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Full-Text Articles in Engineering

Wave Reflection Characteristics Of Permeable And Impermeable Submerged Trapezoidal Breakwaters, Mathew Hornack May 2011

Wave Reflection Characteristics Of Permeable And Impermeable Submerged Trapezoidal Breakwaters, Mathew Hornack

All Theses

The present study aims to quantify reflection coefficients in the vicinity of impermeable and permeable submerged trapezoidal breakwaters. Three impermeable breakwater models are tested, each with a unique side slope for the breakwater faces. Two permeable models are tested, one made of PVC pipe and the other consisting of golf balls contained within a mesh cage, to provide two separate porosities. Testing is carried out at the Clemson University Flow Physics Laboratory in a laboratory wave tank with the inclusion of a 1:20 sloping sandy beach to simulate natural environmental conditions. Wave elevations are collected during experiments by two capacitance …


Fiber Reinforced Polymer Bridge Decks, Rita E. Rodriguez-Vera, Nicolas J. Lombardi, Marcelo A.S. Machado, Judy Liu, Elisa D. Sotelino May 2011

Fiber Reinforced Polymer Bridge Decks, Rita E. Rodriguez-Vera, Nicolas J. Lombardi, Marcelo A.S. Machado, Judy Liu, Elisa D. Sotelino

JTRP Technical Reports

The overarching goal of this study was to perform a comprehensive evaluation of various issues related to the strength and serviceability of the FRP deck panels that are available in the industry. Specific objectives were to establish critical limit states to be considered in the design of FRP deck panel, to provide performance specifications to designers, and to develop evaluation techniques for the deck panels in service.

Two different FRP panels were studied during the research project: a sandwich panel and a pultruded panel. The sandwich panel was initially selected for the rehabilitation case study bridge. However, for a variety …


Assessing The Potential For Seepage Barrier Defects To Propagate Into Seepage Erosion Mechanisms, Ryan G. Van Leuven May 2011

Assessing The Potential For Seepage Barrier Defects To Propagate Into Seepage Erosion Mechanisms, Ryan G. Van Leuven

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Seepage barriers have been used extensively to mitigate seepage problems in dams and levees. Although the design of many of these dams and levees has been based on intact barriers, seepage barriers have been shown to be susceptible to deformation and cracking when high differential hydraulic pressures act across the barrier. Under certain conditions, these cracks can lead to serious seepage problems, which could potentially lead to the development of a low-resistance seepage pathway. Three scenarios have been identified where there is the potential for erosion to occur adjacent to a crack in a barrier: 1) erosion at the interface …


Discharge Coefficient Performance Of Venturi, Standard Concentric Orifice Plate, V-Cone, And Wedge Flow Meters At Small Reynolds Numbers, Colter L. Hollingshead May 2011

Discharge Coefficient Performance Of Venturi, Standard Concentric Orifice Plate, V-Cone, And Wedge Flow Meters At Small Reynolds Numbers, Colter L. Hollingshead

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The relationship between the Reynolds number (Re) and discharge coefficients (C) was investigated through differential pressure flow meters. The focus of the study was directed toward very small Reynolds numbers commonly associated with pipeline transportation of viscous fluids. There is currently a relatively small amount of research that has been performed in this area for the Venturi, standard orifice plate, V-cone, and wedge flow meters. The Computational Fluid Dynamics (CFD) program FLUENT© was used to perform the research, while GAMBIT© was used as the preprocessing tool for the flow meter models created. Heavy oil and water were used …


Live Load Test And Finite Element Model Analysis Of A Box Girder Bridge For The Long Term Bridge Performance Program, Dereck J. Hodson May 2011

Live Load Test And Finite Element Model Analysis Of A Box Girder Bridge For The Long Term Bridge Performance Program, Dereck J. Hodson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Long Term Bridge Performance (LTBP) Program is a 20-year program initiated by the Federal Highway Administration to better understand the behavior of highway bridges as they deteriorate due to environmental variables and vehicle loads. Part of this program includes the periodic testing of selected bridges.

