Civil and Environmental Engineering Commons^™

Celebrating 20 Years Of The Exceed Teaching Workshop, Allen C. Estes, Stephen J. Ressler P.E., Camilla M. Saviz P.E., Brock E. Barry, Carol L. Considine, Dion Coward, Norman D. Dennis Jr., P.E., Scott R. Hamilton P.E., David S. Hurwitz, Tanya Kunberger P.E., Thomas A. Lenox, Tonya Lynn Nilsson, Leslie Nolen Cae, James J. O'Brien Jr., Robert James O'Neill, David A. Saftner, Kelly Salyards P.E., Ronald W. Welch P. E.

Engineering Technology Faculty Publications

In response to the clear need for faculty training, the American Society of Civil Engineers (ASCE) developed and funded Project ExCEEd (Excellence in Civil Engineering Education) which is celebrating its twentieth year of existence. For the past two decades, 38 ExCEEd Teaching Workshops (ETW) have been held at six different universities. The program has 910 graduates from over 267 different U.S. and international colleges and universities. The ExCEEd effort has transformed from one that relied on the grass roots support of its participants to one that is supported and embraced by department heads and deans. This paper summarizes the history …

Collaborative Strategies For Sea Level Rise Adaptation In Hampton Roads, Virginia, Carol Considine, Emily Steinhilber

Engineering Technology Faculty Publications

[Introduction] The Hampton Roads region is located in southeastern Virginia where the Chesapeake Bay meets the Atlantic Ocean. The region includes seventeen municipal governments and has a large federal government presence with 26 federal agencies represented (See Figure 1). The region has a population that exceeds 1.7 million and is home to the deepest water harbor on the U.S. East Coast. Hampton Roads' economy is dependent on the local waterways and houses the world's largest naval facility, the sixth largest containerized cargo complex and supports a thriving shipbuilding and repair industry as well as a tourism industry. However, the region's …

Modeling The Impacts Of Sea Level Rise On Storm Surge Inundation In Flood-Prone Urban Areas Of Hampton Roads, Virginia, Luca Castrucci, Navid Tahvildari

Civil & Environmental Engineering Faculty Publications

Hampton Roads is a populated area in the United States Mid-Atlantic region that is highly affected by sea level rise (SLR). The transportation infrastructure in the region is increasingly disrupted by storm surge and even minor flooding events. The purpose of this study is to improve our understanding of SLR impacts on storm surge flooding in the region. We develop a hydrodynamic model to study the vulnerability of several critical flood-prone neighborhoods to storm surge flooding under several SLR projections. The hydrodynamic model is validated for tide prediction, and its performance in storm surge simulation is validated with the water …

Manufacturing Applications Of The One-Dimensional Cutting Stock Problem As A Team Project, Hüseyin Sarper, Nebojsa I. Jaksic

Electrical & Computer Engineering Faculty Publications

This paper explains the beneficial and practical impact of operations research in two real manufacturing settings. Two manufacturing examples used in student projects were (1) cutting rails (80‘ or 40‘) to manufacture railroad frogs of many sizes and (2) cutting round metal rolls (12‘ to 20‘) to meet customer demands for various lengths of cuts. Student teams in Engineering of Manufacturing Processes and Operations Research courses wrote computer programs. The program first identified all possible patterns that can be cut out of a given stock length. Next, the program created a mathematical model (a text file) as an output. This …

Driving Factors On Runoff Change In The North Semiarid Rapidly Urbanization Watershed, Yong Bai, Rui-Zhong Gao, Xi-Xi Wang, Wei-Na Wang

Civil & Environmental Engineering Faculty Publications

The hydrological process of a watershed influences a lot on the local socioeconomic development. The analysis of runoff change caused by the rapid urbanization on the watershed is of important significance in the management and protection of the local water resource. In this study, based on the land use information from remotely sensed images, the hydrometeorological observation data and the social economy data from 1997 to 2015, the relationship between the influencing factors and the runoff trend in Wulanmulun River watershed was analyzed at different time scale using the improved Mann-Kendall Test and PCA (principal component analysis) method. The results …

Optimizing Nature-Based Features For Wave Dissipation And Land-Water Connectivity, Maura Boswell, Navid Tahvildari

Civil & Environmental Engineering Faculty Publications

Living shorelines integrate structural and natural features to stabilize the shoreline, through reduction of erosion from the wave climate, while keeping the connectivity between land and aquatic ecosystems. This study includes field study for two different types of living shoreline systems to quantify and compare their wave dissipation services and provide physics-based guidance for the design of living shoreline systems that are efficient in wave dissipation yet maximize land-water connectivity.

