Engineering Commons^™

Settling Performance In Wastewater Fed High Rate Algae Ponds, Elliott Blake Ripley

Master's Theses

Although high rate algae ponds (HRAPs) are a proven wastewater treatment technology with numerous environmental, social, and economic benefits, their widespread use has been hindered by inconsistent and unreliable settling performance. Hence, the goal of this thesis is to investigate how specific operational parameters affect the settling performance of HRAPs. Nine HRAPs (30 m² surface area, 0.3 m depth) were operated as three triplicate sets, with each set run on either a 2, 3, or 4 day HRT continuously from January 25, 2012 through April 11, 2013. Settling performance was determined (i) by measuring the TSS of Imhoff cone …

Reliability-Based Bridge Assessment Using Enhanced Monte Carlo To Simulate Extreme Traffic Loading, Bernard Enright, Donya Hajializadeh, Eugene J. Obrien

Conference papers

A framework is presented for the assessment of the safety of a bridge deck under actual traffic loading using an enhanced Monte Carlo method which attempts to reduce computational cost while preserving the advantages of more conventional, computationally intensive, simulation. To generate the bridge loading scenarios, an extensive Weigh-in-Motion (WIM) database is used to calibrate a sophisticated simulation model of two-directional traffic. Traffic and vehicle characteristics are generated from statistical distributions derived from measured traffic data. Two examples are used in this study to assess the usefulness and accuracy of the enhanced method. In the first, a simple example is …

An Innovative Protective Jacket For Structures Subject To Blast Loads: A Comprehensive Experimental And Simulation Study, Nicholas J. Carlson

Dissertations

As the importance of protective engineering and multi-hazard mitigation design has grown in recent years, the development of an effective structural protection system that aids in the preservation of life safety during blast events is an important topic of research in structural engineering. This protection is especially vital for blast and explosion mitigation, where a vehicle-borne bomb or an improvised explosive device can readily cause an under-designed structure with insufficient redundancy to undergo progressive collapse due to the removal of its first-floor columns. An especially pressing research need is the consideration of structures that require blast protection, but—due to time …

Urban Parking Economics And Land Consumption: A Case Study Of New Haven, Connecticut And Cambridge, Massachusetts, Bryan P. Blanc

Honors Scholar Theses

It has become increasingly apparent that providing copious off-street parking has deleterious effects on urban form and function. This study compares parking policy in New Haven, Connecticut and Cambridge, Massachusetts that have pursued very different types of parking policies that have resulted in different outcomes in terms of land use. Since 1951, off-street parking provision has increased by nearly 400% in New Haven, meanwhile both employment and residential population have declined in the city. In contrast, off-street parking provision in Cambridge has risen around 140% since 1952, while employment and residential populations in the city have increased by 50% and …

Partners On Campus: Open Access Transportation Research At Purdue University, David Scherer

Libraries Faculty and Staff Presentations

In the third community webinar presentation on regional and community partnerships, David Scherer, the Scholarly Repository Specialist at Purdue University, described how institutional repositories can support community engagement through the rewards of the partnership between Purdue's institutional repository, Purdue e-Pubs, and Indiana's Joint Transportation Research Program (JTRP). The Purdue Libraries and the Purdue University Press have worked to archive and showcase the fruits of over 75 years of strong collaboration between Purdue University and the Indiana Department of Transportation on research that has a significant impact on the safe and efficient operation of transportation systems throughout Indiana, the United States, …

Return To Traffic Of Full Depth Reclamation Pavements, Robert Benjamin Hill

Graduate Theses and Dissertations

Full-Depth Reclamation (FDR) is a cost-effective rehabilitation treatment for deteriorated pavements. However, when using asphalt emulsion based rehabilitation techniques one of the most challenging aspects of FDR is determining when traffic can be returned to the rehabilitated pavement surface. Since asphalt emulsion mixtures need ample time for curing, they cannot be sealed with a surface layer until the water has evaporated from the rehabilitated layer. It is often not possible to keep the road closed until all of the water has evaporated and the surface layer is placed, therefore, at some point the traffic needs to be returned to the …

Full Depth Reclamation: Bringing Developing Countries' Transportation Up To Speed, Sadie Smith

Civil Engineering Undergraduate Honors Theses

Often, a direct correlation is observed between a country’s transportation network and economic development. Evidence of this is observed all over the world. Full Depth Reclamation (FDR) is a roadway recycling technique that mills and mixes the existing roadway with a stabilizing agent and then re-compacts the mixture to create a thicker, stabilized pavement layer. This method is both cost effective and environmentally friendly, making it a very appealing option as the need to rehabilitate or increase the structural capacity of existing roads grows. In this study, the material characterization of FDR was examined as a composite material of both …