The Lambert Road Bridge was subjected to nondestructive testing in the fall of 2009. Part of this testing included a live load test. This test involved driving two heavy trucks across the instrumented bridge on selected load paths. The bridge was instrumented with strain, displacement, and tilt sensors. This collected data was used to …


Evaluation And Improvements On Row-Column Order Bias And Grid Orientation Bias Of The Progressive Morphological Filter Of Lidar Data, Kody Potter May 2011

Evaluation And Improvements On Row-Column Order Bias And Grid Orientation Bias Of The Progressive Morphological Filter Of Lidar Data, Kody Potter

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis reviews algorithms that have been developed for classifying lidar data and identifies a progressive morphological filter for evaluation and improvement. Two potential weaknesses evaluated include the row-column order bias and grid orientation bias.

Four different row-column orderings were developed to test for bias associated with the order choice. Moreover, a method rotating the filter grid to a series of angles was developed for testing bias associated with grid orientation. Measures of success of the improvements include Type I and II errors, where results are compared with a hand-produced "truth" dataset. Two datasets, one urban, the other rural, were …


Live-Load Testing And Finite-Element Analysis Of A Steel Cantilevered Deck Arched Pratt Truss Bridge For The Long-Term Bridge Performance Program, Matthew P. Laurendeau May 2011

Live-Load Testing And Finite-Element Analysis Of A Steel Cantilevered Deck Arched Pratt Truss Bridge For The Long-Term Bridge Performance Program, Matthew P. Laurendeau

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Long Term Bridge Performance (LTBP) program is an organization within the Federal Highway Administration that inspects, tests, analyzes, and observes, for an extended period of time, a variety of bridge types throughout the United States. Part of the program includes periodic testing of select bridges of a span of 20 years. The Kettle River Bridge located outside of Sandstone, Minnesota was selected for study due to its unique design.

The Kettle River Bridge is a historical steel cantilevered deck arched Pratt truss bridge. The bridge was instrumented with 151 strain gauges on various floor and truss members along with …


Estimation Of Field Alfalfa Evapotranspiration In A Windy, Arid Environment, J. Burdette Barker May 2011

Estimation Of Field Alfalfa Evapotranspiration In A Windy, Arid Environment, J. Burdette Barker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Evapotranspiration (ET) of center pivot irrigated alfalfa was studied in the windy, arid, Curlew Valley, Northern Box Elder County, Utah, during the summers of 2009 and 2010. ET was estimated using eddy covariance (EC) and surface renewal (SR) techniques. ET estimates from the EC and SR analyses were compared with estimates using ASCE Standardized Reference ET Equation, with both dual and mean crop coefficients.

EC energy balance closure was 0.80, on average, in 2009 and 0.76 in 2010. The SR weighting parameter (α) was calculated through linear regression of EC and SR sensible heat flux estimates. Alpha was found to …


Performance Of Transverse Post-Tensioned Joints Subjected To Negative Bending And Shear Stresses On Full Scale, Full Depth, Precast Concrete Bridge Deck System, Kayde Steven Roberts May 2011

Performance Of Transverse Post-Tensioned Joints Subjected To Negative Bending And Shear Stresses On Full Scale, Full Depth, Precast Concrete Bridge Deck System, Kayde Steven Roberts

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Accelerated bridge construction has quickly become the preferred method for the Utah Department of Transportation (UDOT) as well as many other DOT’s across the United States. This type of construction requires the use of full depth precast panels for the construction of the bridge deck. The segmented deck panels produce transverse joints between panels and have come to be known as the weakest portion of the deck. Cracking often occurs at these joints and is reflected through the deck overlay where water accesses and begins corrosion of the reinforcement and superstructure below. For this reason post-tensioning of the deck panels …


Complex Vs Profiles To 100 M Depth From Rayleigh Waves And 3-D Vs Model For Las Vegas Valley, Helena Murvosh May 2011

Complex Vs Profiles To 100 M Depth From Rayleigh Waves And 3-D Vs Model For Las Vegas Valley, Helena Murvosh