Combined Effect Of Storm Surge And Overland Flow On Flooding In A Coastal Urban Area, Navid Tahvildari, Akash Sahu, Yawen Shen, Mohamed Morsy, Jonathan Goodall

Civil & Environmental Engineering Faculty Publications

The coastal regions in the U.S. East Coast and the Gulf of Mexico are under the risk of storm surge and precipitation-driven flooding. The adverse impacts of climate change including sea level rise (SLR), potential increase in intensity and frequency of extreme storms, and increase in precipitation intensity increases the vulnerability of coastal communities to flooding. The common practice for flood hazard assessment in urban coastal areas can result in some errors as the effect of storm surge and overland flow are not considered simultaneously. In this study, we combine the results of two hydrodynamic models, one for overland flow …

A Picture Is Worth A Thousand Roads, Keith Pierce

News Items

No abstract provided.

Effects Of Vacuuming Pervious Concrete On Infiltration Rate, Demetrios E. Maurakis, Eugene G. Maurakis

Virginia Journal of Science

The objectives of this research were twofold: test the infiltration rate of pervious concrete before and after vacuum cleaning and assess infiltration variability over time. Infiltration tests were performed on a 558.2 m2 area of pervious concrete, divided into sixteen 0.35 m2 test areas in a parking area at the Science Museum of Virginia in Richmond, Virginia on five dates from November 4-December 30, 2013. Average infiltration rates (avg.= 22.8 and 36.3 L/m²/min) immediately after vacuuming were lower than those (avg.=30.7 and 41.3 L/m²/min) before vacuuming. We hypothesize that the vacuuming lifted materials towards the surface …

Quantifying Pollutant Removal Rates Of Bioretention Basins As A Stormwater Best Management Practice, Evan Nathanial Waagen

Civil & Environmental Engineering Theses & Dissertations

Water pollution is an ongoing problem that can be attributed to human activities. As world population increases and countries become more developed, this problem intensifies. Fortunately, the causes and solutions of water pollution are documented and have been implemented with various levels of success. These solutions, or Best Management Practices (BMPs), vary in type and function and remove pollutants from runoff prior to it reaching rivers, lakes, and other bodies of water. This study investigates bioretention basins, a specific group of BMPs, and presents analysis and prediction of their performance, of which our knowledge is incomplete in the existing literature. …

Holistic Approach In Microalgae Conversion To Bioproducts And Biofuels Through Flash Hydrolysis, Ali Teymouri

Civil & Environmental Engineering Theses & Dissertations

In recent years, the demand for renewable energy, mainly biomass has increased. The U.S. Energy Information Administration reported that more than 13.3% of the total energy production in the first seven months of 2017 was produced from a biomass source. Among all biomass resources, microalgae has brought a lot of attention due to their numerous advantages such as higher growth rate and productivity compared with the conventional energy crops, higher energy conversion efficiency by photosynthesis, and less water requirement than terrestrial crops. However, its development is far behind industrial production. Several research efforts across the globe have been concerned with …

Efficient Algorithms For Solving Size-Shape-Topology Truss Optimization And Shortest Path Problems, Gelareh B. Sanjabi

Civil & Environmental Engineering Theses & Dissertations

Efficient numerical algorithms for solving structural and Shortest Path (SP) problems are proposed and explained in this study. A variant of the Differential Evolution (DE) algorithm for optimal (minimum) design of 2-D and 3-D truss structures is proposed. This proposed DE algorithm can handle size-shape-topology structural optimization. The design variables can be mixed continuous, integer/or discrete values. Constraints are nodal displacement, element stresses and buckling limitations.

