Civil and Environmental Engineering Commons^™

Analysis Of Loading Rate, Fiber Orientation And Material Composition Through Image Processing And Digital Volume Correlation In High Performance Concrete, Aidan R. Carlson

Electronic Theses and Dissertations

Ultra High Performance Concrete (UHPC) and High Performance concrete (HPC) is characterized by high compressive strength and high toughness. This is achieved through maximizing the particle packing density in the matrix and the use of fibers to reinforce the matrix, increasing the materials toughness. The interactions of fibers and the matrix during loading is quite complex and involves several different energy dissipation mechanisms. The goal of this work and this thesis is to investigate these interactions and identify any changes in material response, and hope that these changes may be useful for the design of UHPC moving forward.

In this …

Examining The Impact Of Centerline Rumble-Strip Installation In Prevention Of Head-On And Opposite Sideswipe Collisions In Maine, Jhan Kevin Gil Marin

Electronic Theses and Dissertations

Among all traffic collisions, lane departure crashes are the leading type of serious traffic crashes in Maine, comprising 72% of state-wide traffic fatalities. To reduce these crashes, Maine Department of Transportation (MaineDOT) installed shoulder and centerline rumble strips on roadways to prevent lane departure crashes in Maine. With a total installed length of 1503 miles of rumble strips, specifically 511 miles of centerline rumble strips in bidirectional and undivided rural two-lane roadways, there is a need to understand the impact of rumble strips in reducing lane departure crashes. In this thesis, observational before-after studies with two methods: comparison group, and …

Using Probe Data To Understand The Impact Of The Covid-19 Pandemic On Roadway Safety, Ennis W. Marshall

Electronic Theses and Dissertations

Following the onset of the COVID-19 pandemic there was an observed decrease in traffic safety in the United Sates. New England was no exception to this, with traffic fatality rates increasing in Maine and Connecticut. This increase was attributed to the possibility that drivers had more opportunities to speed following the implementation of COVID-19 stay-at-home orders on roads with drastically reduced volume and decreased speed enforcement. To determine the state of research into the pandemic's effect on traffic safety around the world, an extensive critical review was conducted. The reviewed studies showed that roadways did indeed become less safe with …

Quantifying Impacts Of Climate Change On Headwater Streamflow Regime In Robinson Forest: Insights From 35-Years Of Data Collection., Lauren Brown

Electronic Theses and Dissertations

Climate change may shift patterns of streamflow permanence in headwater systems by altering the frequency, magnitude, duration, timing, and rate of change of surface streamflow, impacting both local ecosystems as well as regional water budgets and availability. While much uncertainty surrounds modeling-based methods to quantify the impacts of climate change on water budgets, long-term hydrologic data collected from headwaters in experimental research forests serve as critical evidence to reduce such uncertainty. The objective of this study is to quantify shifts in frequency, magnitude, duration, timing, and rate of change of streamflow in two headwater catchments with relatively little recent disturbance …

Wave Attenuation Through Submerged Oyster Aquaculture Cages, Liam T. Hanley

Electronic Theses and Dissertations

Coastal erosion presents a growing issue to shorelines around the world and is especially harmful to Maine, a region where sea-level rise is higher than the global average. Green and hybrid coastal defense strategies are being implemented around the country to provide sustainable, habitat-friendly solutions to erosion control. Maine is a hotspot for commercial aquaculture, with an estimated $13.6 million economic impact. This study looks to bridge the gap between Maine aquaculture and the living shorelines initiative, by determining the wave attenuating properties of submerged oyster cages. The project will be able to inform local oyster farmers, resource planners, and …

Investigating The Effect Of Bead Geometry On Fiber Orientation And Thermomechanical Properties For Large-Format Extrusion-Based Additive Manufacturing, Joanna F. Keaton

Electronic Theses and Dissertations

In large-format extrusion-based additive manufacturing of polymer composites, the relationship between material properties and processing parameters requires further investigation. This thesis focuses on the relationship between fiber orientation and thermomechanical properties for short fiber-filled thermoplastic polymer systems manufactured by extrusion-based additive manufacturing. Fiber orientation is particularly important in determining the thermomechanical properties of the composite material as properties in the direction of deposition are expected to be higher for highly aligned fibers than randomly aligned fibers. Fiber orientation distribution, which is related to processing parameters and deposition conditions, can be efficiently represented by the orientation tensor. The orientation tensor can …

