Engineering Commons^™

Covid-19 And Traffic Safety: Exploring Exposure, Crash Frequency And Severity, And Roadway And Network Design, Nicholas N. Ferenchak Ph.D

Data

Early COVID-19 lockdowns in the first half of 2020 largely kept people at home, thereby reducing motor vehicle traffic levels. Theoretically, reduced traffic exposure should have resulted in reduced motor vehicle crashes. However, a variety of factors may have complicated this relationship. In order to better understand the impact of COVID-19 lockdowns on traffic safety outcomes, we explore fatalities, injuries, and total crashes before and during the lockdowns on both the national and state levels. We provide descriptive statistics and create negative binomial regressions exploring the role of vehicle, user, and built environment factors on traffic safety outcomes. Findings suggest …

Increasing Bridge Durability And Service Life With Lidar Enhanced Unmanned Aerial Systems (Uas), Fernando Moreu, Mahsa Sanei, Chris Lippitt

Publications

Bridge construction inspections require quantitative measurements and location information. The conventional approach is visual inspection, which in general, is rather time-consuming, expensive due to traffic closure, subjective, and needs special access. Therefore an automated rebar layout detection algorithm was developed to quickly extract quantitative rebar layout information from the LiDAR data. This systematic method can automatically cluster the bridge elements from a 3D point cloud by using LiDAR-equipped UAS data collection and unsupervised machine learning techniques. A new automated inspection system using a LIDAR-equipped UAS can eventually if developed and tested be more reliable as well as less expensive. In …

Krs And Kar Review Of Models As A Legal Contract Document, Bryan Gibson, Pam Clay-Young, Rachel Catchings, Chris Van Dyke

Kentucky Transportation Center Research Report

State departments of transportation (DOTs) are expanding the use of electronic engineering data (EED) throughout highway projects — from design and construction through asset management. Included under the umbrella of EED are technologies such as building information modelling (BIM), digital terrain models (DTMs), and 3D models and plan sets. The Kentucky Transportation Cabinet’s (KYTC) Digital Project Delivery (DPD) Initiative is spearheading the transition to EED in the state. While digital delivery promises to streamline project development and management it does not come without hurdles. This report discusses methods for agency wide implementation of EED and highlights best practices for managing, …

Inspection Of Flexible Fillers In Post-Tensioned Bridges, Carley Gonzalez

Doctoral Dissertations and Master's Theses

The Florida Department of Transportation (FDOT) is currently pushing toward the use of flexible fillers (FF) in new post-tensioned (PT) bridges. Flexible fillers have several advantages compared to the currently used cementitious grouts (CG) and can offer longer-lasting structures by providing better corrosion protection and allowing for replaceable tendons, which reduces the overall maintenance costs over the structure’s lifespan. Due to these fillers being used in new bridges, FDOT needs effective nondestructive evaluation (NDE) methods to employ in their biennial inspections. There are currently numerous NDE methods available to inspectors that have been used to identify defects in PT bridges …

A Snapshot Of Sars-Cov-2 In Wastewater Treatment Plants In Northwest Arkansas, Katie Loethen

Biological and Agricultural Engineering Undergraduate Honors Theses

Because SARS-CoV-2, a coronavirus, is released in the fecal shedding of covid-positive patients, the virus enters the municipal waste stream and flows to wastewater treatment plants (WWTPs). The goal of this research is to quantify the effectiveness of wastewater treatment processes at removing SARS-CoV-2 from wastewater and preventing its release into the environment. Sampling at Paul R. Noland and West Side WWTPs in Fayetteville, Arkansas, took place from August 2020 to May 2021, and samples were tested for the presence of SARS-CoV-2 using N1 and N2 primers via RT-qPCR. Sampling days which returned positive detection of one or both of …

Developing A Lagrangian Sediment Transport Model For Natural Streams, Saman Baharvand

Civil Engineering Dissertations - Archive

Sediment transport in natural streams is a complex process that can significantly affect the stream’s water quality, ecosystem, and morphology. Suspended sediment concentrations can adversely affect the health of the ecosystem and aquatic species, and the deposited sediment particles can change the morphology and have irreparable environmental impacts. Several numerical models that can be used to manage and mitigate the adverse effects of sediment released into rivers by natural or anthropogenic activities have been developed to estimate the sediment and pollutant transport in waterbodies. However, the goal of the research for this thesis was to develop a Lagrangian stochastic sediment …

