Engineering Commons^™

Reliability Of Sfrp-Strengthened Rc Bridge Columns Subjected To Blast Loads, Ahmad Alsendi, Christopher D. Eamon

Civil and Environmental Engineering Faculty Research Publications

The reliability of reinforced concrete bridge columns strengthened with externally bonded, steel-fiber reinforced polymer fabric subjected to blast loads was investigated. Columns were modeled with a nonlinear finite element approach that considers material damage, fracture, and separation. Different concrete strengths, longitudinal reinforcement ratios, and gravity and blast load levels were considered, while uncertainties in material strength and stiffness parameters, as well as load characteristics, were incorporated in the probabilistic analysis. It was found that the use of SFRP can allow significant increases in blast load while maintaining the same level of column reliability.

Examination Of The Correlation Between Shear Strength, California Bearing Ratio, And Index Properties Of Fine-Grained Soil, Billy W. Rushema

Master of Science in Civil Engineering Theses

Abstract

California Bering Ratio (CBR) is used to evaluate the strength of the pavement materials by comparing bearing capacity of the material with that of a high-quality crushed stone. This test adopted by transportation agencies and widely used in the design and analysis of pavement. Several agencies developed design thickness chart based on the CBR values of the subgrade. However, CBR test is time consuming and expensive to perform compared to shear strength test and therefore several studies have been conducted to establish correlation between shear strength and CBR. The published correlation models between CBR and shear strength of soil …

International Analysis On The Traffic Impact Of The Covid-19 Pandemic, Fanny Margaretha Kristiansson

Doctoral Dissertations and Master's Theses

The purpose of this research was to assess, compare, and contrast the impact of COVID-19 activity restrictions on road-based transportation activity in regions of the US, Sweden, and China from January 1st to December 31st, 2020. Roadway traffic volumes were used to relate the progression of reported COVID-19 cases and government directives for social separation in three countries with diverse governmental responses.

Among the contributions of this paper was the illustration of the timeline and level of public responses to closures, lockdowns, and reopening as represented through rapid traffic decreases and increases. Traffic was greatly impacted, showing that the pandemic …

Unveiling Women’S Needs And Expectations As Users Of Bike Sharing Services: The H2020 Diamond Project, Andrea Gorrini, Rawad Choubassi, Federico Messa, Wafaa Saleh, Augustus Ababio-Donkor, Maria Chiara Leva, Lorraine D'Arcy, Francesco Fabbri, David Laniado, Pablo Aragon

Articles

Within the objectives of the H2020 DIAMOND project, the paper investigates women’s needs and expectations as users of the bike-sharing service managed by Syndicat Mixte Autolib et Velib Métropole in the territory of Paris Region-Petite Couronne (France). The paper presents a thematic literature review focused on gender inclusion in bike-sharing schemes. The proposed methodological approach is based on (i) Geographic Information Systems for the analysis of geolocated open datasets related to land, sociodemographic and mobility characteristics of the areas surrounding each docking stations. This was aimed at identifying a short list of suitable bike-sharing docking stations, which were further characterized …

Comparison Of The Resistance Of Belitic Calcium Sulfoaluminate Cement And Portland Cement To Sulfate Attack And Sulfuric Acid, Rilye Dillard

Graduate Theses and Dissertations

Microbially induced corrosion (MIC) is a fairly common concrete deterioration mechanism with many negative effects. MIC is a complex chemical and biological process that occurs in sewage systems and is nearly impossible to replicate in a laboratory setting. For this study, sulfate and sulfuric acid attack on concrete were studied to mimic two stages of the MIC process. The ASTM C1012, Standard Test Method for Length Change of Hydraulic-Cement Mortars Exposed to a Sulfate Solution and a modified ASTM C1012 accelerated method were used to compare the sulfate resistance of belitic calcium sulfoaluminate (BCSA) cement, portland cement (PC), and PC-fly …

Development Of An Ultraviolet Absorbance Assay To Estimate Air Entrainer Dosing For Concrete Containing Fly Ash, James Spencer

Graduate Theses and Dissertations

Fly ash is a coal combustion byproduct that can be used as a supplementary cementitious material (SCM) in concrete, offering benefits such as increased workability, durability, and strength. Fly ash can be used as a partial replacement to cement, reducing concrete productions costs and decreasing disposal in landfills. However, variability of fly ash properties (e.g., carbon content, adsorption site density) confounds estimates of the air entraining admixture (AEA) dose needed to achieve a specified air content in concrete. Air entrainment is needed to improve freeze-thaw resistance and limit concrete cracking. The foam index (FI) test is currently used to estimate …

