Engineering Commons^™

A Microscopic Simulation Laboratory For Evaluation Of Off-Street Parking Systems, Yun Yuan

Theses and Dissertations

The parking industry produces an enormous amount of data every day that, properly analyzed, will change the way the industry operates. The collected data form patterns that, in most cases, would allow parking operators and property owners to better understand how to maximize revenue and decrease operating expenses and support the decisions such as how to set specific parking policies (e.g. electrical charging only parking space) to achieve the sustainable and eco-friendly parking.

However, there lacks an intelligent tool to assess the layout design and operational performance of parking lots to reduce the externalities and increase the revenue. To address …

Evaluation Of Bond Properties Between Fiber Reinforced Concrete Overlay And Substrate Concrete, Emad Okrush Alshammari

Theses and Dissertations

Bonded concrete overlay is the most economical and quick option in concrete rehabilitation methods to provide strength for the existing structure. Bonded concrete overlay strength rely on properties of both layers (substrate and new layers). Poor bonding in interface zone leads to two main failures of concrete overlays; debonding and cracks. There are several traditional factors affect bond strength such as water to cement (w/c) ratio, moisture condition, and surface roughness for substrate layer. However, the effect of using fiber consider a new variable affecting bond strength. Fiber reinforced concrete (FRC) is one type of overlay system which has been …

Evaluation And Influence Of Recycled Concrete Aggregate Base Layers On Hma Pavement Performance, Jessie Daniel Ramirez

Theses and Dissertations

This research investigated the influence of the RCA base layers on the HMA pavement performance as compared with CA base layers using laboratory tests on collected base layer materials and field tests on corresponding pavement sections. Field and laboratory testing programs were conducted to investigate RCA and CA base layer materials in which identified test sections at the selected pavement sites were subjected to testing using FWD, walking profiler, and DCP. Visual distress surveys were also conducted at the selected pavement sections. RCA and CA base layer samples were collected from these pavement sites and were subjected to a laboratory …

Big Data And Sensor Network For Construction Material Testing, Yao Shi

Theses and Dissertations

Engineers and contractors need to have a precise understanding of the development progress of concrete strength in the natural environment, which helps to save project time and cost. However, current practice of concrete construction depends on published data, charts and curves from laboratory tests. The data would not show frequently changing environmental conditions in the real world, which can affect concrete quality significantly. The objective of this research is to design a reliable and accurate method to validate test data of the strength developments of concrete specimens in early stages. The approach includes the following tasks: (1) arrange sensors to …

Numerical Modeling Of Submarine Minibasin Flow And Morphodynamics, Elena Bastianon

Theses and Dissertations

Intraslope basins, or minibasins, are important morphological features of the continental slope in both modern and ancient sedimentary systems. Minibasins have an elliptical or spherical shape with a steep inlet or proximal zone followed by an almost horizontal basin floor, and an overflow zone near the downstream basin lip. These basins are filled with sediment transported by successive events of turbidity currents and other types of submarine flows. The work presented here focuses on turbidity current sedimentation in intraslope minibasins, which is often described in terms of the ‘fill-and- spill’ conceptual model. The ‘fill-and-spill’ model has been used previously to …

The Restoration Of The Nile River And Its Delta, Egypt. Numerical Modeling, Basim Mohammed Naseef Al-Zaidi

Theses and Dissertations

The construction of the High Aswan Dam significantly reduced the flood flows and the sediment supply to the Egyptian portion of the Nile River. Consequences of this changes in river hydrology are diffuse channel bed erosion in the upstream part of the river, in- channel sedimentation in the downstream part of the system, delta recession, habitat deterioration, wetlands loss, water pollution, and environmental problems. The feasibility of a Nile River-Delta restoration project with controlled flow releases and sediment augmentations at Aswan is here investigated with the aid of site-specific one-dimensional morphodynamic models. The water source for the restoration project, based …

Characterization Of The Spatial And Temporal Changes In River Geometry And Sand Load With Field Data Analysis And 1d Numerical Modeling, Zeyad Ayoob Sulaiman

