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Full-Text Articles in Civil and Environmental Engineering

Erosion Behavior And Scour Risk Of Extremely Coarse Streambeds, Abolfazl Bayat Oct 2017

Erosion Behavior And Scour Risk Of Extremely Coarse Streambeds, Abolfazl Bayat

Dissertations

Bridge scour, which is the erosion of soil and rock around bridge abutments and piers, is the principal cause of bridge failure in the United States and around the world. Previous investigations of scour have focused mostly on fine sediments such as sand, silt, and small gravel, because such alluvium underlies a majority of bridges. The erosion resistance of coarser sediments has received limited attention to date, even though they dominate many small to medium-size rivers in the northern tiers of the United States, Europe, and Asia. This study focuses on the scour behavior of extremely coarse particles (ECP), namely …


Evaluating The Performance Of Contech's Stormfilter With Zpg Media Under The City Of Portland's 2016 Stormwater Management Manual Requirements For Manufactured Stormwater Treatment Technologies, Mawj T.H. Khammas Oct 2017

Evaluating The Performance Of Contech's Stormfilter With Zpg Media Under The City Of Portland's 2016 Stormwater Management Manual Requirements For Manufactured Stormwater Treatment Technologies, Mawj T.H. Khammas

Civil and Environmental Engineering Master's Project Reports

Stormwater runoff is the water generated from excess rainfall or snowmelt that flows over impervious surfaces such as paved roads, parking lots, and on roofs, it often carries a variety of pollutants that adversely affect water quality in that region. Portland is a well-developed city; the majority of the streets are paved and impervious and will consequently generate a tremendous amount of stormwater this creates the necessity for management to help preserve and mimic natural hydrologic cycle through improving water quality. The StormFilter® with ZPG media, manufactured by CONTECH, is a manufactured stormwater treatment technology(MSTT) in which zeolite, perlite, and …


A Comparative Study On The Durability Of Geopolymer Mortars Produced With Ground Glass Fiber, Fly Ash, And Glass-Powder In Sodium Sulfate Solution, Hassan Rashidian-Dezfouli, Prasada Rao Rangaraju Oct 2017

A Comparative Study On The Durability Of Geopolymer Mortars Produced With Ground Glass Fiber, Fly Ash, And Glass-Powder In Sodium Sulfate Solution, Hassan Rashidian-Dezfouli, Prasada Rao Rangaraju

Publications

An experimental investigation was conducted to investigate the performance of geopolymers made with three different precursors consisting of fly ash, Ground Glass Fiber (GGF), and Glass-Powder (GLP) exposed to sodium sulfate solution. Precursors were activated using either sodium hydroxide solution or combinations of sodium hydroxide and sodium silicate solution with varying levels of sodium and silica content. Among the mixtures with each of the three precursors, mortar mixtures with the highest compressive strength were selected to test their resistance against exposure to a 5% sodium sulfate solution. Changes in the weight and compressive strength of the specimens were monitored up …


Geopolitical Relations: Uganda’S Role In The Development Of The River Nile, Jordan Williams Oct 2017

Geopolitical Relations: Uganda’S Role In The Development Of The River Nile, Jordan Williams

Independent Study Project (ISP) Collection

This study examined the geopolitical relations of the Nile Basin by looking at Uganda as a case study, and analyzed Uganda’s use and development of the River Nile. It reviews the history of transboundary politics and treaties along with Uganda’s development projects in the region. The paper then discusses modern relations and agreements, with a focus on the most recent agreement between the Riparian States, the Cooperative Framework Agreement, and how Uganda fits into them with regards to their interest in hydropower development within their borders on the Nile. It then explores possible future developments on the river and the …


Reliability Analysis Of Active Earth Pressure For Cantilever Walls On Mudflows And Residual Soils Of The Aburrá Valley, Juan David Castro, Juan Camilo Viviescas, Juan Pablo Osorio Oct 2017

Reliability Analysis Of Active Earth Pressure For Cantilever Walls On Mudflows And Residual Soils Of The Aburrá Valley, Juan David Castro, Juan Camilo Viviescas, Juan Pablo Osorio

Conference papers

According to the variability of the local geology of the Aburrá Valley, two geological strata with similar grain size distribution were analyzed. The geologies are composed of mudflows and residual soils from the San Diego stock in the Poblado neighborhood. These soils show a similar mechanical behavior in relation to the number of blows of the standard penetration test SPT. The analysis was carried out by reliability methods for the determination of the active earth pressure for the geotechnical design of a cantilever walls. The analysis consists in the variation of the height of the retaining wall between 1 and …


A Picture Is Worth A Thousand Roads, Keith Pierce Oct 2017

A Picture Is Worth A Thousand Roads, Keith Pierce

News Items

No abstract provided.