Noise-Insensitive Prognostic Evaluation Of Historic Masonry Structures, Ashley Haydock

All Theses

In recent years, a significant amount of research has been directed towards the development of prognostic methodologies to forecast the future health state of an engineering system assisting condition based maintenance. These prognostic methods, having furthered the maintenance practices for mechanical systems, have yet to be applied to historic masonry structures, many of which stand in an aged and degraded state. Implementation of prognostic methodologies to historic masonry structures can advance the planning of successful conservation and restoration efforts, ultimately prolonging the life of these heritage structures. This thesis presents a review of prognostic concepts and techniques available in the …

Stormwater Pollution Treatment Bmp Discharge Structures, Miles F. Simmons

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

Structural best management practices (BMPs) are used to capture and treat stormwater runoff. Most structural BMPs provide treatment by filtering runoff through a filter media or collecting it in a detention basin and slowly discharging it over an extended period of time to allow suspended solids and associated contaminants to settle out. The purpose of this study is to design an effective outlet structure that provides adequate filtration or slows discharge to 40 hours.

A model detention basin was constructed in the Civil Engineering Hydraulics Laboratory at the University of Nebraska-Lincoln (UNL) and two full scale outlet structures were tested …

Quantifying Annual Bridge Cost By Overweight Trucks In South Carolina, Linbo Chen

All Theses

With the economic development in recent decades, more trucks including overweight trucks are operating on the highways. As a result, many bridges are expected to carry more loads than they did in previous years. The impact of overweight trucks on existing bridges has been an urgent concern for the South Carolina Department of Transportation (SCDOT). There is a pressing need to quantify the annual bridge cost in South Carolina caused by trucks and, in particular, overweight trucks so that the SCDOT and the state legislators can determine the appropriate fee structure for operating overweight trucks. This research focused on quantifying …

Precast/Prestressed Concrete Truss-Girder For Roof Applications, Peter S. Samir

Department of Construction Engineering and Management: Dissertations, Theses, and Student Research

Steel trusses are the most popular system for supporting long span roofs in commercial buildings, such as warehouses and aircraft hangars. There are several advantages of steel trusses, such as lightweight, ease of handling and erection, and geometric flexibility. However, they have some drawbacks, such as high material and maintenance cost, and low fire resistance. In this paper, a precast concrete truss is proposed as an alternative to steel trusses for spans up to 160 ft. without intermediate supports. The proposed design is easy to produce and has lower construction and maintenance costs than steel trusses. The proposed design is …

Initial Elastic Modulus Degradation Using Pressuremeter And Standard Penetration Test Results At Two Sites, Dustin Robbins

UNLV Theses, Dissertations, Professional Papers, and Capstones

In-situ testing was performed at two sites consisting of pre-bored pressuremeter testing, seismic surface wave testing to develop a shear wave velocity profile, and Standard Penetration testing during the soil boring phase in order to evaluate the feasibility of using large shallow foundations for a project. This study focuses on a comparison of the in-situ direct measurements of soil stiffness obtained from this testing program. The small strain modulus obtained from the seismic surface wave test results is compared to the intermediate strain modulus obtained from both the initial loading pressuremeter modulus and reload pressuremeter modulus. The modulus calculated from …

Army Corps Of Engineers, U.S., Bert Chapman

Libraries Faculty and Staff Scholarship and Research

Provides an overview of how the U.S. Army Corps of Engineers has influenced historical and contemporary economic, environmental, and political developments in the American West.

Investigation Of Crashes And Identifying The Best Practices For Setting Up Speed Zones In Towns Along Rural Highways In Nevada, Krishna Prasad Shrestha

UNLV Theses, Dissertations, Professional Papers, and Capstones

In 2010, 51,664 crashes occurred in Nevada. Only about 9% of those crashes occurred in rural areas of the state. However, if only fatal crashes are considered, 41% of those fatal crashes occurred in rural areas. Generally, speed zones are provided in towns along rural highways to reduce speed-related crashes. However, a guideline is necessary for a consistent procedure to setup speed zones throughout the state. The main objectives of this study are to determine factors associated with crashes and to identify the best practices for setting up speed zones in towns along rural highways.

Eleven towns along rural highways …

Pavement Management Analysis Of Hamilton County Using Hdm-4 And Hpma, Trisha Sen

Masters Theses and Doctoral Dissertations

According to the 2009 ASCE Infrastructure Report Card, Tennessee roadways have received a B- due to lack of funding. This thesis focuses on the optimal utilization of available funds for Hamilton County using PMS. HDM-4 and HPMA are used to assess the existing pavement conditions and predict future conditions; estimate fuel consumption; calculate road agency costs and user costs; determine cost-effective maintenance treatment; and suggest optimum utilization of funds. From this study, fuel consumption is higher at peak hours due to reduced traffic speeds. User cost is higher on the state route than the interstate due to stop-and-go motion. Road …

Bs News May/June

Building Services Engineering

No abstract provided.