Theses and Dissertations

The quantification of the changes in channel geometry and sand load that have occurred on the Missouri River after engineering works and that characterize the Altamaha River in the fluvial-tidal transition zone is the main objective of this research. Dam construction and channelization on the Missouri River resulted in flow regulation, sediment shortage by dam reservoir trapping, channel straightening and narrowing. Quantifying the morphodynamic response of the Lower Missouri River to these engineering projects at short and long-time scales is a difficult problem that we approach with the analysis of the available field data and with the aid of a …

Hydrophobic Self-Cleaning Coatings For Sustainable Infrastructure, Evgeniya Alexandrova

Theses and Dissertations

Durable two-layer hydrophobic coatings with photocatalytic properties demonstrated a good decomposition of NOx up to 23 %. The first layer of the coating is based on the application of durable titanium phosphate structures. The hydrophobic properties of the coating with a water contact angle of 114° were achieved by the application of water-based siloxane emulsion on the surface of the first layer. Conducted research has demonstrated that the use of hydrophobic coating in comparison with reference TiO2-phosphate can slightly reduce the efficiency for the decomposition of NOx by 8 %; however, this feature can be considered as an acceptable trade-off …

Biogas Quality Improvement Using Water Wash And Phosphorus Recovery As Struvite In Jones Island Wwtp, Md Abul Bashar

Theses and Dissertations

Raw biogas from anaerobic digestion has a methane content of 50 to 60% and a carbon dioxide content of 40 to 50% on a molar basis (Bortoluzzi, Gatti, Sogni, & Consonni, 2014). Milwaukee Metropolitan Sewerage District (MMSD)’s Jones Island Waste Water Treatment Plant (WWTP) uses the biogas supplied from South Shore WWTP in drying Milorganite, a slow-release phosphate fertilizer. But with only 45% methane, the gas cannot be used for sophisticated purposes. To maximize its potential as energy source, the methane content must be upgraded to its market competitor natural gas. Based on simulation results from Aspen Plus software - …

Advanced Quantitative Methods For Imminent Detection Of Crash Prone Conditions And Safety Evaluation, Zhi Chen

Theses and Dissertations

Crashes can be accurately predicted through reliable data sources and rigorous statistical models; and prevented through data-driven, evidence-based traffic control strategies. Both predictive analysis and analysis to estimate the causal effect of traffic variables of real-time crashes are instrumental to crash prediction and a better understanding of the mechanism of crash occurrence. However, the research on the second analysis type is very limited for real-time crash prediction; and the conventional predictive analysis using inductive loop detector data has accuracy issues related to inconsistently and distantly spaced loop detectors. The effectiveness of traffic control strategies for improving safety performance cannot be …

Lead Corrosion Inhibitors In Drinking Water, Seyedsoheil Hosseinibalajadeh

Theses and Dissertations

Lead-containing materials that include lead pipes, fittings, solder, and fixtures are widely present in drinking water distribution systems in North America and Europe. Their internal corrosion provides the most significant source of lead in drinking water. Several mechanisms contribute to the corrosion of lead-containing materials, including material heterogeneity, galvanic interaction, and reaction with progressively water constituents and to protect consumers from lead exposure, the Lead and Copper Rule (LCR) set the lead action level to 15 μg/L for a 1-L first-draw sample of tap water. Today more than half of the water treatment utilities in the U.S. are using phosphates …

Development Of A Small Diameter Rapid Pressuremeter Test For Unbound Pavement Layer Evaluations, Thaddeus Joseph Misilo Iii

Theses and Dissertations

Six inch and 12 inch long small diameter pressuremeter (SDPMT) probes were developed and tested extensively to determine in situ stress-strain properties of unbound pavement layers. They were deployed in the same hole as the one made during nuclear density testing. The stress strain response of conventional or incremental and continuous or rapid strain controlled tests in unbound pavement layers were evaluated at four sites in Brevard County, Florida. One test site was A-1-b base material, one was A-3 subgrade and two were compacted A-3 fill of subgrade quality. The SDPMT results were compared with nuclear density dry and wet …

Tornado And Hurricane Hazards: Reconnaissance, Structural Analysis And Vulnerability Modeling, Fernando Simon Plaz