Evaluation Of Decision-Making Prediction Models For Sewer Pipes Asset Management, Salar Shirkhanloo

Civil Engineering Dissertations - Archive

Wastewater collection systems deteriorate over time, requiring continuous adjustments and the development of asset management frameworks on the part of utility owners to maintain the performance of their assets. Any asset management framework should emphasize the importance of asset inspection and condition evaluation for efficient system operation and maintenance. Closed-circuit television (CCTV) is the most widely used tool in the United States for inspecting the interior of sewer pipes, which is a somewhat expensive and time-consuming process given the extensive inventory of pipes in a city. Due to their vast inventory of these pipes, no municipality can inspect every individual …

Implementation Of Secondary And Tertiary Treated Wastewater In Concrete Manufacturing, Amany G. Micheal Prof., Haidy Abdel Salam, Gouda Ghanem

Civil Engineering

Water scarcity is a problem that faces many regions. In a developing and arid country like Egypt, the need for freshwater is exponentially increasing. This research is an evaluation of the recycled wastewater to be used in concrete manufacturing. The treated wastewater is blended with potable water with percentages of 25%, 50%, and 100%. The mixture of the two types of water is used in concrete mixing and curing. Control specimens with pure potable water are cast for comparison. The setting time for Ordinary Portland Cement is tested using the different water mixes. The hardened concrete is tested in compression …

Disposable Puff Bar Electronic Cigarettes: Chemical Composition And Toxicity Of E-Liquids And A Synthetic Coolant, Esther E. Omaiye, Wentai Luo, Kevin J. Mcwhirter, James F. Pankow, Prue Talbot

Civil and Environmental Engineering Faculty Publications and Presentations

The popularity of disposable fourth-generation electronic cigarettes (ECs) among young adults and adolescents has been increasing since the ban on flavored cartridge EC products such as JUUL. Although the constituents and toxicity of some cartridge-based fourth-generation ECs, such as JUUL, have been studied, limited data exist for other disposable ECs such as Puff. The purpose of this study was to determine flavor chemicals, synthetic coolants, and nicotine concentrations in 16 disposable Puff devices, evaluate the cytotoxicity of the different flavors from the Puff brand using in vitro assays, and investigate the health risks of synthetic coolants in EC products. Gas …

A Heuristic For The Two-Echelon Multi-Period Multi-Product Location–Inventory Problem With Partial Facility Closing And Reopening, Puntipa Punyim, Ampol Karoonsoontawong, Avinash Unnikrishnan, Vatanavongs Ratanavaraha

Civil and Environmental Engineering Faculty Publications and Presentations

In this paper, the two-echelon multi-period multi-product location–inventory problem with partial facility closing and reopening is studied. For each product and period, plants serve warehouses, which serve consolidation hubs, which service customers with independent, normally distributed demands. The schedule of construction, temporary partial closing, and reopening of modular capacities of facilities, the continuous-review inventory control policies at warehouses, the allocation of customer demands to hubs, and the allocation of hubs to warehouses are determined. The service levels for stockout at warehouses during lead time and the violation of warehouse and hub capacities are explicitly considered. The proposed mixed-integer non-linear program …

Study And Comparison Of The Performance Of Steel Frames With Brb And Sma Bracing, Mohsen Jalalvandi, Ahmad Soraghi, Seyed Mohammadreza Farooghi Mehr, Abbas Haghollahi, Ali Abasi

Department of Civil and Environmental Engineering: Faculty Publications

Designing steel structures with Concentric Braced Frame (CBF) lateral systems has been common in recent decades. This type of bracing has a quite unstable and complicated behavior in relatively intense earthquakes. This study tries to improve the seismic behavior of steel frames with CBF braces equipped with Shape Memory Alloy (SMA) and Buckling Restrained Braces (BRBs). In this manner, a multi-story building with inverted V chevron bracing was considered. Nonlinear time-history analyses have been performed using OpenSEES software. The dynamic responses of frames with SMA and BRB braces were compared. The results showed that the SMA and BRB braces provide …

Modeling Triaxial Testing With Flexible Membrane To Investigate Effects Of Particle Size On Strength And Strain Properties Of Cohesionless Soil, Thang Pham, Md. Wasif Zaman, Thuy Vu

