNA gene. DEHP concentration in dust increased over time, as expected, and bacterial richness and Shannon diversity were negatively correlated with DEHP concentration. Some sequence variants of Bacillus, Corynebacterium jeddahense, Streptococcus, and Peptoniphilus were relatively more abundant at low concentrations of DEHP, while some Sphingomonas, Chryseobacterium, and a member of the Enterobacteriaceae family were relatively more abundant at higher concentrations. The built environment is known to host lower microbial diversity and biomass than natural environments, and DEHP or other chemicals indoors may contribute to this paucity.
Adaptive Traffic Signal Control: Game-Theoretic Decentralized vs. Centralized Perimeter Control
Elouni, Maha; Abdelghaffar, Hossam M.; Rakha, Hesham A. (MDPI, 2021-01-03)
This paper compares the operation of a decentralized Nash bargaining traffic signal controller (DNB) to the operation of state-of-the-art adaptive and gating traffic signal control. Perimeter control (gating), based on the network fundamental diagram (NFD), was applied on the borders of a protected urban network (PN) to prevent and/or disperse traffic congestion. The operation of gating control and local adaptive controllers was compared to the operation of the developed DNB traffic signal controller. The controllers were implemented and their performance assessed on a grid network in the INTEGRATION microscopic simulation software. The results show that the DNB controller, although not designed to solve perimeter control problems, successfully prevents congestion from building inside the PN and improves the performance of the entire network. Specifically, the DNB controller outperforms both gating and non-gating controllers, with reductions in the average travel time ranging between 21% and 41%, total delay ranging between 40% and 55%, and emission levels/fuel consumption ranging between 12% and 20%. The results demonstrate statistically significant benefits of using the developed DNB controller over other state-of-the-art centralized and decentralized gating/adaptive traffic signal controllers.
Addressing the Contribution of Indirect Potable Reuse to Inland Freshwater Salinization
Bhide, Shantanu V.; Grant, Stanley B.; Parker, Emily A.; Rippy, Megan A.; Godrej, Adil N.; Kaushal, Sujay S.; Prelewicz, Gregory; Saji, Niffy; Curtis, Shannon; Vikesland, Peter J.; Maile-Moskowitz, Ayella; Edwards, Marc A.; Lopez, Kathryn; Birkland, Thomas A.; Schenk, Todd (2021-02-02)
Inland freshwater salinity is rising worldwide, a phenomenon called the freshwater salinization syndrome (FSS). We investigate a potential conflict between managing the FSS and indirect potable reuse, the practice of augmenting water supplies through the addition of reclaimed wastewater to surface waters and groundwaters. From time-series data collected over 25 years, we quantify the contributions of three salinity sources—a wastewater reclamation facility and two rapidly urbanizing watersheds—to the rising concentration of sodium (a major ion associated with the FSS) in a regionally important drinking water reservoir in the Mid-Atlantic United States. Sodium mass loading to the reservoir is primarily from watershed runoff during wet weather and reclaimed wastewater during dry weather. Across all timescales evaluated, sodium concentration in the reclaimed wastewater is higher than in outflow from the two watersheds. Sodium in reclaimed wastewater originates from chemicals added during wastewater treatment, industrial and commercial discharges, human excretion, and down-drain disposal of drinking water and sodium-rich household products. Thus, numerous opportunities exist to reduce the contribution of indirect potable reuse to sodium pollution at this site, and the FSS more generally. These efforts will require deliberative engagement with a diverse community of watershed stakeholders and careful consideration of the local political, social, and environmental context.
Aerosol microdroplets exhibit a stable pH gradient
Wei, Haoran; Vejerano, Eric P.; Leng, Weinan; Huang, Qishen; Willner, Marjorie R.; Marr, Linsey C.; Vikesland, Peter J. (2018-07-10)
Suspended aqueous aerosol droplets (< 50 mu m) are microreactors for many important atmospheric reactions. In droplets and other aquatic environments, pH is arguably the key parameter dictating chemical and biological processes. The nature of the droplet air/water interface has the potential to significantly alter droplet pH relative to bulk water. Historically, it has been challenging to measure the pH of individual droplets because of their inaccessibility to conventional pH probes. In this study, we scanned droplets containing 4-mercaptobenzoic acid-functionalized gold nanoparticle pH nanoprobes by 2D and 3D laser confocal Raman microscopy. Using surface-enhanced Raman scattering, we acquired the pH distribution inside approximately 20-mu m-diameter phosphate-buffered aerosol droplets and found that the pH in the core of a droplet is higher than that of bulk solution by up to 3.6 pH units. This finding suggests the accumulation of protons at the air/water interface and is consistent with recent thermodynamic model results. The existence of this pH shift was corroborated by the observation that a catalytic reaction that occurs only under basic conditions (i.e., dimerization of 4-aminothiophenol to produce dimercaptoazobenzene) occurs within the high pH core of a droplet, but not in bulk solution. Our nanoparticle probe enables pH quantification through the cross-section of an aerosol droplet, revealing a spatial gradient that has implications for acid-base-catalyzed atmospheric chemistry.