Theses and Dissertations

This thesis is composed of three main projects which are directly linked to wind engineering. Hazards such as tornadoes and hurricanes are natural disasters which causes human and economic losses. First, the study consists on a forensic analysis made to a Tornado that hit Funing and Sheyang counties, in the Jiangsu Province of China. 21 villages, mostly rural, experienced important damages to different type of structures. The work will describe field observations and structural analyses made to communication towers. Preliminary estimates of wind speeds will be given based on the observations and the analysis as well as recommendations to reduce …

Seismic Tensile Force On Steel Girder-Concrete Wall Connections In High-Rise Composite Building Structures, Yuchen Hui

Theses and Dissertations

Composite steel frame – reinforced concrete (RC) core wall structures are often used in high-rise buildings. It is commonly assumed that reinforced concrete walls carry lateral loads such as earthquake loads, while steel frames carry gravity loads. As a result, lateral loads are directly applied to wall elements during a typical structural analysis. This design based on this simplification can be adequate for most structural members except the connections between steel girders and RC walls. This study focuses on the tensile loads on girder-wall connections for composite building structures in earthquakes.

Computer models were created for a 28-story composite structures …

Data-Driven Optimization Models For Feeder Bus Network Design, Yaojun Wang

Theses and Dissertations

Urbanization is not a modern phenomenon. However, it is worthwhile to note that the world urban population growth curve has up till recently followed a quadratic-hyperbolic pattern (Korotayey and Khaltourina, 2006). As cities become larger and their population expand, large and growing metropolises have to face the enormous traffic demand. To alleviate the increasing traffic congestion, public transit has been considered as the ideal solution to such troubles and problems restricting urban development. The metro is a type of efficient, dependable and high-capacity public transport adapted in metropolises worldwide. At the same time, the residents from crowded cities migrated to …

Comprehensive Comparison Of Steel Framed Fabric And Conventionally Constructed Aircraft Hangars, Justin M. Iungerich

Theses and Dissertations

Through the life of the United States Air Force (USAF), the accepted method for constructing permanent aircraft hangars is the use of materials such as steel and concrete. However, the emerging type of construction known as steel framed fabric (SFF) construction shows potential to meet the requirements of the USAF at a lower life-cycle cost and with faster construction delivery. A comprehensive comparison to conventional hangars is conducted through the means of an extensive literature review, case study analysis, structural analysis with the use of finite element analysis (FEA) software, and a life-cycle cost comparison. Through examination of Department of …

Defining Success In Air Force Infrastructure Asset Management Through Use Of The Delphi Method, Brendan J. Maestas

Theses and Dissertations

Asset Management has a history of policy mandates within the US Government dating back to 1990’s. In order to accomplish these many directives, the Air Force Civil Engineer community has adopted a mindset and framework commonly referred to as Asset Management. Despite numerous references and guidance to establish Asset Management principles, the Air Force has not yet developed a clear and concise way to define or measure overarching success in Asset Management. This research effort focuses on closing the knowledge gap between issued policy and implementation. It examines Asset Management implementation efforts in other government agencies, private industries, and in …

Occupational Noise Dose Reduction Via Behavior Modification Using In-Ear Dosimetry Among Usaf Personnel Exposed To Continuous Impulse Noise, Jesse A. Trawick

Theses and Dissertations

The purpose of this research was to investigate the use of in-ear noise dosimetry and worker feedback to reduce noise exposures among combat arms instructors and heavy equipment operators in the Air Force. Specifically, this thesis sought to determine how effectively hearing protection devices (HPDs) are being utilized currently, and whether providing at-ear noise exposure data to workers results in reduced noise exposures or changes in worker attitude. These questions were addressed by performing a six-month field study using dosimeters to record worker noise exposures under HPDs. Subjects served as their own control, receiving feedback in only the latter half …

Analysis Of Cross-Cultural Training Provided To United States Air Force Civil Engineer Officers, And How Engineering Efforts Are Affected On Overseas Air Force Installations: A Delphi Study, Bianca E. Boney