Field Demonstration Of Gpr And Uav Technologies For Evaluation Of Two Us 75/77 Bridges, Sepehr Pashoutani, Jinying Zhu, Chungwook Sim, Ji-Yong Lee

Nebraska Department of Transportation: Research Reports

Two Nebraska bridges with asphalt overlay were selected for nondestructive testing and evaluation (NDT/NDE). Three NDT techniques were conducted on these two bridges, including Ground Penetrating Radar (GPR), Half-Cell Potential (HCP) and Unmanned Aerial Vehicle (UAV) imaging. NDT data were collected during three construction stages of the bridges: (1) before repair on existing asphalt overlay; (2) on bare concrete after asphalt removal; (3) and after repairing delaminated concrete.

A machine learning technique, autoencoder, was used to build quantitative relationships between different NDT datasets. On bare concrete, the GPR amplitude and HCP voltage show a strong linear relationship. Then a threshold …

Improving Logistics Efficiency Through Collaborative Truck Routing, Patrick Dougherty

Industrial Engineering Undergraduate Honors Theses

The logistics industry is among the world’s largest and most essential. Specifically, trucking is a massive component of the modern logistics system. In 2012, truck transportation carried 68% of all freight tonnage in the U.S. However, trucking currently faces significant problems with efficiency and sustainability. Of all miles driven by trucks yearly in the U.S., 25% are driven with empty loads and 36% are driven with underutilized loads. In addition to this economic inefficiency, the industry faces social and environmental challenges. Driver turnover rates are near 100%, and trucking accounts for a significant level of greenhouse gas emissions. One potential …

Analysis, Modeling, And Simulation (Ams) Case Studies Of Connected And Automated Vehicle (Cav) Implementations Specific To The South Central Region, Christopher Melson, Jiaqi Ma

Data

Connected and automated vehicles (CAVs) offer potentially transformative and far-reaching impacts to the transportation system. However, realized benefits will be directly tied to how well agencies prepare for these technologies. This report documents efforts that support CAV preparatory actions in Louisiana and includes: (1) conducting a stakeholder survey to inform engagement activities to develop strategic partnerships in CAV deployment and (2) conducting crash analyses for deployment scenarios of CAV-based queue warning systems (QWSs).

An electronic survey was developed and disseminated to 273 Louisiana organizations. The purpose of the survey was to engage these organizations under the context of CAV planning …

Analysis Of Shear-Strength In Weathered Shale Strata Along A Highway Slope Failure Site In Northwest Arkansas, Olivia Overton

Civil Engineering Undergraduate Honors Theses

Slope failures cost millions of dollars per year to repair and can be deadly. Accurate modeling of slope conditions, including soil parameters, water table locations, and depth to bedrock, are essential to determining the overall stability of a slope. This project is a continuation of the work completed in 2019 by a former University of Arkansas researcher, Vanessa LeBow. LeBow RocScience used Slide2 modeling software to model two highway embankment slopes in Northwest Arkansas that experienced slope movement to determine whether increased use of geophysical data could increase the accuracy of slope stability models. A parametric study of shear strengths …

Cross Domain Iw Threats To Sof Maritime Missions: Implications For U.S. Sof, Gary C. Kessler, Diane M. Zorri

Publications

As cyber vulnerabilities proliferate with the expansion of connected devices, wherein security is often forsaken for ease of use, Special Operations Forces (SOF) cannot escape the obvious, massive risk that they are assuming by incorporating emerging technologies into their toolkits. This is especially true in the maritime sector where SOF operates nearshore in littoral zones. As SOF—in support to the U.S. Navy— increasingly operate in these contested maritime environments, they will gradually encounter more hostile actors looking to exploit digital vulnerabilities. As such, this monograph comes at a perfect time as the world becomes more interconnected but also more vulnerable.