Civil Engineering Faculty Publications

A 3D DEM model using Particle Flow Code (PFC3D) software was developed utilizing a bonded-ball flexible membrane approach to study cohesionless soil as a discontinuous discrete material. This approach is not yet widely used because of its complexity and high computational cost, but it allowed the authors to observe the stress-strain curves of triaxial specimens, to single out effects of individual factors on the strength and strain properties, and to observe the formation of the shear band and failure surface. The 3D model was calibrated and verified with experimental data, and a sensitivity analysis was carried out for the microparameters. …

Wind Flow Characteristics Of Multi-Vortex Tornadoes And Their Wind Effects On Residential Houses, Yi Zhao

Doctoral Dissertations

"Tornadoes strike the USA very frequently, with an average of 1200 reports per year, and the average annual tornado-induced property loss has reached $10B. The devastation from recent tornadoes have prompted a renewed interest in better understanding tornado dynamics, their interactions with the built environment, and the performance of civil structures during tornadoes. In the past, the wind effects caused by single-vortex tornadoes have been widely studied, while the multi-vortex tornadoes were rarely considered. In fact, many previous deadly, costly tornadoes involved multiple vortices. Therefore, it is important to understand the wind flow characteristics of multi-vortex tornadoes in order to …

Innovative Foundation Alternative Inspired From Tree Roots, Macie Larranaga

Boise State University Theses and Dissertations

It is not easy to find a more efficient foundation system than the roots of a tree. Trees create a vast three-dimensional network of roots to support and anchor the critical above-ground trunks, leaves, and limbs. In this work, investigations are made for the feasibility of imitating such a technique and creating similar networks to support civil infrastructure, particularly those subjected to moment loads such as traffic signal posts. Some of the raised questions were: Is it feasible to have a shallow tree root-based foundation system to provide the same capacities as conventional foundation alternatives? If this is feasible: What …

Towards Sustainable Cities: Life Cycle Cost Analysis Of The Construction Of A Novel Wastewater Management System, Bibhas B. Tanmoy

Theses and Dissertations

Wastage of water is one of the most common environmental issues in the modern era. However, if this level of usage can be controlled, or recirculated properly, the wastage can be lowered down to a very minimum. In the conventional residential plumbing system, blackwater and greywater gets mixed and goes through the same sewage pipe. This mixture turns the whole wastewater amount into blackwater, which requires complex treatment before discharge. Greywater on the other hand can be discharged to waterbodies requiring almost zero treatment. In this study, a new wastewater management method is proposed where the plumbing system is split …

Tree Ring Reconstructions Of Streamflow For The Lower Rio Grande Valley Of Texas, Adedolapo Mutiyat Adeyanju

Theses and Dissertations

The Rio Grande River is a major water source for people living within the USA-Mexico border. The Rio Grande River has its headwaters in the San Juan Mountains in Colorado and the Sierra Madre Occidental in Mexico before flowing into Texas through El-Paso. The water supply issues facing the Lower Rio Grande Basin (LRGB) are extremely complex from international restrictions to severe climate change. The river shares its flow between the U.S.A and Mexico based on the provisions of the 1944 treaty between the U.S.A and Mexico. The LRGB flow is regulated by releases from Falcon and Amistad Reservoirs managed …

Tap Water Disinfection In The Electrochemical Precipitation Process By Using Novel Conductive Concrete, Md Shoriful Islam

Theses and Dissertations

Electrochemical precipitation (EP) is tested to learn about its impact on disinfectants in tap water. The EP process involves applying electricity through electrodes submerged in water to precipitate dissolved metals like water hardness out without chemical additives. In the study, tap water was tested to learn about EP’s impact on disinfectants. Tap water contains not only hardness but also residual disinfectants. It is very essential for the safety of drinking water against the potential ingress of pathogens before the water reaches the end-users. USEPA mandates that the free chlorine level in drinking water should be 0.2mg/L to 4 mg/L. …

Combining Passive And Active Ultrasonic Stress Wave Monitoring Techniques: Opportunities For Condition Evaluation Of Concrete Structures, Thomas Schumacher, Ernst Niederleithinger

Civil and Environmental Engineering Faculty Publications and Presentations

Concrete structures are invaluable assets to a society and managing them efficiently and effectively can be supported by information gathered through structural health monitoring (SHM). In this paper, a combined approach based on passive, i.e., acoustic emission (AE), and active, i.e., ultrasonic stress wave (USW) monitoring techniques for application to concrete structures is proposed and evaluated. While AE and USW are based on the same underlying physics, i.e., wave motion in solids, they differ fundamentally with respect to the nature of the source. For the former, external stimuli such as mechanical loads or temperature cause the rapid release of energy …