Aggregated responses of human mobility to severe winter storms: An empirical study
Wang, Yan; Wang, Qi; Taylor, John E. (PLOS, 2017-12-07)
Increasing frequency of extreme winter storms has resulted in costly damages and a disruptive impact on the northeastern United States. It is important to understand human mobility patterns during such storms for disaster preparation and relief operations. We investigated the effects of severe winter storms on human mobility during a 2015 blizzard using 2.69 million Twitter geolocations. We found that displacements of different trip distances and radii of gyration of individuals' mobility were perturbed significantly. We further explored the characteristics of perturbed mobility during the storm, and demonstrated that individuals' recurrent mobility does not have a higher degree of similarity with their perturbed mobility, when comparing with its similarity to non-perturbed mobility. These empirical findings on human mobility impacted by severe winter storms have potential long-term implications on emergency response planning and the development of strategies to improve resilience in severe winter storms.
Aggregation and sedimentation of magnetite nanoparticle clusters
Vikesland, Peter J.; Rebodos, R. L.; Bottero, J. Y.; Rose, J.; Masion, A. (Royal Society of Chemistry, 2016-03-24)
Magnetite nanoparticles are redox active constituents of subsurface and corrosive environments. In this study, we characterized the aggregation and sedimentation behavior of well characterized magnetite nanoparticle clusters using dynamic light scattering (DLS), UV-vis-NIR spectroscopy, and small angle X-ray scattering (SAXS). Both unfunctionalized (NaOH-magnetite) and tetramethylammonium hydroxide (TMAOH-magnetite) surface functionalized nanoparticle clusters were employed. TMAOH-magnetite has a slightly smaller primary nanoparticle radius as determined by TEM (4 ± 0.7 nm vs. 5 ± 0.8 for NaOH-magnetite) and a smaller initial DLS determined cluster radius (<30 nm vs. 100–200 nm for NaOH-magnetite). Interestingly, in spite of its smaller initial nanoparticle cluster size, TMAOH-magnetite undergoes sedimentation more rapidly than NaOH-magnetite. This behavior is consistent with the more rapid aggregation of the smaller TMAOH-magnetite clusters as well as their lower fractal dimension, as determined by SAXS. This study illustrates that both nanoparticle cluster size and fractal dimension should be carefully considered when considering the environmental transport and fate of highly aggregated nanoparticles.
AgroSeek: a system for computational analysis of environmental metagenomic data and associated metadata
Liang, Xiao; Akers, Kyle; Keenum, Ishi M.; Wind, Lauren L.; Gupta, Suraj; Chen, Chaoqi; Aldaihani, Reem; Pruden, Amy; Zhang, Liqing; Knowlton, Katharine F.; Xia, Kang; Heath, Lenwood S. (2021-03-10)
Background Metagenomics is gaining attention as a powerful tool for identifying how agricultural management practices influence human and animal health, especially in terms of potential to contribute to the spread of antibiotic resistance. However, the ability to compare the distribution and prevalence of antibiotic resistance genes (ARGs) across multiple studies and environments is currently impossible without a complete re-analysis of published datasets. This challenge must be addressed for metagenomics to realize its potential for helping guide effective policy and practice measures relevant to agricultural ecosystems, for example, identifying critical control points for mitigating the spread of antibiotic resistance. Results Here we introduce AgroSeek, a centralized web-based system that provides computational tools for analysis and comparison of metagenomic data sets tailored specifically to researchers and other users in the agricultural sector interested in tracking and mitigating the spread of ARGs. AgroSeek draws from rich, user-provided metagenomic data and metadata to facilitate analysis, comparison, and prediction in a user-friendly fashion. Further, AgroSeek draws from publicly-contributed data sets to provide a point of comparison and context for data analysis. To incorporate metadata into our analysis and comparison procedures, we provide flexible metadata templates, including user-customized metadata attributes to facilitate data sharing, while maintaining the metadata in a comparable fashion for the broader user community and to support large-scale comparative and predictive analysis. Conclusion AgroSeek provides an easy-to-use tool for environmental metagenomic analysis and comparison, based on both gene annotations and associated metadata, with this initial demonstration focusing on control of antibiotic resistance in agricultural ecosystems. Agroseek creates a space for metagenomic data sharing and collaboration to assist policy makers, stakeholders, and the public in decision-making. AgroSeek is publicly-available at https://agroseek.cs.vt.edu/ .

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