UNLV Theses, Dissertations, Professional Papers, and Capstones

A three-dimensional (3-D) shear wave velocity (VS) model was developed for the heterogeneous shallow sediments (to nearly 400 m) of the Las Vegas Valley (LVV), Nevada. The model was based on more than 200 VS profiles and 1400 geologic well logs. Five sediment units including a cemented unit were defined from geologic log descriptions. A characteristic VS profile for four of the units was obtained by correlating between closely spaced pairs of VS and sediment data; a constant VS was assigned to the cemented unit. VS profiles were then assigned to each well location based on type of sediment according …


Impacts Of Climate Change And Weather Modification On Hydrologic Characteristics Of Watersheds In The Western United States, Anil Acharya May 2011

Impacts Of Climate Change And Weather Modification On Hydrologic Characteristics Of Watersheds In The Western United States, Anil Acharya

UNLV Theses, Dissertations, Professional Papers, and Capstones

This research quantifies the impacts of climate change and weather modification (WM) on hydrologic characteristics of watersheds in the arid regions of the western United States. This research performs a long-term simulation of streamflow for present and future climate conditions in the North Platte (NP) Watershed, Wyoming; a shorter duration simulation is then performed to observe the likely impacts of event based changes in an urban watershed in Las Vegas, Nevada.

First, a study is carried out in Chapter 3 that evaluates the impacts of WM on water supply by developing a hydrologic model for the NP Watershed. The variable …


Association Of Oceanic-Atmospheric Oscillations And Hydroclimatic Variables In The Colorado River Basin, Ajay Kalra May 2011

Association Of Oceanic-Atmospheric Oscillations And Hydroclimatic Variables In The Colorado River Basin, Ajay Kalra

UNLV Theses, Dissertations, Professional Papers, and Capstones

With increasing evidence of climatic variability, there is a need to improve forecast for hydroclimatic variables i.e., precipitation and streamflow preserving their spatial and temporal variability. Climatologists have identified different oceanic-atmospheric oscillations that seem to influence the behavior of these variables and in turn can be used to extend the forecast lead time. In the absence of a good physical understanding of the linkages between oceanic-atmospheric oscillations and hydrological processes, it is difficult to construct a physical model. An attractive alternative to physically based models are the Artificial Intelligence (AI) type models, also referred to as machine learning or data-driven …


A Finite Element Model For Coupled Deformation-Flow Analysis Of Unsaturated Soil-Structure Systems And Its Validation, Hadakopan Krishnapillai May 2011

A Finite Element Model For Coupled Deformation-Flow Analysis Of Unsaturated Soil-Structure Systems And Its Validation, Hadakopan Krishnapillai

All Dissertations

The unsaturated soil mechanics is one of the emerging fields that require extensive studies to understand its behavior under various loading and environmental conditions. Unsaturated soil consists of three bulk phases: solid, liquid and gas and three interfaces: solid-liquid, liquid-gas and gas-solid. It is generally accepted that the interaction among various bulk phases and interfaces has to be taken into account in the characterization of unsaturated soils. The behavior of soil-structure systems is complex and the complexity further increases when the structure is located in unsaturated soil. Numerical methods such as the finite element method are ideally suited for elucidating …


An Asset Management Framework For Addressing The New Mutcd Traffic Sign Retroreflectivity Standards, Eric Hulme, Sarah Ml Hubbard, Grant D. Farnsworth, Alexander M. Hainen, Steve M. Remias, Darcy M. Bullock May 2011

An Asset Management Framework For Addressing The New Mutcd Traffic Sign Retroreflectivity Standards, Eric Hulme, Sarah Ml Hubbard, Grant D. Farnsworth, Alexander M. Hainen, Steve M. Remias, Darcy M. Bullock

Indiana Local Technical Assistance Program (LTAP) Technical Reports

The 2009 Manual on Uniform Traffic Control Devices (MUTCD) requires that all agencies implement traffic sign management programs by January 8th, 2012. Most agencies are expected to adopt some type of systematic replacement policy based on life expectancy, augmented by visual inspection to identify signs with obvious damage. Several previous efforts have developed models based on average degradation of the retroreflective sheeting as the signs age. This paper develops a series of survival curves characterizing the percent of signs that pass the retroreflectivity standards for signs ranging from 0 to 20 years. The curves representing expected conformance with the retroreflectivity …