Effectiveness Assessment Of E-Ticketing Technology In Construction Of Transportation Projects, Sharareh Kermanshachi, Karthik Subramanya

Publications

The construction of highway infrastructure has devoted significant resources towards e-Construction to reduce the paperwork and automate the tasks in daily operations. Electronic Ticketing (e-Ticketing) is one such component of e-Construction that aids in the digital transfer of material tickets such as asphalt and concrete which accounts for more than fifty per cent of construction costs. Despite the benefits of e-Ticketing, many state departments and agencies are unwilling to transition into this technology. No studies have identified the cause of the delay in the implementation process, developed a framework to comprehend the platform's full potential, quantified savings, and suggested strategies …

Temporal Lidar Scanning In Quantifying Cumulative Rockfall Volume And Hazard Assessment: A Case Study At Southwestern Saudi Arabia, Abdullah A. Alotaibi, Norbert H. Maerz, Kenneth J. Boyko, Ahmed M. Youssef, Biswajeet Pradhan

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Rockfalls and unstable slopes pose a serious threat to people and property along roads/highways in the southwestern mountainous regions of Saudi Arabia. In this study, the application of terrestrial light detection and ranging (LiDAR) technology was applied aiming to propose a strategy to analyze and accurately depict the detection of rockfall changes, calculation of rockfall volume, and evaluate rockfall hazards along the Habs Road, Jazan Region, Saudi Arabia. A series of temporal LiDAR scans were acquired at three selected sites. Our results show that these three sites have different degrees of hazard due to their geological differences. The mean volume …

Airborne Contaminant Dispersal In Critical Built Environments, Arup Bhattacharya

All Dissertations

The Indoor Air Quality (IAQ), being one of the most significant exposures to human beings, encompasses the concepts of comfort and safety from unwanted contaminants. Whereas the thermal comfort is controlled through proper conditioning and distribution of ventilated air, controlling the airborne contaminants requires careful investigation of the flow characteristics. IAQ translates to different requirements, depending on the intended use of the indoor environment. In critical indoor spaces such as Operating Rooms and Cleanrooms, the principal focus of IAQ is to remove/contain/divert contaminants flowing with the airstream to maintain the required sterility, as contamination can lead to adverse patient/product outcomes. …

Use Of A Trial Function Method To Semi-Analytically Simulate Matrix Diffusion In Heterogeneous And Fractured Media, Kien Trung Pham

All Dissertations

A semi-analytic trial function model is applied to simulate matrix diffusion in systems of parallel fractures, 2-D/3-D discrete fracture networks, and in 3-D heterogeneous media. The trial function model gives low normalized root mean square error (NRMSE) when compared to the parallel fracture analytical solution over a range of fracture spacing, with considerations for retardation and decay. The semi-analytic trial function model is efficient in time and maintains less than 6% NRMSE when it simulates matrix diffusive transport in 2-D/3-D discrete fracture networks (DFN). The model can predict DFN plume within a few meters of accuracy compared to fine-grid DFN …

Influence Of Specimen Geometry And Anisotropy On Dynamic Modulus Of Asphalt Mixes In South Carolina, Srinivasan Nagarajan

All Dissertations

The objective of this study was to characterize the variability of dynamic modulus of asphalt mixes in South Carolina on the basis of geometry and anisotropy. High priority mixes Surface Type B, and C; Intermediate Type B and C and Base Type A from three different days of production were collected from seven different contractors each having a different aggregate source and the dynamic modulus was measured using the Asphalt Mixture Performance Tester (AMPT) at temperatures of 40, 70, 100 and 130℉ (4.4, 21.1, 37.8, and 54.4℃) and at frequencies of 25, 10, 5, 1, 0.5, and 0.1 Hz. One-way …

Integration Of Techno-Economic Analysis (Tea) And Life Cycle Assessment (Lca) For Sustainable Process Design, Roksana Mahmud

All Dissertations

For sustainable design, technology developers need to consider not only technical and economic aspects but also potential environmental impacts while developing new technologies. Techno-economic analysis (TEA) evaluates the technical performance and economic feasibility of a technology. Life cycle assessment (LCA) evaluates the potential environmental impacts associated with a product system throughout its life cycle from raw material extraction to disposal. Generally, TEA and LCA are performed separately for technology assessment. Understanding of the trade-off between economic and environmental performances is crucial for sustainable process design, which is not fully available if TEA and LCA is performed separately. In contrast, integration …

Tessellated Structural-Architectural Systems: Experimental Testing And Interdisciplinary Student Projects, Grace F. Crocker

All Dissertations

This dissertation discusses a new structural system called a Tessellated Structural-Architectural (TeSA) system. These TeSA systems utilize architecturally appealing tessellations in load-bearing structures comprised of interlocking tiles in a pattern. This dissertation focuses on the design, construction, and structural behavior of these TeSA systems, as well as their value as an interdisciplinary learning tool.