Changes To Water Quality And Discharge In An Urban Stream In Southwest Jefferson County., Karina Henson

Electronic Theses and Dissertations

Mill Creek is the largest watershed in Southwest Jefferson County, where thousands of people live and work. Streams in the watershed have historically been channelized and altered to promote drainage, and stream health is of major concern. Louisville MSD is currently developing a watershed plan for Mill Creek by seeking understanding of current stream conditions. This paper will focus on historical trends in stream discharge and water quality. Peak and daily discharge, dissolved oxygen, specific conductance, and temperature data from USGS gages at Mill Creek and the Mill Creek Cutoff was analyzed to understand how water quality and flow rates …

Experimental Study On The Behaviour Of A Magnetorheological (Mr) Damper And Evaluation Of Numerical Models, Shelair Sinjari

Electronic Theses and Dissertations

MR dampers are smart dampers that improve structural performance through vibration control. Vibration of tall or flexible structures and structural elements induced by dynamic loads such as wind and earthquakes can cause severe damage to the structure and discomfort for individuals. Therefore, dampers are commonly installed to increase the energy dissipation capacity and mitigate large amplitude vibrations. MR dampers are gaining recognition because of the unique rheological properties offered by the magnetically sensitive MR fluid. Changes to the current level, along with the frequency and amplitude of vibration, affect the force-displacement and force-velocity hysteresis relationship and thus the amount of …

Canadian Automotive Recycling Industry: Developing Towards A Circular Economy, Simon Che-Wen Tseng

Electronic Theses and Dissertations

The Canadian automotive recycling industry is essential to the modern world market to properly dispose of the millions of obsolete vehicles annually. Currently, the industry is fragmented with mostly small to medium-sized operations. There is a lack of enforceable regulations specific to the automotive recycling industry for most jurisdictions. Conversely, the automotive manufacturing industry has embraced the idea of efficiency improvements toward a circular economy (CE). As an integral part of the automotive industry, the automotive recycling industry is a critical but often unseen contributor to a sustainable global industry. As such, the evolution of the Canadian end-of-life vehicle (ELV) …

Efficient Sintering Of Lunar Soil Using Concentrated Sunlight, Diprajit Biswas

Electronic Theses and Dissertations

Construction material is one crucial need for long-term habitation on the moon. When concentrated for high heat flux, solar radiation can heat lunar soil or regolith until it sinters at temperatures above 900°C. The solid, sintered soil simulant can be used as construction material. This work explores the conditions leading to effective lunar soil sintering for both direct and indirect irradiated sintering. Lunar soil simulants were sintered using concentrated light from a xenon-arc lamp with varying heat flux intensity. During direct sintering of LHS-1, a sintering range of 860°C-1140°C corresponding to a peak heat flux of 105-120 kW/m2 was identified …

Mechanics And Mechanisms Of Fracture For An Eastern Spruce Subject To Transverse Loading Using Acoustic Emission, Parinaz Belalpour Dastjerdi

Electronic Theses and Dissertations

Due to its excellent structural qualities and accessibility, wood is among the most often utilized structural materials. Despite its ubiquity, wood poses numerous challenges. It is heterogeneous and anisotropic. It has a complex hierarchical ultrastructure, and the properties can have wide variation within a species, and indeed within an individual tree. This work aims to improve our understanding of the strength and fracture behavior of spruce-pine-fir (south) (SPFs), particularly in cross-grain direction. This study’s primary goal is to examine the relationship between crack propagation and cross grain morphology under the following loading configurations: compact tension, compression, and rolling shear. The …

Performance Of Helical Piles Retrofitted With A Novel Collar Vane Under Lateral And Torsional Loads, Juan Sebastian Carvajal Munoz

Electronic Theses and Dissertations

Helical piles are lightweight deep foundations designed to support both compressive and uplift loads by mobilizing the shear strength of soil adjacent to helical plates that are welded to an extendable shaft. Helical piles are relatively inexpensive, can be installed quickly utilizing non-specialized equipment, and they are suitable for a wide range of soil conditions. However, helical piles are precluded from many applications due to their inability to support substantial lateral and torsional loads. To overcome this limitation, a novel easy-to-install Collar Vane is implemented to augment the lateral and torsional capacity of helical piles.