For dynamic (time dependent) networks, two additional algorithms are also proposed in this study. A heuristic algorithm to find the departure time (at a specified source node) for a given (or specified) arrival time …

Simulated Dynamics Of Soil Water And Pore Vapor In A Semi-Arid Sandy Ecosystem, Shohreh Pedram

Civil & Environmental Engineering Theses & Dissertations

Understanding dynamics of soil water content (SWC) and pore air relative humidity (RHpa), as influenced by wetting-drying cycles, is crucial for sustaining fragile ecosystems of desert lands across the world and needed for improving the prediction accuracy of global climate change. However, to date, such an understanding is still incomplete. The objective of this dissertation was to examine such dynamics at a typical desert site within the Horqin Sandy Land, located in Mongolian Plateau of north China. The examination was done by using a HYDRUS-1D computer simulation model and the continuous sensor-based soil water data for two calendar years. HYDRUS-1D …

Investigating Physical Processes Associated With Chesapeake Bay And Changjiang Estuary, Arash Niroomandi

Civil & Environmental Engineering Theses & Dissertations

Coastal and estuaries are landforms that not only have great impacts on large marine ecosystem, but also play a significant role in moderating or aggravating natural hazards and erosion risks that are expected to increase with climate change. This dissertation explores some of the concerns associated with coasts and coastal systems. In the second chapter, a thirty seven year wave hindcast (1979-2015) in Chesapeake Bay using NCEP's Climate Forecast System Reanalysis (CFSR) wind is presented. The long-term significant wave heights are generated by the third-generation nearshore wave model SWAN, which is validated using the wave height measurements at buoy stations …

Itsblue: A Distributed Bluetooth-Based Framework For Intelligent Transportation Systems, Ahmed Awad Alghamdi

Computer Science Theses & Dissertations

Inefficiency in transportation networks is having an expanding impact, at a variety of levels. Transportation authorities expect increases in delay hours and in fuel consumption and, consequently, the total cost of congestion. Nowadays, Intelligent Transportation Systems (ITS) have become a necessity in order to alleviate the expensive consequences of the rapid demand on transportation networks. Since the middle of last century, ITS have played a significant role in road safety and comfort enhancements. However, the majority of state of the art ITS are suffering from several drawbacks, among them high deployment costs and complexity of maintenance.

Over the last decade, …

Investigation And Analysis Of The Fluctuating Brominated To Total Trihalomethane Ratio In The Virginia Beach Distribution System, Christopher Steven Mihalkovic

Civil & Environmental Engineering Theses & Dissertations

An increasing trend in the brominated-trihalomethane to total-trihalomethane concentration ratio from 2001 to 2016 in the Virginia Beach water distribution system was established and investigated. This study aimed at identifying factors contributing to fluctuations in trihalomethane speciation in finished water. Reservoir management practices, treatment processes, and source water conditions were examined to quantitatively and qualitatively discern the impact of their variations on finished water THM speciation. Data on water quality constituents and parameters from the Moore’s Bridges Treatment Facility and within the Virginia Beach distribution system were examined to interpret spatial and temporal relationships with trihalomethane concentrations using established research …

A Comparative Study Of The Effects Of External Selection On Settleability And Formation Of Aerobic Granular Sludge, Tyler A. Brickles

Civil & Environmental Engineering Theses & Dissertations

Aerobic granular sludge (AGS) has shown much promise in the advancement of the wastewater treatment industry. AGS has been studied intensely since the early 1990’s due to highly desirable characteristics of nutrient removal efficiency, low footprint, and abnormally faster settling rates than conventional activated sludge. With the exception of a few on-going research projects, all AGS systems have been studied and implemented through the use of sequencing batch reactors (SBR). Recently, a novel approach to developing AGS and improving settling characteristics of activated sludge within conventional activated sludge (CAS) processes has being attempted through the use of external selection.

Activated …

Inertization, Utilization, And Safe Disposal Of Incineration Residues, Anil Mehrotra

Civil & Environmental Engineering Projects for D. Eng. Degree

Combustion of coal or Municipal Solid Waste (MSW) caused air pollution and produces solid residues which contain high levels of toxic elements. The toxic characteristics of residues generated from combustion of MSW in waste-to-energy plants are strictly controlled by Federal and State Waste Management Regulations. According to Resource Conservation and Recovery Act (RCRA), residue generated from combustion of MSW is considered hazardous and must be tested according to EPA Toxic Characteristics Leaching Procedure (TCLP) Method 1311 and suitably treated for its safe disposal to landfills. Experiments with various treatment chemicals as primary independent variable had earlier been conducted by several …

Algorithms For Constructing Vehicle Trajectories In Urban Networks Using Inertial Sensors Data From Mobile Devices, Umana Ahmed