Feasibility Study: Alternatives To Prevent Settlements And Bumps At Bridge Approach, Seunghee Kim, Jongwan Eun, Yusuf Alhowaidi, Daniel Robertson

Nebraska Department of Transportation: Research Reports

This project aims to examine the feasibility of improving the current design practice of the approach slab foundation in Nebraska and the alternative of using geosynthetic reinforcement of soils to prevent the bump issues near the end of bridge approaches via an in-depth numerical simulation study. A large-scale pullout test is also conducted as complementary to provide input parameters for the interaction between the regional soil and selected geosynthetics. Based on the results, it is recommended that the number of grade beam piles could be reduced to 40-50 % of the total number of abutment piles while maintaining the same …

Evaluating Asct Operations For Dodge Street Corridor, Anuj Sharma, Subhadipto Poddar, Atousa Zarindast, Christopher Day

Nebraska Department of Transportation: Research Reports

As Adaptive Traffic Control (ATC) is increasingly being implemented by various traffic agencies, careful evaluation is needed of the degree to which a given ATC implementation improves traffic signal performance. The present study details the evaluation of ATC for two arterial corridors in the City of Omaha, Nebraska. Several performance measures were used across two stages of ATC implementation as well as during the unanticipated COVID-19 lockdown stage.

The average travel time and variability in travel time showed that Stage 1 of ATC implementation in Omaha did not improve traffic signal performance for the study’s main corridor, Dodge Street. This …

Project Management Research Support, Bryan Gibson, Jeff Jasper, Robin Baskette, Christopher Van Dyke, Doug Kreis

Kentucky Transportation Center Research Report

Like many state transportation agencies, the Kentucky Transportation Cabinet (KYTC) faces unprecedented challenges related to project development and management. Staff losses due to attrition and retirements have resulted in the loss of institutional knowledge. Early- to mid-career project managers (PMs) shoulder more responsibilities than ever while being expected to deliver over 600 successful projects each year. To improve the efficiency of project management, PMs must be able to access effective project management concepts, tools, and strategies which are field validated. Recognizing the importance of strengthening its project management capabilities, the Cabinet asked the Kentucky Transportation Center (KTC) to provide ongoing …

A Spatial Analysis Of Supply-Demand Of Public Transportation In Jefferson County, Kentucky., Nastaran Abdoli

Electronic Theses and Dissertations

Public transportation is important as it serves individuals, especially the transit-dependent population, by providing a basic mobility service to these people and all others who rely on public transportation. This research utilized estimating public transportation demand and supply to analyze the spatial patterns of public transportation in Jefferson County, Kentucky. The study focuses on the transit-dependent population, and it considers indicators of age, poverty status, vehicle ownership, and foreign-born population with less than five years residency in the United States. This study conducted a public transit supply-demand analysis to identify areas with imbalanced supply and demand in Jefferson County at …

Impact Of Covid-19 On City Streets, Mihir Sharma

Honors Scholar Theses

Covid-19 has had a severe impact on the urban fabric of many cities and caused disruption to the current way of living. This paper attempts to shed light on the impact that Covid-19 has had on the city streets and how city streets have adapted to the disruptions brought on by the virus. Furthermore the paper lays down recommendations that cities can use to make their streets healthier and safer

Analysis, Modeling, And Simulation (Ams) Case Studies Of Connected And Automated Vehicle (Cav) Implementations Specific To The South Central Region, Christopher Melson, Jiaqi Ma

Publications

Connected and automated vehicles (CAVs) offer potentially transformative and far-reaching impacts to the transportation system. However, realized benefits will be directly tied to how well agencies prepare for these technologies. This report documents efforts that support CAV preparatory actions in Louisiana and includes: (1) conducting a stakeholder survey to inform engagement activities to develop strategic partnerships in CAV deployment and (2) conducting crash analyses for deployment scenarios of CAV-based queue warning systems (QWSs).

An electronic survey was developed and disseminated to 273 Louisiana organizations. The purpose of the survey was to engage these organizations under the context of CAV planning …

Supporting Transportation System Management And Operations Using Internet Of Things Technology, Hong Yang, Yuzhong Shen, Mecit Cetin, Zhenyu Wang

Computational Modeling & Simulation Engineering Faculty Publications

Low power wide-area network (LPWAN) technology aims to provide long range and low power wireless communication. It can serve as an alternative technology for data transmissions in many application scenarios (e.g., parking monitoring and remote flood sensing). In order to explore its feasibility in transportation systems, this project conducted a review of relevant literature to understand the current status of LPWAN applications. An online survey that targeted professionals concerned with transportation was also developed to elicit input about their experiences in using LPWAN technology for their projects. The literature review and survey results showed that LPWAN’s application in the U.S. …