Reliability Analysis Of Geosynthetic Reinforced Soil Walls, Michael Powers Oct 2017

Reliability Analysis Of Geosynthetic Reinforced Soil Walls, Michael Powers

Graduate Theses & Non-Theses

Geosynthetic reinforced soil walls have been widely used for earth retention and stabilization in many geotechnical applications. In the traditional design of geosynthetic reinforced soil walls, Allowable Stress Design (ASD) is used to address the uncertainties. However, it cannot explicitly consider the uncertainties in a systematic way in the design process; especially geotechnical uncertainties are typically at high levels and problem-specific. Traditional methods usually result in over-conservativeness, inconsistence, and empiricism in the design practice. Recently there has been a trend of the application of reliability methods for design of geosynthetic reinforced soil walls to explicitly address uncertainties in the design …


Performance-Based Contracting For Rest Area Maintenance, Michael Powers Oct 2017

Performance-Based Contracting For Rest Area Maintenance, Michael Powers

Graduate Theses & Non-Theses

To maintain rest area stops in the United States, three methods are used. They are the In-House method, Method-Based Contracting (MBC), and Performance-Based Contracting (PBC). In recent years, the PBC method has become increasingly popular because this method reduces the strain of managing In-House employees or MBC contracts, generates more business in the public sector, can increase the level of service (LOS), and generally reduces the costs of maintaining rest area stops up to 5%. In the United States, no less than 15 states use the PBC method to maintain their rest area stops, and the results from switching to …


Safety Concepts For Workers From An Osha Perspective, Zamaan Al-Shabbani, Roy E. Sturgill Jr., Gabriel B. Dadi Oct 2017

Safety Concepts For Workers From An Osha Perspective, Zamaan Al-Shabbani, Roy E. Sturgill Jr., Gabriel B. Dadi

Kentucky Transportation Center Research Report

Highway construction and maintenance workers face numerous hazards on job sites, many of which are unique by industry standards. Despite the exposure of state transportation agency employees and contractors to these hazards, there are few safety standards, regulations, programs that directly target the sector aimed at prevention and mitigation. To help the Kentucky Transportation Cabinet (KYTC) improve employee safety, researchers at the Kentucky Transportation Center (KTC) analyzed the frequency and causes of workplace injuries for 10 essential Cabinet maintenance operations. Most incidents were attributable to human factors or ergonomics. Based on this analysis, the leading causes of incidents, and a …


Understanding Sanitation Preferences: An Exploratory Study In The Sirohi District Of Rajasthan, Karen Mac Oct 2017

Understanding Sanitation Preferences: An Exploratory Study In The Sirohi District Of Rajasthan, Karen Mac

Independent Study Project (ISP) Collection

Of all the countries in the world, India has the highest number of people practicing open defecation, causing adverse health outcomes from the unconfined spread of faecal matter. The Government of India is ambitiously aiming to end this practice through the construction of 12 million toilets by 2019, but historically, many toilets across India have gone unused. This study focused on understanding: (1) the reasons why people continue to openly defecate despite having toilets and (2) the requirements of a toilet that rural households would be willing to use. Along with 36 observations of household toilets, semi-structured group (n=8) and …


Effects Of Vacuuming Pervious Concrete On Infiltration Rate, Demetrios E. Maurakis, Eugene G. Maurakis Oct 2017

Effects Of Vacuuming Pervious Concrete On Infiltration Rate, Demetrios E. Maurakis, Eugene G. Maurakis

Virginia Journal of Science

The objectives of this research were twofold: test the infiltration rate of pervious concrete before and after vacuum cleaning and assess infiltration variability over time. Infiltration tests were performed on a 558.2 m2 area of pervious concrete, divided into sixteen 0.35 m2 test areas in a parking area at the Science Museum of Virginia in Richmond, Virginia on five dates from November 4-December 30, 2013. Average infiltration rates (avg.= 22.8 and 36.3 L/m2/min) immediately after vacuuming were lower than those (avg.=30.7 and 41.3 L/m2/min) before vacuuming. We hypothesize that the vacuuming lifted materials towards the surface …


Geology Influence In The Slope Stability Analysis By Limit Equilibrium, Finite Elements And Random Finite Elements Methods, Juan Camilo Viviescas, Juan Pablo Osorio Oct 2017

Geology Influence In The Slope Stability Analysis By Limit Equilibrium, Finite Elements And Random Finite Elements Methods, Juan Camilo Viviescas, Juan Pablo Osorio