Computational Modeling & Simulation Engineering Theses & Dissertations

Vehicle trajectories are an important source of information for estimating traffic flow characteristics. Lately, several studies have focused on identifying a vehicle’s trajectory in traffic network using data from mobile devices. However, these studies predominantly employed GPS coordinate information for tracking a vehicle’s speed and position in the transportation network. Considering the known limitations of GPS, such as, connectivity issues at urban canyons and underpasses, low precision of localization, high power consumption of device while GPS is in use, this research focuses on developing alternate methods for identifying a vehicle’s trajectory at an intersection and at a urban grid network …

Hydrologic Response Caused By Wetland Expansion At Huntley Meadows Park In Hybla Valley, Virginia, Stephen Fraser Stone

OES Theses and Dissertations

The goal of this study was to understand the effects of wetland expansion across a watershed. The 2013 restoration and expansion of the wetlands at Huntley Meadows Park (Fairfax County, VA) performed by Wetland Studies and Solutions, Inc. provided the opportunity to study this process. The 630 ha park contains more than 364 ha of freshwater emergent and freshwater forested wetlands. The restoration and expansion project used a subsurface vinyl-piling dam that impedes groundwater flow leaving the wetland, thus expanding the existing pond and the surrounding wetland.

This study used a network of more than twenty monitoring instruments making observations …

Behavior And Strength Of Rc Spandrel Members Under Unsymmetrical Bending And Torsion Including Cfrp Retrofitting, Muhammad Fahim

Civil & Environmental Engineering Theses & Dissertations

This dissertation presents the outcome of an experimental and theoretical investigation of the behavior and strength of reinforced concrete spandrel members both with and without carbon fiber reinforced polymer (CFRP) retrofitting. Both isolated spandrel members with L-shaped cross section as well as those integrated with reinforced concrete slabs are studied. A series of isolated spandrel members were tested under separate and combined actions of unsymmetrical bending and torsion. Six of these specimens were retrofitted externally with high-strength CFRP strips. Materially nonlinear analysis procedures are also formulated and programmed for the spandrel members with and without CFRP retrofitting. Furthermore, ultimate bending-torsion …

A Household Daily Non-Mandatory Activity Participation And Duration Modeling Accounting For Person Level Budget Constraints, Ivana Vukovic

Civil & Environmental Engineering Theses & Dissertations

A key methodological and behavioral innovative component in recent Activity-Based Models (ABMs) used for transportation planning is the household-level non-mandatory activity participation component. While traditional ABMs use a series of simple models to predict non-mandatory activity participation decisions in a sequential manner (which is often not correct), the Multiple Discrete Continuous Extreme Value (MDCEV) model can model both individual and joint non-mandatory activity participation and time allocation decisions in different out-of-home activities of all household members simultaneously. A key advantage of the MDCEV framework is that it accounts for complex intra-household interactions among different household members by allocating the total …

Behavior And Strength Of Non-Prestressed And Prestressed Hillman Composite Beam Including Cfrp Retrofitting, Wajid Khan

Civil & Environmental Engineering Theses & Dissertations

The Hillman Composite Beam (HCB) is a recent innovation used for the first time in 2008 for a bridge construction in USA. It essentially consists of an FRP outer shell, concrete arch inside the shell and steel strands used to tie the two ends of the arch. Being new in the field, the behavior of HCB has not been thoroughly studied. This dissertation presents a study of the flexural behavior and strength of HCB up to the collapse as well as explores the influence of using carbon reinforced polymer (CFRP) retrofitting and prestressed steel for a further increase in HCB …

Quantifying Cyanide Inhibition Of Nitrification And Developing Cost-Effective Treatment Processes, Germano M. Salazar-Benites

Civil & Environmental Engineering Theses & Dissertations

All wastewater treatment plants that operate multiple hearth furnaces (MHF) and are required to nitrify must manage the inhibitory effects of free cyanide (HCN, CN-) in the scrubber return flows due to inhibitory impacts on nitrifying bacteria.