How Do Millennial Engineering And Technology Students Experience Learning Through Traditional Teaching Methods Employed In The University Setting?, Elizabeth A. Howard May 2011

How Do Millennial Engineering And Technology Students Experience Learning Through Traditional Teaching Methods Employed In The University Setting?, Elizabeth A. Howard

Department of Computer Graphics Technology Degree Theses

The purpose of the study was to document and analyze how Millennial engineering and technology students experience learning in large lecture classrooms. To help achieve this purpose, perceptions Millennials have toward traditional teaching methods employed in large lecture classes were analyzed and discussed. Additionally, this study documented how Millennials experienced technology within large lecture classrooms. A learning model depicting how Millennials experience learning within the large lecture classroom was created based on the results of this study. This model employed three separate tools utilized within the large lecture classroom. These tools: Lecture, Technology, and Homework, work together to synthesize learning …


Bs News May/June May 2011

Bs News May/June

Building Services Engineering

No abstract provided.


Effect Of Selected Parameters On Aggregate Reactivity In Accelerated Mortar Bar Test Method: Aggregate Size & Deicers, Sujay Math May 2011

Effect Of Selected Parameters On Aggregate Reactivity In Accelerated Mortar Bar Test Method: Aggregate Size & Deicers, Sujay Math

All Theses

Abstract
Alkali Silica Reaction (ASR) is a chemical reaction between reactive siliceous aggregates and the alkali hydroxides present in the pore solution of hydrated cement paste in concrete. The chemical reaction produces ASR gel that is hygroscopic in nature and is volumetrically unstable in the presence of moisture. Expansion resulting from the swelling of the gel creates tensile stresses in the concrete leading to cracking and distress.
While ASR distress has been known to occur in concrete for over last 70 years, there has been an increase in the frequency of this distress in recent years. This is primarily due …


Piano Key Weir Head Discharge Relationships, Ricky M. Anderson May 2011

Piano Key Weir Head Discharge Relationships, Ricky M. Anderson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A piano key (PK) weir is a type of nonlinear (labyrinth-type) weir developed specifically for free-surface flow control structures with relatively small spillway footprints. Currently, no generally accepted standard PK weir design procedure is available. This is due, in part, to the large number of geometric parameters and a limited understanding of their effects on discharge efficiency (discharge efficiency is quantified by the discharge coefficient of the standard weir equation). However, Hydrocoop, a non-profit French dam spillways association, has recommended a PK weir design and a head-discharge relationship specific to that geometry.

To develop a better understanding of the effects …


Dynamic Testing For A Steel Truss Bridge For The Long Term Bridge Performance Program, Cody Joshua Santos May 2011

Dynamic Testing For A Steel Truss Bridge For The Long Term Bridge Performance Program, Cody Joshua Santos

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Under the direction of the Federal Highway Administration the Long Term Bridge Performance Program (LTBP) selected Minnesota Bridge number 5718 as a pilot bridge for evaluation. This program focuses on the monitoring of bridges for a 20-year period to understand the structural behavior over time due to the various loads and weathering. In monitoring this bridge a better understanding can be acquired for the maintenance issues related to the nation's deteriorating bridge infrastructure.

Bridge Number 5718, which is located just outside of Sandstone Minnesota, is a steel truss bridge that spans the Kettle River. Constant monitoring of the bridge along …


Two Dimensional Modeling Of Wind Effects On A Bridge Section Using Finite Difference Method, Jessica Carreiro May 2011

Two Dimensional Modeling Of Wind Effects On A Bridge Section Using Finite Difference Method, Jessica Carreiro

Civil Engineering Undergraduate Honors Theses

Wind effects on long span bridges are a major concern for bridge design. Wind acts as a dynamic load on the bridge deck causing the bridge to react in ways not accounted for in static load design. Attention to these effects increased tremendously after famous bridge collapses, such as the Tacoma Narrows Bridge in 1940. Due to this collapse and others, engineers were made painfully aware that wind phenomena, such as flutter and vortex shedding, can cause major structural damage if not considered in the design process. The solution for many years since has been to conduct wind tunnel tests …