Conference papers

Slope stability analyzes correspond to the evaluation of the safety factors commonly performed through the limit equilibrium and finite element methods. Due to the uncertainty of the geotechnical parameters, different statistical methods have emerged such as the limit equilibrium combined with the Monte Carlo simulation method and the random finite elements, which have been widely accepted in recent years. Normally, these analyzes are not performed taking into account the geological influence on the geotechnical properties, so in this work we proceed with the comparison of several geometrical typologies of slopes for mudflows and a residual soils of the Stock San …


Elution Tailing Of Nonaqueous Phase Liquids In Porous Media, Louisa Orr Oct 2017

Elution Tailing Of Nonaqueous Phase Liquids In Porous Media, Louisa Orr

Civil and Environmental Engineering Undergraduate Honors Theses

A variety of porous media were studied to characterize contaminant dispersion over time. This work looked at a compilation of previously published studies to investigate the dependence of long term elution tailing trends on particular soil characteristics. Recession curve analysis was conducted on existing dispersed contaminant literature, to yield the low-concentration recession constant (K). The R2 values correlating the soil properties to contaminant concentration ranged from 0.12494 to 0.95429. The low-concentration recession constant (K) values ranged from 0.9745407 0.9999988. The relationship between K and the soil properties porosity, organic carbon, and fines fraction is increasing. Bulk density and the …


Chemical Variations And Engineering Implications Of Reclaimed Asphalt Pavement And Chemically Modified Asphalt Binders, Md Shahriar Al Alam Oct 2017

Chemical Variations And Engineering Implications Of Reclaimed Asphalt Pavement And Chemically Modified Asphalt Binders, Md Shahriar Al Alam

Student Theses and Dissertations

Petroleum crude oil, the prime source of asphalt binder, originates from many naturally occurring crude sources, which vary widely in chemical compositions. These compositions are defined as Saturates, Aromatics, Resins, and Asphaltenes (SARA) fractions. Physical properties of an asphalt binder are closely linked to its crude-inherited SARA fractions. Thus, asphalt binders differ significantly from one another, while they are intended to serve the same way under a specified traffic loading intensity and temperature. To serve this need, asphalt binders are often modified chemically. Sometimes, Reclaimed Asphalt Pavement (RAP) is added to this binder because of the limited supply of virgin …


Climate, Not Conflict, Explains Extreme Middle East Dust Storm, Anthony J. Parolari, Dan Li, Elie Bou-Zeid, Gabriel Katul, Shmuel Assouline Oct 2017

Climate, Not Conflict, Explains Extreme Middle East Dust Storm, Anthony J. Parolari, Dan Li, Elie Bou-Zeid, Gabriel Katul, Shmuel Assouline

Civil and Environmental Engineering Faculty Research and Publications

The recent dust storm in the Middle East (September 2015) was publicized in the media as a sign of an impending ‘Dust Bowl.’ Its severity, demonstrated by extreme aerosol optical depth in the atmosphere in the 99th percentile compared to historical data, was attributed to the ongoing regional conflict. However, surface meteorological and remote sensing data, as well as regional climate model simulations, support an alternative hypothesis: the historically unprecedented aridity played a more prominent role, as evidenced by unusual climatic and meteorological conditions prior to and during the storm. Remotely sensed normalized difference vegetation index demonstrates that vegetation cover …


Hydrologic Transport Of Dissolved Inorganic Carbon And Its Control On Chemical Weathering, Salvatore Calabrese, Anthony J. Parolari, Amilcare Porporato Oct 2017

Hydrologic Transport Of Dissolved Inorganic Carbon And Its Control On Chemical Weathering, Salvatore Calabrese, Anthony J. Parolari, Amilcare Porporato

Civil and Environmental Engineering Faculty Research and Publications

Chemical weathering is one of the major processes interacting with climate and tectonics to form clays, supply nutrients to soil microorganisms and plants, and sequester atmospheric CO2. Hydrology and dissolution kinetics have been emphasized as factors controlling chemical weathering rates. However, the interaction between hydrology and transport of dissolved inorganic carbon (DIC) in controlling weathering has received less attention. In this paper, we present an analytical model that couples subsurface water and chemical molar balance equations to analyze the roles of hydrology and DIC transport on chemical weathering. The balance equations form a dynamical system that fully determines …


The Bridge Newsletter Winter 2017, Missouri University Of Science And Technology Oct 2017

The Bridge Newsletter Winter 2017, Missouri University Of Science And Technology

The Bridge Newsletter

-Hands-on experience in concrete materials research and construction practices
-Making ACML progress
-Taos bridge project


Development Of A Performance-Based Procedure For Assessment Of Liquefaction-Induced Lateral Spread Displacements Using The Cone Penetration Test, Tyler Blaine Coutu Oct 2017