Going Green: A Comparative Analysis Of Green Urbanism In Paris And Shanghai, Jeanne Torp

Honors Theses

As climate change becomes more pressing with each day and as we scramble to slow down the challenges it poses, adapting the means of operation within our cities will become an invaluable tool for reducing humanity’s carbon footprint. This paper seeks to study the ways in which green infrastructure in global cities can be used to do just that—adapting to and mitigating the effects of challenges resulting from climate change. In order to provide a broad overview of the effectiveness of such green infrastructure systems across the globe, this research will focus on two cities that vary greatly in their …

Fatal Crashes At Highway Rail Grade Crossings: A U.S. Based Study, Subasish Das, Xiaoqiang Kong, Steven M. Lavrenz, Lingtao Wu, Mohammad Jalayer

Henry M. Rowan College of Engineering Departmental Research

Crashes at highway rail grade crossings (HRGCs) are often involved with fatalities due to the momentum of a train. This study collected nine years (2010–2018) of fatal HRGC crashes from the Fatality Analysis Reporting System (FARS) to perform the analysis. The Taxicab Correspondence Analysis (TCA) was applied to this dataset. This method identified several patterns that trigger HRGC-related fatal crashes. The findings indicate that fatal crashes involving multiple fatalities are often highly associated with alcohol-influenced drivers, poor lighting conditions, and inclement weather. The fatal crash that occurs during the daylight with the uninfluenced driver is less likely to involve more …

Abrasion Resistance Of Ultra-High-Performance Concrete For Railway Sleepers, Ariful Hasnat, Nader Ghafoori

Civil and Environmental Engineering and Construction Faculty Research

This study aimed to determine the abrasion resistance of ultra-high-performance concretes (UHPCs) for railway sleepers. Test samples were made with different cementitious material combinations and varying steel fiber contents and shapes, using conventional fine aggregate. A total of 25 UHPCs and two high-strength concretes (HSCs) were selected to evaluate their depth of wear and bulk properties. The results of the coefficient of variation (CV), relative gain in abrasion, and abrasion index of the studied UHPCs were also obtained and discussed. Furthermore, a comparison was made on the resistance to wear of the selected UHPCs with those of the HSCs typically …

A Methodology For Estimating Capacity And Passenger Car Equivalents For Connected And Automated Vehicles Traveling On Freeways, Antonio Hurtado Beltran

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Recently, there has been a significant amount of research related to heavy trucks operating as connected and autonomous vehicles (CAVs). In order to understand the potential impact on the freeway system of CAV technologies, analyses should be conducted using the standard US methodological framework. In the current version of the Highway Capacity Manual (HCM-6), equal-capacity passenger car equivalencies (EC-PCEs) are used to account for the effect of heavy trucks on capacity and quality of service analyses. It is argued in this dissertation the HCM-6 EC-PCE methodology for basic freeway and multilane highway segments can be used to explore a wide …

Nighttime Pedestrian Fatalities Across The United States And Their Relationship With Built Environment And Socioeconomic Factors: Gis-Based Analysis And Assessment, Amir Tarighi

Civil Engineering ETDs

Fatalities from motor vehicle collisions are the fifth leading cause of years of lost life worldwide (Foreman et al., 2018) and are a great concern for all communities. This road safety crisis has been especially pronounced for U.S. pedestrians over the last decade. National records show that between 2010 and 2019, pedestrian fatalities in the U.S. increased 44% while all other traffic fatalities increased only 4% and more than fifty percent of pedestrian fatalities occurred in dark lighting conditions. This study analyzed the relationship between pedestrian fatality locations at night and five demographic characteristics of those locations including population density, …

Modeling Bus Bunching And Anti-Bunching Control Accounting For Signal Control And Passenger Swapping Behavior, Qi Xin, Rui Fu, Shaowei Yu, Satish V. Ukkusuri, Rui Jiang

Journal of Public Transportation

The conventional bus propagation process has two main shortcomings: one is bus bunching, the other is extra energy consumption by idling at signalized intersection and unexpected speed variation along the route. To overcome these problems simultaneously, an extended bus propagation model and an anti-bunching control are proposed. To extend the time-based bus propagation model, we employ finite state machine and intelligent driver model to establish a spatial-temporal based bus propagation model accounting for bus dynamic motion and passenger swapping behavior between bunching buses. To mitigate bus bunching and improve bus fuel economy in a cyber-traffic environment, an anticipated average speed …