Theses and Dissertations

U.S. military personnel perform a wide array of roles and missions at locations all over the world. As such, this research investigates and describes the current process of cultural training, its adequacy, and examines how cultural differences and collaboration efforts may impede or enhance project management and engineering efforts. This qualitative analysis is conducted through a Delphi study of U.S. Air Force officers consisting of 15 subject matter experts (SMEs) with experiences from 13 different countries. All reported to have daily to weekly interactions with locals and foreign partners due to job requirements; however, no set standard of cultural training …

Development Of Models And Solution Methods For Different Drayage Applications, Samaneh Shiri

Theses and Dissertations

In the last decades, intermodal freight transport is becoming more attractive in the global supply chains and freight transport policy makings. Intermodal freight transport provides a cost-effective, reliable, and efficient movement of freight by utilizing the strengths of different transport modes. The initial and final segment of intermodal freight transport, performed by truck, is known as “drayage.” The scheduling of truck movements in drayage operation within the service area of an intermodal terminal is an operational problem which leads to a truck scheduling problem that determines the efficient schedule of trucks while satisfying all transportation demands and constraints. Drayage accounts …

Meso-Scale Simulation Of Size-Dependent Shear Behavior In Glass Fiber Reinforced Polymer Reinforced Concrete Beams Without Stirrups, Sina Khodaie

Theses and Dissertations

There is extensive experimental evidence of the decrease in the shear stress at failure at increasing effective depths in concrete beams reinforced with glass fiberreinforced polymer (GFRP) bars without shear reinforcement. An important practical implication is that extrapolating strength values from typical laboratory-scaled experiments to design larger members may be misleading. The complexity of the underlying mechanics is reflected in the difficulty of using commercially available numerical tools to accurately estimate shear strength irrespective of beam size. This dissertation presents research on a Lattice Discrete Particle Model (LDPM) based model to simulate the response of scaled slender GFRP reinforced concrete …

Hydrothermal Carbonization Of Food Waste For Nutrient Recovery And Reuse, Ifeolu M. Idowu

Theses and Dissertations

Food waste represents a rather large and currently underutilized source of potentially available and reusable nutrients. Laboratory-scale experiments evaluating the hydrothermal carbonization of food wastes collected from restaurants were conducted to understand how changes in feedstock composition and carbonization process conditions influence primary and secondary nutrient fate. Results from this work indicate that at all evaluated reaction times and temperatures, the majority of nitrogen, calcium, and magnesium remain integrated within the solid-phase, while the majority of potassium and sodium reside in the liquid-phase. The fate of phosphorus is dependent on reaction times and temperatures, with solid-phase integration increasing with higher …

Computations Of The Dynamic Fracture Of Plane Structures By The Extended Finite Element Method, Iman Asareh

Theses and Dissertations

Finite element methods for the simulation of dynamic fracture in plane structures are presented. The method is a modified extended finite element method (XFEM) for dynamic fracture simulations with a new methodology to construct the XFEM basis functions for discontinuities. In contrast to conventional XFEM in which the extended interpolation is defined to only capture the discontinuities, the proposed method describes the enrichment functions so that they reproduce both the discontinuities and the polynomial bases of sufficiently high order which are critical for finite element convergence. Such enrichment functions, by adopting the Duffy’s transformation, can be simply defined in terms …

Assessing Exposure To Occupants In An Indoor Space Due To Expirated Aerosols: Application Of Computational Fluid Dynamics, Firoza Binte Omar

Theses and Dissertations

Indoor environment is an important issue for the well-being of the society. In the United States more than 90% people spend their time indoor, indoor air pollution is more culpable than the pollution outside air. Two third of US businesses lose more than $100,000 per year due to workplace related illness. The trend of sharing the work space has an impact on total sick leaves in a company. Infectious particles released by a flu sufferer’s sneezing, coughing or even laughing can be a vital source. A thorough analysis on infectious particles’ transmission and air flow of the space can provide …

Acoustic Emission Detection In 304h Stainless Steel Due To Intergranular Stress Corrosion Cracking, Joseph W. Hill