The Collar Vane consists of …

Durability Of Large-Scale 3d Printed Materials For Transportation Infrastructure, Felipe Saavedra

Electronic Theses and Dissertations

Large-format extrusion-based polymer Additive Manufacturing (AM) or 3D printing has been used for transportation infrastructure applications, including culvert outlet diffusers and precast concrete formwork. This research assesses thermoplastic composite material system durability and dimensional stability under different environmental exposure conditions. Accelerated exposure in the laboratory was conducted for moisture absorption, freeze-thaw cycles, and ultraviolet (UV) weathering. Specifically, this thesis investigates the use of bio-based renewable polymer composites for transportation infrastructure applications by correlating accelerated laboratory durability tests with site-specific environmental durability for selected applications. The thesis compares the performance of bio-based composite materials, wood fiber/ polylactic acid (WF/PLA), wood fiber/amorphous …

Laboratory Study Of Conditions Influencing Binder Formation And Co2 Sequestration During Carbonation With Hydrated Lime, Temitope Omokinde

Electronic Theses and Dissertations

The production of lime and cement used as additives in the chemical stabilization of soil emits 9% of the total CO2 emissions. The utilization of lime in soil carbonation has a potential for soil improvement via the formation of calcium carbonate and also helps in the sequestration of an appreciable percentage of the process-related CO2 (67% of the total emissions) emitted during the production of this alkali, which would help to reduce the carbon footprint associated with the production of alkali such as calcium and magnesium bearing materials used in chemical stabilization. The research focuses on understanding the optimum soil …

Enzymatic Removal Of Sulfonated Azo Dyes From Synthetic Textile Effluents Using Soybean Peroxidase, Temidayo Oyelere

Electronic Theses and Dissertations

The textile industry and other colour-oriented industries utilize azo dyes in extensive amounts. Dye effluents are recalcitrant to natural biodegradation, hence, causing toxic effects on the environment. Physiochemical treatment generates sludge which requires secondary disposal; advanced oxidation processes (AOPs) are cost and energy intensive; biological methods like anaerobic treatment via bacteria generate aromatic amines which are mutagenic and carcinogenic. A promising alternative that has shown great success in the treatment of wastewater is the enzymatic method. This thesis reports the enzymatic degradation of Reactive Black 5 (RB5), Acid Orange 7 (AO7), and Acid Orange 20 (AO20) from synthetic textile effluents …

Multiscale Evaluation Of The Effect Of Deicing Agents And Environmental Conditions On The Performance Of Asphalt Pavements In Cold Regions, Maryam Mihandoust

Electronic Theses and Dissertations

More than 70% of the United States' roadway network is located in regions subjected to severe winters, resulting in icy pavements that pose safety risks. Winter maintenance operations involving chloride-based deicers such as NaCl, CaCl2, and MgCl2 are essential for ensuring the safety, mobility, and functionality of roads. However, these deicers can lead to diminished pavement durability due to moisture-induced damage. This study examined the effects of these deicers on adhesion evolution and moisture-induced damage mechanisms of asphalt binder-aggregate systems at the macro-, centi-, micro-, and nanoscales. Macro-scale performance characteristics of PG 58-34 hot mix asphalt (HMA) specimens, including rutting, …

An Analysis Of The Effect Of Temperature On Asphalt Paving In South Dakota, S M Rahat Rashedi

Electronic Theses and Dissertations

Temperature is an important parameter to consider for asphalt paving since this work is generally susceptible to weather due to outdoor construction. The South Dakota Department of Transportation (SDDOT) developed working day weather charts in 1998 to address the expected adverse weather days. This thesis investigated the effect of temperature on adverse weather days for asphalt paving and compared them to the value reported in the 1998 SDDOT study. Moreover, the thesis also examined how closely the maximum temperature data from project sites' weekly progress reports (WPR) matched the data from the closest weather stations. When the maximum temperature (TMAX) …

Response Of Bed Shear Stress In Open-Channel Flow To A Sudden Change In Bed Roughness, Muhammad Farrukh Jamil

Electronic Theses and Dissertations

The estimation of bed shear stress plays a pivotal role in understanding the complexities of flow dynamics in both natural and engineered channels. The commonly employed log law formula offers a mechanism to compute the bed shear stress in open channel flows. However, its applicability in flow transition remains relatively unexplored. In this thesis, an in-depth investigation into the behavior of the velocity profiles and bed shear stress during the transition from Rough to Smooth (RTS) and Smooth to Rough (STR) beds is undertaken. Experiments were conducted on smooth-to-rough (STR) and rough-to-smooth (RTS) transitions in an open channel flume under …