The Hydraulic Performance Of Perforated Pipe Under-Drains Surrounded By Loose Aggregate, Patrick Murphy

All Theses

Perforated pipes are commonly used in the construction industry for subsurface drains. These subsurface drains are installed to intercept and convey infiltrated runoff or groundwater. One common application of perforated pipe is to provide an under-drain for an infiltration trench or porous pavement best management practice (BMP). Perforated pipe is installed into a trench on a bed of aggregate ranging from 0 to 28 cm thick and, depending on the design objective, is laid flat or on a slope. However, the actual hydraulic performance of these pipes, i.e. the stage storage relationship, is poorly understood. The resulting flow is quite …

A Methodology For Designing Pervious Bicycle Lanes For Stormwater Management, Donald West Iii

All Theses

Bicycles have proven to be an efficient and reliable form of transportation in urban settings. Therefore, the addition of bicycle lanes into the transportation network could significantly impact and improve the sustainability of our infrastructure by reducing greenhouse emissions and improving the health of individuals who cycle on a regular basis. Pervious pavements are an approved (LID) strategy that could potentially be used to construct these new facilities thereby reducing the quantity of stormwater runoff and improving the water quality. Practicing engineers need both a design aid and research supported methods for designing these improvements before they can be fully …

Numerical Study Of The Structural Performance Of Large Panelized All-Wood Roof Diaphragms, Sami Pant

All Theses

The use of flexible roof diaphragms is very common in the United States, both for multi-family residential buildings and large-scale commercial buildings. Due to its simplicity, the traditional diaphragm design method is commonly used in diaphragm design, in particular for the design of diaphragms with relatively small dimensions. The traditional diaphragm design method assumes the axial forces developed in framing members under in-plane loading carried only by the perimeter chords. The traditional diaphragm design method has always been thought to be a conservative design method, especially when applied to large diaphragms. In recent years, the engineering community began to question …

College Level Residential Building Code Education: Current Status And Best Practice, Earl Shealy

All Theses

Community destruction and loss of life due to residential building code (RBC) violations still occur too frequently. Increasing RBC enforcement is often not possible due to lack of funds and resources. Teaching RBC to college-level construction students is another way to encourage greater code compliance and enhanced community resilience. This research assesses the current status of RBC education in accredited construction programs, identifies academic and industry perspectives of RBC education, and constructs 'best practice' RBC teaching strategies.
A mix method, exploratory approach including three distinct phases explains the current phenomenon - RBC education emphasis within university curriculums. My research found …

Vehicle-Infrastructure Integration Enabled Plug-In Hybrid Electric Vehicles For Energy Management, Yiming He

All Dissertations

The U.S. federal government is seeking useful applications of Vehicle-Infrastructure Integration (VII) to encourage a greener and more efficient transportation system; Plug-in Hybrid Electric Vehicles (PHEVs) are considered as one of the most promising automotive technologies for such an application. In this study, the author demonstrates a strategy to improve PHEV energy efficiency via the use of VII. This dissertation, which is composed of three published peer-reviewed journal articles, demonstrates the efficacies of the PHEV-VII system as regards to both the energy use and environmental impact under different scenarios.
The first article demonstrates the capabilities of and benefits achievable for …

Incorporating Natural Hazard Resistance Into The Life Cycle Assessment Framework, Jeffery Plumblee

All Dissertations

Hazard resistant building materials are not adequately represented by current LCA approaches, which do not account for environmental benefits of the avoided losses (e.g. avoided waste, avoided materials for repairs) promised by hazard resistant materials. The goal of this study was to encourage a more complete understanding of materials' environmental impacts by developing a framework to include hazard related damages in LCA.
Catastrophe modeling is a well-developed tool used by the insurance industry to assess the probability of hazard and quantify related impacts. These models were studied to identify required input data as well as the format of output results. …

Analysis Of Aggregate Distribution In Self-Consolidating Concrete, Brendan Ho

Civil Engineering Undergraduate Honors Theses

Concrete consists of several key ingredients: cement, water, and coarse and fine aggregate. Depending on the proportions of these ingredients, the strength and workability of a concrete mix can be affected adversely. Segregation is the separation of aggregate and cement paste, resulting in a lack of homogeneity. Self-consolidating concrete (SCC) does not require traditional consolidation; however, it can be affected by segregation. This project examines different SCC mixtures and establishes ranges of values for slump flow, T20 , Visual Stability Index (VSI), J-ring flow and J-ring flow spread that ensures proper aggregate distribution and therefore reduces the potential of segregation. …