This dissertation has 4 research objectives: 1) Demonstrate the fabrication and construction of a precast reinforced concrete (RC) TeSA shear wall system; 2) Measure the structural performance of the RC TeSA shear wall system; 3) Compare simplified shear and flexural analysis methods for RC TeSA shear …

Development Of Distress Index Prediction Models For Rehabilitation Treatments In Louisiana Using Advanced Machine Learning Techniques, Momen R. Mousa, Marwa Hassan

Publications

Performance prediction models are used by state agencies to predict future trends in distress indices, hence, determining the required maintenance and/or rehabilitation treatment as well as the deterioration rate and remaining pavement service life. However, most of these models are based on a limited number of parameters and cannot predict the performance distress indices reliably. Such limitation resulted in having, most of the time, a maximum prediction period of five years. As a solution and coping with the ever-increasing size of pavement data, machine learning techniques have become a promising alternative. The objective of this study was to develop a …

Using Rice Husk Ash (Rha) As Stabilizing Agent For Problematic Subgrade Soils And Embankments, Zahid Hossain, Rifat Bulut, Fares Tarhuni, Hussein Al-Dakheeli

Publications

Arkansas produces the most of the rice in the United States. About 20% of poddy is rice husk (RH), which is burnt under controlled conditions to produce rice rusk ash (RHA). The RHA is considered an environmental hazard and a significant challenge for rice millers. However, RHA is rich in pozzolanic material, which is mainly silica. In this study, RHA is used to stabilize poor soils. Another commonly used stabilizer, hydrated lime (HL), has also been evaluated for comparison purposes. Thus, this study aimed to determine the optimum percentages of RHA, HL, or a combination of these two agents by …

A Deep Learning Tool For The Assessment Of Pavement Smoothness And Aggregate Segregation During Construction, Mostafa Elseifi, Ramchandra Paudel, Md Tanvir Ahmed Sarkar, Hossam Abohamer, Nirmal Dhakal

Publications

Pavement construction monitoring and quality assurance (QA) practices are mostly based on costly, discrete, and destructive methods. Most quality assurance programs are based on pavement construction procedures encompassing in-situ coring for layer thickness determination, density measurements, laboratory testing to measure volumetric properties, and smoothness measurements in case of the availability of a profiler. The main objective of this study was to develop a machine learning-based classifier for predicting pavement roughness and aggregate segregation based on digital image analysis, image recognition, and deep learning machine models. The developed Convolution Neural Networks (CNN) models were trained, tested, and validated using 600-pavement surface …

Development Of Balanced Mix Design Quality Control Specifications Based On The Acceptance Limits Of Hma Performance Tests, Lucas Tameirao Abrantes

Open Access Theses & Dissertations

With the augmented use of recycled materials, recycling agents, modified binders, andwarm mix asphalt additives, several highway agencies including the Texas Department of Transportation (TxDOT), have considered methods to improve the durability and long-term performance of asphalt concrete (AC) mixes. The need for performance tests that could consistently evaluate the rutting and cracking potentials of AC mixes became crucial as the popularity of the Balanced Mix Design (BMD) concept has increased over the years. A concern now is related to the practicality of these tests for routine use in the process of quality control and quality assurance during the field …

Using Computational Fluid Dynamics To Predict Flow Through The West Crack Breach Of The Great Salt Lake Railroad Causeway, Michael Rasmussen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Great Salt Lake in Utah, USA, is a terminal, saline lake and is divided into two primary sections (northern and southern) by an east-to-west railroad causeway. Shortly after completion of the earth-fill causeway in the late 1950s, the two sections became dramatically different with differences in water surface elevation and water density. These differences cause the formation of a unique flow behavior commonly referred to as a density-driven exchange flow or bi-directional flow; a behavior observed in other lake and ocean settings where two fluids of differing densities interact. Measuring these exchange flows is a priority for lake managers …