Removal Of Disinfection Byproducts In Drinking Water Using Biological Filtration, Peng Dai

Electronic Theses and Dissertations

Drinking water disinfection is essential to protecting public health from waterborne diseases. However, the reaction of disinfectants with natural organic matter (NOM) can form carcinogenic disinfection byproducts (DBPs). Drinking water treatment facilities employ precursor control and alternative disinfectants to minimize regulated DBPs formation to comply with Environmental Protection Agency (EPA) guidelines. Despite their efficacy, some limitations have been observed during the application, such as increased cost of enhanced coagulation, high demand for sludge disposal, inconsistency in precursor removal, and formation of more toxic unregulated and unknown DBPs. Therefore, it is important to develop more efficient and safe strategies for DBPs …

Electrospun Recycled Polyethylene Terephthalate Microfibers As An Asphalt Mix Additive, Debbrata Datta

Electronic Theses and Dissertations

In recent decades, the use of different types of fibers in asphalt has become increasingly popular. Fibers are used in an asphalt mix to improve its durability and resistance against distresses such as rutting and cracking due to repetitive vehicle loading at high temperatures, and low-temperature contraction. Consequently, accurate rheological and performance characterization of asphalt binders and mixes containing fibers is of vital importance. With increased concerns over the environmental disruptions as a result of disposing end-of-life plastics in landfills and the need for improving sustainability of the construction materials, incorporating plastic in construction materials has always been an important …

Enzymatic Removal Of Diclofenac And Aceclofenac From Synthetic Wastewater By Soybean Peroxidase, Sarah Pishyar

Electronic Theses and Dissertations

Pharmaceutical medications that are a class of emerging contaminants have been detected in wastewater treatment facilities' influent and effluent, and they have reached water sources in amounts ranging from ng/L to ug/L. They threaten the environment and non-target life. Soybean peroxidase (SBP)-catalyzed process was studied to remove two non-steroidal anti-inflammatory drugs (NSAIDS) diclofenac and aceclofenac through enzymatic oxidation from synthetic wastewater. SBP can be extracted from soybean hulls, a by-product of the soybean industry. First, the experiments studied the viability of SBP-catalyzed removal on these two compounds, then the operational parameters including pH, the molar ratio between hydrogen peroxide and …

Circular Economy For Industrial, Commercial, And Institutional (Ici) Buildings: Comparison Of Alternative End-Of-The-Life Cycle Management Scenarios, Laleh Ghasemi

Electronic Theses and Dissertations

Environmental and economic impacts of the building sector have been a key source of concern for sustainable development. The circular economy concept is popular as a sustainable and innovative approach to resource management and waste reduction. Adopting circular economy principles in the construction sector could considerably optimize the materials use, reduce the carbon footprint, construction cost, and waste generation in this sector. The end-of-life phase of a building is a critical stage in its lifecycle that has a significant impact on the environment. However, the published literature has overlooked comparing the end-of-life management of building that facilitate the circularity of …

Enzymatic Removal Of Sulfa Drugs From Synthetic Wastewater By Soybean Peroxidase, Maryam Sharifzadeh

Electronic Theses and Dissertations

Sulfa drugs are a broad family of antibiotics that are widely used in the treatment of a wide range of infections, and they have been found in surface and groundwater, as well as present in sewage and effluent (treated sewage and sludge)municipal or industrial wastewater treatment plants (WWTPs). in concentrations of ng/L to >g/L. The continued presence of these so-called emerging pollutants (ECs) and their metabolites can cause adverse ecological effects, including bacterial resistance, even at very low concentrations. In this study, the first aim was to explore the feasibility of oxidation processes catalyzed by soybean peroxidase as an eco-friendly …

Nondestructive Evaluation Of Structural Defects In Concrete Slabs, Ehsanul Kabir

Electronic Theses and Dissertations

Nondestructive testing (NDT) is a reliable method for determining the structural integrity of new and old construction and understanding the condition of structural defects. It is widely acknowledged that the interpretation of nondestructive evaluation (NDE) has a significant impact on the reliability and consistency of this technology. However, NDT data acquisition remains subjective and heavily dependent on the operator’s knowledge and expertise. As a result, there are still issues to be resolved regarding the imaging and diagnostic procedures for NDT-based concrete inspection. NDT methods such as ground penetrating radar (GPR), and impact-echo (IE), have been extensively used to inspect concrete …