Evaluation Of Permanent Concrete Barriers To Mash 2016, Samuel Elias Hovde

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

The objective of this research project was to develop evaluation criteria for permanent concrete barriers to MASH 2016 TL-3 and TL-4 without crash testing and then to evaluate permanent concrete barrier standards provided by the sponsoring agencies of the Midwest Pooled Fund Program. A literature review was conducted to determine evaluation criteria for stability, shape, strength, and anchorage, and a database of permanent concrete barrier crash tests was compiled. A survey was conducted to collect barrier standards from the members of the Midwest Pooled Fund Program, and barriers were selected and evaluated according to the determined methodology. A total of …

Intersection Redesign For Network Resilience And Safety, Antonio Pratelli, Pietro Leandri, Rosaria Aiello, Reginald R. Souleyrette

Civil Engineering Faculty Publications

This paper describes a procedure for improving the resilience of roadway networks. A methodology is outlined that develops a time-dependent and performance-based resilience index. This methodology was applied to an Italian road, with the aim of optimizing intersections that are critical due to inadequate baseline capacity. The methodology uses a calibrated microscopic traffic model (using Aimsun™) whereby average delay at intersection approaches are estimated by an analytical model. From the simulation, average speed over time is obtained for each approach. These values in turn are used as inputs for calculating each intersection’s resilience index. The procedure allows the identification of …

Laboratory Evaluation Of Geogrid-Reinforced Flexible Pavements, Mohammad Reza Sharbaf, Nader Ghafoori

Civil and Environmental Engineering and Construction Faculty Research

This study assessed the effectiveness of flexible pavements reinforced with two types of punched and drawn geogrids to reduce roadway base course thickness. Six laboratory tests were conducted using a steel cylindrical mold. Instrumentation included pressure cells placed at various locations of the test sections and a linear variable differential transformer which was placed on top of the loading system. A hydraulic actuator provided 40 kN (9 kips) cyclic load through a 305 mm (12 in) circular steel plate at a frequency of 0.77 Hz. Test results revealed that inclusion of both geogrid types in flexible pavement showed reductions in …

Distributionally Robust Optimization Utilizing Facility Location Problems, Elijah Kling

Civil and Environmental Engineering Undergraduate Honors Theses

Facility location problems are used in widespread application in transportation, freight, supply chain, and logistics problems. Models can be developed as deterministic, where all parameters are known, or robust, where a parameter has uncertainty. This thesis explores a new method for developing robust formulation and compares the implications of assuming values for this uncertain parameter. Two models are solved, and both are compared against their deterministic counterparts using numerical analysis. By manipulating the input parameters and considering real world implications of the solutions, either the robust or deterministic can show better performance.

Biopolymerized Slope/Subgrade Stabilization And Advanced Field Monitoring, Chung R. Song, Layla Bitar, Richard L. Wood, Yong-Rak Kim, Jongwan Eun, Binyam M. Bekele, Basil Abualshar

Nebraska Department of Transportation: Research Reports

The slightly overconsolidated glacial tills and weathered shales in Midwestern states of the USA often show substantial strength degradation after construction. This strength reduction often causes time dependent slope failures along the roadside. This study investigated the possibility of applying biopolymer based soil modification techniques to mitigate the strength reduction phenomenon of these soils. For this research, several different biopolymers were evaluated through laboratory tests, two biopolymers were selected for extensive weathering tests, then a higher-performing biopolymer, Xanthan, was applied to a test slope in Verdigre, Nebraska with heavy instrumentation. The followings are the summary of the results.

The unweathered …

Maximum Coverage Facility Location Drone Routing Problem With Multiple Trip Stops, Marie Roza

Civil and Environmental Engineering Undergraduate Honors Theses

Integer linear optimization can be used to formulate routing problems as models to find optimal solutions given a set of inputs and constraints. In this research, Chauhan et al.'s publication, "Maximum coverage capacitated facility location problem with range constrained drones," is expanded upon by modeling a facility location problem with two-to-one drone deliveries. The model analyzes a set of potential facilities that are available to meet the demands of a set of demand points. The drone delivery routes are modeled with the assumption that each opened facility is assigned one drone that can fulfill up to two demand points’ demands …