Effects Of Piston Uplift, Piston Friction, And Machine Deflection In Reduced Triaxial Extension Testing, Morgan Race May 2011

Effects Of Piston Uplift, Piston Friction, And Machine Deflection In Reduced Triaxial Extension Testing, Morgan Race

Civil Engineering Undergraduate Honors Theses

A series of Reduced Triaxial Extension (RTE) tests were conducted on dummy (brass) and null (water) samples to determine the effects of (corrections required for) piston uplift, piston friction and system compliance associated with RTE tests. During the consolidation stage of RTE tests, the sample may be consolidated in isotropic or anisotropic stress conditions. During the shearing stage of an RTE test, the sample is unloaded in the axial direction by decreasing the deviator stress while the radial stress remains constant. Ten (10) tests were conducted on a brass "dummy" sample. The device was assembled in the same manner as …


Impact Of Design Cost On Project Performance Of Design Bid Build Projects, Nirajan Mani May 2011

Impact Of Design Cost On Project Performance Of Design Bid Build Projects, Nirajan Mani

UNLV Theses, Dissertations, Professional Papers, and Capstones

The majority of public projects in the United States are procured and constructed by state or local governments using the design-bid-build (DBB) project delivery method. In the DBB method, the detailed design is completed by a design firm, then, a contractor builds the project according to the plans and specifications prepared by the design firm. Some studies show that a project's performance depends upon the quality of the design. If the errors in a design are minimized, the construction cost and schedule growth of the project also will be minimized.

This study analyzed data from Clark County, Nevada public works …


Economic Input–Output Life Cycle Assessment Of Water Reuse Strategies In Residential Buildings And Communities, Derek J. Gardels May 2011

Economic Input–Output Life Cycle Assessment Of Water Reuse Strategies In Residential Buildings And Communities, Derek J. Gardels

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

The objective of this study was to determine the environmental sustainability and economic feasibility of five water reuse designs using economic input-output life cycle assessments and benefit/cost analyses. These five water reuse designs were evaluated for four regions of the United States including the Northwest (Seattle), Southwest (Scottsdale), Midwest (Omaha), and Southeast (Tampa). The water reuse designs include a greywater reuse system with no treatment for sub-surface landscape irrigation for a single-family residential house (Model 1), an indoor greywater reuse system with treatment for toilet flushing and laundry washing for a single-family residential house (Model 2), a hybrid untreated greywater …


Probablistic Assessment Of Roof Uplift Capacities In Low-Rise Residential Construction, Bagyalakshmi Shanmugam May 2011

Probablistic Assessment Of Roof Uplift Capacities In Low-Rise Residential Construction, Bagyalakshmi Shanmugam

All Dissertations

Post hurricane damage investigations of light frame wood residential structures reveal that roof envelope failure induces considerable damage to the structure and its contents. Roof - to - wall (RTW) connection failures though not as common as roof sheathing failure also cause significant structural and material damage. Considerable changes have been made in the ASCE structural loads standard and International Building code (IBC) after hurricane Andrew in order to prevent RTW connection and sheathing failures. That includes not only a substantial increase in the design wind load in the past two decades but also a strict enforcement of tighter nailing …


A System Dynamics Approach For Climate Change Impact Analysis In The Snake River Basin, David Jerome Hoekema May 2011

A System Dynamics Approach For Climate Change Impact Analysis In The Snake River Basin, David Jerome Hoekema

Boise State University Theses and Dissertations

Warming temperatures throughout the Western United States due in part to human-induced climate change caused by the emission of greenhouse gases has been found to be responsible for 60% of the hydrologic change in the Western United States over the last half century. The hypothesis of the research is that climatic change will make planning and management based on historic climate conditions less reliable in the future. Therefore, there is a need for water management planning tools that capture feedback loops within the water-resource system so that management plans are developed that perform optimally under a wide array of inputs. …


Gis Based Pavement Maintenance: A Systematic Approach, Robert J. Kmetz Apr 2011

Gis Based Pavement Maintenance: A Systematic Approach, Robert J. Kmetz

Purdue Polytechnic Directed Projects

Abstract

According to 2008 Federal Highway Administration (FHWA) statistics, there are 2,734,102 miles of paved public roads in the United Sates, with an additional 1,324,245 miles of unpaved public roads.  Road conditions deteriorate with time as the result of weather effects, deicing salts, and vehicle loads.  The most common pavement distress includes cracking, rutting, and potholes.  These pavement defects must be repaired to restore the pavement to a satisfactory service level for road users. According to the FHWA, in 2006 approximately $54.2 billion dollars was spent on maintenance and expansion, just on U.S. highways alone.