Implementation Of Ground Penetrating Radar (Gpr) And Complementary Non-Destructive Testing On Concrete Structures, Macy Spears

Electronic Theses and Dissertations

This study analyzes the application and practicality of different non-destructive testing (NDT) methods for the inspection of reinforced concrete. There are two studies discussed in this paper. The first one is a laboratory investigation, utilizing ground penetrating radar (GPR) on concrete slabs that consisted of simulated defects to mimic those found in real concrete structures. This served as a preliminary experiment to verify the GPR data with the design of the slabs. The following study describes a field investigation on an old bridge deck, which involved multiple testing methods. The techniques used were GPR, impact echo (IE), ultrasonic pulse echo …

Predictions Of The Dynamic Complex Modulus Of Non-Conventional Asphalt Concrete Using Machine Learning Techniques, Annie Benson

Electronic Theses and Dissertations

The complex dynamic modulus (|E*|) is a characterization property that defines the stiffness of an asphalt mixture. The dynamic modulus can be found through lab testing or predictions. Since lab testing can be time-consuming and expensive, the prediction method can be used as an alternative method. While a statistical method has been traditionally used for the |E*| prediction such as the Witczak’s predictive equations, machine learning (ML) is recently emerging as an alternative way that |E*| predictions can be made. This research attempted to predict the |E*| using several ML techniques including linear regression, support vector machines (SVM), decision trees, …

Accessing The Relative Sustainability Of Point-Of-Use Water Disinfection Technologies Through Costs And Environmental Impacts, Bright C. Elijah

Electronic Theses and Dissertations

According to the World Health Organization, 785 million people lack access to basic drinking water facilities, and 144 million people rely on surface water which is prone to microbial contamination. Point-of-use (POU) water disinfection technologies can be adopted to help address these issues by treating water at the household level; however, navigating various POU disinfection technologies for a given water source or location can be difficult. While numerous conventional POU technologies exist (e.g., boiling water, POU chlorination), new emerging POU technologies (e.g., using novel materials or advanced processes) have been coined by developers to be lower cost with higher treatment …

Modeling The Impact Of The Covid-19 Pandemic On Speeding At Rural Roadway Facilities In Maine Using Short-Term Speed And Traffic Count Data., Amirhossein Shahlaeegilan

Electronic Theses and Dissertations

The COVID-19 pandemic caused a significant change in traffic operations and safety. For instance, various U.S. states reported an increase in the rate of fatal and severe injury crashes over this duration. In April and May 2020, the comprehensive stay-at-home orders were issued across the country, including in Maine. These orders resulted in drastic reductions in traffic volume,switching working policies of noticeable number of corporations and educational administrations like universities to the remote working, closure of many organizations during the lockdown period, and people avoidance to public places to suppress the possible exposure to the virus were among the most …

Anthropogenic Effects On Tidal Distortion In A Tidal River, Matthew D. Fischer

Electronic Theses and Dissertations

Tidal rivers are landward portions of estuarine systems constituting the union between coastal, tidally controlled settings and rivers, where fluvial processes dominate. In these reaches, river discharge (mean flow) and tides are the two most important mechanisms in controlling geophysical flows. The processes governing water levels and current amplitudes in tidal rivers are highly nonlinear and modulated by external forcings- thus requiring sophisticated techniques for accurate prediction and forecasting. Physical oceanographers and estuarine physicists tend to limit their study area to the maximum extent of the horizontal tide (salinity intrusion), not the most landward point influenced by tidal water levels. …

Wave And Tide Driven Nearshore Processes: Implications For Tidal Asymmetry And Coastal Protection, Samuel Rickerich

Electronic Theses and Dissertations

The dynamics of the coastal ocean are driven by wind, buoyancy, tidal, and wave processes. In the context of the variability of the coastal ocean driven wave action, storm surge, and sea level rise, understanding interactions between physical processes and means to mitigate their effects is necessary. It is the goal of this study to extend the understanding of (i) wave and tidal hydrodynamics in coastal areas and (ii) explore adaptable coastal defense strategies for these environments. These goals are addressed through process-oriented hydrodynamic-wave simulations. As tides enter the coastal ocean, nonlinear interactions from bathymetry, friction, and variations in tidal …