HRSD Boat Harbor Treatment Plant (BHTP) a 25 MGD facility consisting of primary and secondary treatment, employs an anoxic selector process for nitrification and partial denitrification and operates a MHF. There is a desire to improve TN removal performance at BHTP due to an annual mass-based bubble permit limit on a combined discharge from seven HRSD plants, and there are no discharge limitations …

6 Field-Observed Cracking Of Paired Lightweight And Normalweight Concrete Bridge Decks, Tara L. Cavalline, Jeremy T. Calamusa, Amy M. Kitts, Brett Q. Tempest

Engineering Technology Faculty Publications

Research has suggested that conventional lightweight concrete can offer durability advantages due to reduced cracking tendency. Although a number of publications exist providing the results of laboratory-based studies on the durability performance of lightweight concrete (with lightweight coarse aggregate) and internally cured concrete (using prewetted lightweight fine aggregate), far fewer field studies of durability performance of conventional lightweight concrete bridge decks in service have been performed. This study was commissioned to provide insight to a highway agency on whether enhanced durability performance, and therefore reduced maintenance and longer lifecycles, could be anticipated from existing lightweight concrete bridge decks that were …

Data-Driven Spatial Modeling For Quantifying Networkwide Resilience In The Aftermath Of Hurricanes Irene And Sandy, Yuan Zhu, Kun Xie, Kaan Ozbay, Fan Zuo, Hong Yang

Computational Modeling & Simulation Engineering Faculty Publications

In recent years, the New York City metropolitan area was hit by two major hurricanes, Irene and Sandy. These extreme weather events disrupted and devastated the transportation infrastructure, including road and subway networks. As an extension of the authors' recent research on this topic, this study explored the spatial patterns of infrastructure resilience in New York City with the use of taxi and subway ridership data. Neighborhood tabulation areas were used as the units of analysis. The recovery curve of each neighborhood tabulation area was modeled with the logistic function to quantify the resilience of road and subway systems. Moran's …

Impact Of Connected Vehicles On Mitigating Secondary Crash Risk, Hong Yang, Zhenyu Wang, Kun Xie

Computational Modeling & Simulation Engineering Faculty Publications

Reducing the risk of secondary crashes is a key goal for effective traffic incident management. However, only few countermeasures have been established in practices to achieve the goal. This is mainly due to the stochastic nature of both primary and secondary crashes. Given the emerging connected vehicle (CV) technologies, it is highly likely that CVs will soon be able to communicate with each other through the ad-hoc wireless vehicular network. Information sharing among vehicles is deemed to change traffic operations and allow motorists for more proactive actions. Motorists who receive safety messages can be motivated to approach queues and incident …

Cfrp Retrofitting Schemes For Prestressed Concrete Box Beams For Highway Bridges, Hussein A. Herish, Zia Razzaq

Civil & Environmental Engineering Faculty Publications

This paper investigates various retrofitting schemes for a prestressed concrete box beam using carbon fiber reinforced polymer (CFRP) sheets with the goal of increasing flexural strength. A simply-supported box beam is studied with a constant uniformly distributed load and three gradually increasing concentrated loads proportional to HS20 truck loading of the Association of State Highway and Transportation Officials (AASHTO). Various retrofitting schemes are considered each with single, double, and triple CFRP sheets, respectively, installed in high compression and tension regions. Cross-sectional nonlinear moment-curvature relations are developed and coupled with a finite-difference solution algorithm to predict load-deflection relations for both retrofitted …

Water–Soil–Vegetation Dynamic Interactions In Changing Climate, Xixi Wang, Xuefeng Chu, Tingxi Liu, Xiangju Cheng, Rich Whittecar

Civil & Environmental Engineering Faculty Publications

Previous studies of land degradation, topsoil erosion, and hydrologic alteration typically focus on these subjects individually, missing important interrelationships among these important aspects of the Earth's system. However, an understanding of water–soil–vegetation dynamic interactions is needed to develop practical and effective solutions to sustain the globe's eco-environment and grassland agriculture, which depends on grasses, legumes, and other fodder or soil-building crops. This special issue is intended to be a platform for a discussion of the relevant scientific findings based on experimental and/or modeling studies. Its 12 peer-reviewed articles present data, novel analysis/modeling approaches, and convincing results of water–soil–vegetation interactions under …

Prestressed Concrete Inverted Tee Beams With Cfrp For Building Structures, Herish A. Hussein, Zia Razzaq

Civil & Environmental Engineering Faculty Publications

Presented herein is the outcome of a study of prestressed concrete inverted tee beams with carbon fiber reinforced polymer (CFRP) sheets for possible use in building structures. To determine an effective approach for the use of CFRP, nine different retrofitting schemes are investigated for a prestressed beam under quasi-static distributed load to increase flexural strength. The theoretical analysis is based on coupling moment-curvature relations with a central finitedifference formulation. Three different thicknesses of CFRP sheets are studied in both tension and compression and effective retrofitting schemes are identified.