Internal Curing Using Lightweight Fine Aggregate, Jonathan Kerby

Civil Engineering Undergraduate Honors Theses

Curing refers to the process of maintaining the hydration of the concrete as it hardens, or sets up. Concrete is cured to prevent things such as cracking and shrinkage. Autogenous shrinkage occurs internally in concrete because there isn’t enough water in the concrete for hydration, so the concrete rapidly draws out water to complete the hydration cycle, causing internal drying of concrete. There are two types of curing: external and internal. External curing utilizes water from external sources such as saturated burlap mats, ponding, or fogging. Internal curing supplies water from an internal source inside the concrete, such as saturated …

Ultrasonic Pulse Velocity Investigation Of Steel Fiber Reinforced Self-Compacted Concrete, Belayhun Tesfaye Gebretsadik

UNLV Theses, Dissertations, Professional Papers, and Capstones

Concrete is a basic material used for a number of applications in civil engineering projects. Structural concrete is brittle material under normal conditions. Therefore, by adding short and randomly distributed steel fibers, it is possible to improve the ductility and other basic properties of concrete. However, the addition of steel fibers results in loss of workability of the concrete, especially in self-compacted concrete. Therefore, in this study, ADVA-140 high range water reducer (HRWR) superplasticizer was added to improve the workability of self-compacted (SC), steel-fiber-reinforced concrete (SFRC). The amount of superplasticizer varied with the volume percentage of fiber for the beams; …

Air Vent Sizing In Low-Level Outlet Works For Small- To Medium-Sized Dams, Nathan W. Wright

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The majority of dams contain low-level outlet works, which typically consist of closed conduits that run through the dam, and are used to release water from the reservoir when the water level is below the level of the surface spillways. It is also used to flush the reservoir of sediments and to control the elevation of the reservoir. Low-level outlet works typically consist of a gate that controls the flow within a closed conduit that runs through the dam and an air vent that supplies air behind the gate. In the absence of properly designed air vents, negative pressures may …

Hazard Classification And Hydraulic Remediation Options For Flat-Topped And Ogee-Crested Low-Head Dams, Riley J. Olsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The dangerous hydraulic conditions that can form downstream of a low-head dam were investigated. These dangerous hydraulic conditions have been the cause of hundreds of drowning incidents since the construction of the first low-head dams. Two primary objectives were identified for this study, each of which were primarily performed using the Computational Fluid Dynamics software, Flow-3D^®, with physical models used to verify the numerical results. The first objective was the identification of a risk factor made up of easily measured parameters that could accurately predict when the dangerous hydraulic conditions are present at a low-head dam. The risk …

Applications Of Bayesian Statistics In Fluvial Bed Load Transport, Mark L. Schmelter

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The science of fluvial sediment transport studies the processes involved in the movement of river sediments. It is commonly understood that when rivers flood they have a great capacity to move sand, gravel, and even larger cobbles and boulders. This process is not only limited to the big floods that usually attract so much attention, but also the more common river flows play a very important role in forming a river. As engineers and scientists, we like to be able to develop equations and relationships that describe some natural phenomenon—in this case, fluvial sediment transport. While we are able to …

Platooning Safety And Capacity In Automated Electric Transportation, James Fishelson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Automated Electric Transportation (AET) proposes a system of automated platooning vehicles electrically powered by the roadway via wireless inductive power transfer. This has the potential to provide roadway transportation that is less congested, more flexible, cleaner, safer, and faster than the current system. The focus of this research is to show how platooning can be accomplished in a safe manner and what capacities such an automated platooning system can achieve. To accomplish this, first two collision models are developed to show the performance of automated platoons during an emergency braking scenario: a stochastic model coded in Matlab/Simulink and a deterministic …

Modeling Overlapping And Heterogeneous Perception Variance In Stochastic User Equilibrium Problem With Weibit Route Choice Model, Songyot Kitthamkesorn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Traffic assignment problem is an important component of the transportation planning model. State-of-the-practice traffic assignment models adopt the equilibrium principle to equilibrate the travel demand with the travel supply (e.g., highway and transit networks) under congestion. These models give the transportation network performance measures to compare among transportation alternatives for supporting the decision-making processes. The deterministic user equilibrium (DUE) principle is perhaps the most widely used in the traffic assignment problem. In this principle, all travelers are assumed to minimize their individual travel cost, such that only the lowest-cost route is used at equilibrium. However, this perfect knowledge assumption is …