Theses and Dissertations

Storage of spent nuclear fuel has become problematic in past decades due to delayed completion of long-term repositories for various reasons. Temporary storage containers called Dry Cask Storage Systems (DCSS) made of stainless-steel and surrounded by reinforced concrete have been in use but are exceeding their designed usage periods. Defects in canisters can be exacerbated in climates susceptible to high humidity and salinity levels. As inspection and relicensing of DCSS increases, more efficient monitoring techniques could save nuclear facilities valuable time and resources. Crack detection of the canister walls or welds in real time may be possible utilizing acoustic emission …

Understanding Geopolymerization Process For Enhancement Of Mechanical Properties Of Fly Ash Based-Geopolymer Concrete, Lateef Najeh Assi

Theses and Dissertations

Concrete is a major construction material that is largely made up of cement. Unfortunately, the manufacturing process for the cement currently used to produce concrete releases a great deal of CO2, which endangers the environment. Hence, finding alternatives to ordinary Portland cement is of extreme importance. The intellectual contribution of this dissertation is the development of an improved understanding of the geopolymerization process so that the compressive strength of cement can be maximized while the need for external heating is minimized. The intent is to create a substance to replace commonly used cement without sacrificing other beneficial properties. The first …

Evaluation Of Sonocatalytic Degradation Of Ibuprofen And Sulfamethoxazole In The Presence Of Various Catalysts, Yasir Alhamadani

Theses and Dissertations

Over the last two decades, large quantities of products, such as medicines, disinfectants, and personal care products, have been released into surface waters and wastewater treatment facilities by the pharmaceutical and chemical industries which have come to the attention of scientists with regard to their impacts on life in lakes, rivers, and groundwater. Among various types of treatment processes, ultrasonic (US) treatment process was used in this study to investigate the effect catalysts and removal of selected pharmaceutical’s (PhACs) compounds (ibuprofen (IBP) and sulfamethoxazole (SMX)). Carbon nanomaterials (CNMs) have become candidates for numerous applications in nanocomposites, microelectric devices, sensors, energy …

Nondestructive Evaluation Of Corrosion Damage In Reinforced Concrete Aged Slab Specimen, Rawya Abdulsattar Abduljabbar

Theses and Dissertations

The deterioration of concrete bridge decks presents a maintenance challenge for most transportation agencies and bridge owners. This problem increases during the freeze-thaw cycle. De-icing salts can accelerate the deterioration process. Corrosion of steel reinforcement in reinforced concrete structures is considered a dominant factor causing premature deterioration, especially those structures located in a coastal environment. The resulting corrosion product produced has several times the volume of steel, resulting in cracking of the concrete cover if the corrosion is significant. In this study, a bridge deck specimen was subjected to an artificial environment to accelerate the corrosion process. Prior to this …

Impact Of Critical Path Method (Cpm) Of Scheduling On On-Time Completion Of Transportation Projects, Fahim Ahmed

Theses and Dissertations

This study addresses the effectiveness of Critical Path Method (CPM) scheduling on project delivery. Specifically, the on-time completion of projects with and without a CPM schedule is explored. The paper uses data from 2,097 South Carolina transportation projects let after February 2008 and substantially completed by August 2015. The delay analysis uses the original contract completion date as well as the completion date adjusted by change orders. Chi-Squared tests are used to examine the relationship between CPM scheduled projects and delayed projects, and t-tests are used to compare the mean delay (in days) between CPM scheduled and unscheduled projects. The …

Probabilistic Multilevel Constitutive Model Of The Compressive Strength Of Hardened Cement Paste Reinforced With Mwcnts, Yohanna Mejia Cruz

Theses and Dissertations

Constitutive models available in the literature typically describe the compressive strength of ordinary Portland cement paste (OPC) in a deterministic fashion, in some cases as a function of variables such as W/C, porosity, and the clinker chemical composition. The significant effect of the proportion of W/C on the final strength, porosity and density have been reported in several works in material science. Some studies have shown that the addition of MWCNTs can also modify the microstructure of cement significantly, and improve compressive strength and other mechanical and physical properties. In principle, W/C, MWCNTs addition, porosity, density, and compressive strength are …