Routine maintenance is a cost …


Effects Of Electromagnetic Stimulation On Soil’S Hydraulic Conductivity, Jonathan Rocha, Arvin Farid, Jim Browning Apr 2011

Effects Of Electromagnetic Stimulation On Soil’S Hydraulic Conductivity, Jonathan Rocha, Arvin Farid, Jim Browning

College of Engineering Poster Presentations

Our research involves the identification of the different effects that electromagnetic (EM) stimulation has on varying soil properties; properties such as hydraulic conductivity. This work could prove to be of importance in furthering our understanding of the effects of EM stimulation with regard to the hydraulic conductivity of soil. A positive correlation between EM stimulation and an increase in hydraulic conductivity could have broad applications for environmental contaminant mitigation in soils and for various geotechnical construction applications such as minimizing soil setup during pile driving operations. EM waves can be used to enhance soil and groundwater remediation in a way …


Development Of Approximating Functions To Model And Predict The Properties Of Fresh And Hardened Fly Ash-Based Geopolymer Concrete, Eleazar Ivan Diaz Loya Apr 2011

Development Of Approximating Functions To Model And Predict The Properties Of Fresh And Hardened Fly Ash-Based Geopolymer Concrete, Eleazar Ivan Diaz Loya

Doctoral Dissertations

The manuscript presented herein is based on the investigation of the mechanical properties of fly ash-based geopolymer concrete and their link to fly ash (FA) characteristics. A database of 32 FA samples was created. Each FA sample was analyzed in terms of chemical composition, crystallographic properties and particle size distribution. The mechanical performance of geopolymer concrete (GPC) made from each FA sample was evaluated in terms of density, setting time, compressive and flexural strength, static elastic modulus and Poisson's ratio. It is worth mentioning that the author has already published preliminary results of this study (Diaz and Allouche, 2010; Diaz …


Cottonwood Riparian Site Selection On The Cheyenne River Sioux Reservation, Julie A. Thorstenson, Diane Rickerl, Janet H. Gritzner Apr 2011

Cottonwood Riparian Site Selection On The Cheyenne River Sioux Reservation, Julie A. Thorstenson, Diane Rickerl, Janet H. Gritzner

Great Plains Research: A Journal of Natural and Social Sciences (through 2013)

The construction of the Oahe Dam on the Missouri River eliminated thousands of acres ofriparian and floodplain lands on the Cheyenne River Sioux Reservation in South Dakota. Restoration is needed to replace wildlife habitat. This study focused on site selection for native cottonwood (Populus deltoides Bartr. Ex Marsh. ssp. Monilifers (Ait.) Eckenwalde) restoration to help mitigate this loss. Geographic information systems technologies were used to develop a suitability model for cottonwood restoration. Tribal lands were extracted from a digital dataset oflandownership. Those touched by or included in a 46 m border of the Moreau River were candidate sites. Of …


The Solvent Effectiveness On Extraction Process Of Seaweed Pigment, Warkoyo Warkoyo, Elfi Anis Saati Apr 2011

The Solvent Effectiveness On Extraction Process Of Seaweed Pigment, Warkoyo Warkoyo, Elfi Anis Saati

Makara Journal of Technology

Eucheuma cottonii seaweed is a species of seaweed cultured in Indonesian waters, because its cultivation is relatively easy and inexpensive. It has a wide variety of colors from green to yellow green, gray, red and brown, indicating photosynthetic pigments, such as chlorophyll and carotenoids. An important factor in the effectiveness of pigment extraction is the choice of solvent. The correct type of solvent in the extraction method of specific natural materials is important so that a pigment with optimum quality that is also benefical to the society can be produced. The target of this research is to obtain a high …