Development Of A Performance-Based Procedure For Assessment Of Liquefaction-Induced Lateral Spread Displacements Using The Cone Penetration Test, Tyler Blaine Coutu

Theses and Dissertations

Liquefaction-induced lateral spread displacements cause severe damage to infrastructure, resulting in large economic losses in affected regions. Predicting lateral spread displacements is an important aspect in any seismic analysis and design, and many different methods have been developed to accurately estimate these displacements. However, the inherent uncertainty in predicting seismic events, including the extent of liquefaction and its effects, makes it difficult to accurately estimate lateral spread displacements. Current conventional methods of predicting lateral spread displacements do not completely account for uncertainty, unlike a performance-based earthquake engineering (PBEE) approach that accounts for the all inherent uncertainty in seismic design. The …


An Investigation Into Isogeometric Blended Shells, David Scott Willoughby Oct 2017

An Investigation Into Isogeometric Blended Shells, David Scott Willoughby

Theses and Dissertations

Improvements to isogeometric blended shells are introduced which blend traditional Reissner-Mindlin shells, and Kirchhoff-Love shells, with an exact interpolation of the shell director increment. A gradient extraction operator is introduced which allows derivatives of basis functions to be exactly expressed as a linear combination of the basis functions themselves. Several benchmarks are investigated and the new blended shell is compared with different shell elements in ABAQUS and NASTRAN. In addition, the effect of different quadrature schemes is included in the comparisons. The new isogeometric blended shell performs comparably in some benchmarks, and even outperforms commercial shell finite elements in some …


Quantifying Pollutant Removal Rates Of Bioretention Basins As A Stormwater Best Management Practice, Evan Nathanial Waagen Oct 2017

Quantifying Pollutant Removal Rates Of Bioretention Basins As A Stormwater Best Management Practice, Evan Nathanial Waagen

Civil & Environmental Engineering Theses & Dissertations

Water pollution is an ongoing problem that can be attributed to human activities. As world population increases and countries become more developed, this problem intensifies. Fortunately, the causes and solutions of water pollution are documented and have been implemented with various levels of success. These solutions, or Best Management Practices (BMPs), vary in type and function and remove pollutants from runoff prior to it reaching rivers, lakes, and other bodies of water. This study investigates bioretention basins, a specific group of BMPs, and presents analysis and prediction of their performance, of which our knowledge is incomplete in the existing literature. …


Holistic Approach In Microalgae Conversion To Bioproducts And Biofuels Through Flash Hydrolysis, Ali Teymouri Oct 2017

Holistic Approach In Microalgae Conversion To Bioproducts And Biofuels Through Flash Hydrolysis, Ali Teymouri

Civil & Environmental Engineering Theses & Dissertations

In recent years, the demand for renewable energy, mainly biomass has increased. The U.S. Energy Information Administration reported that more than 13.3% of the total energy production in the first seven months of 2017 was produced from a biomass source. Among all biomass resources, microalgae has brought a lot of attention due to their numerous advantages such as higher growth rate and productivity compared with the conventional energy crops, higher energy conversion efficiency by photosynthesis, and less water requirement than terrestrial crops. However, its development is far behind industrial production. Several research efforts across the globe have been concerned with …


Eulerian-Based Virtual Visual Sensors To Measure Dynamic Displacements Of Structures, Ali Shariati, Thomas Schumacher Oct 2017

Eulerian-Based Virtual Visual Sensors To Measure Dynamic Displacements Of Structures, Ali Shariati, Thomas Schumacher

Civil and Environmental Engineering Faculty Publications and Presentations

Vibration measurements provide useful information about a structural system's dynamic characteristics and are used in many fields of science and engineering. Here, we present an alternative noncontact approach to measure dynamic displacements of structural systems using digital videos. The concept is that intensity measured at a pixel with a fixed (or Eulerian) coordinate in a digital video can be regarded as a virtual visual sensor. The pixels in the vicinity of the boundary of a vibrating structural element contain useful frequency information, which we have been able to demonstrate in earlier studies. Our ultimate goal, however, is to be able …


Effects Of Nitrogen And Phosphorus Fertilizer And Topsoil Amendment On Native Plant Cover In Roadside Revegetation Projects, Heidi L. Hillhouse, Walter H. Schacht, Jonathan M. Soper, Carol E. Wienhold Oct 2017

Effects Of Nitrogen And Phosphorus Fertilizer And Topsoil Amendment On Native Plant Cover In Roadside Revegetation Projects, Heidi L. Hillhouse, Walter H. Schacht, Jonathan M. Soper, Carol E. Wienhold

Department of Agronomy and Horticulture: Faculty Publications

Establishing vegetation on roadsides following construction can be challenging, especially for relatively slow growing native species. Topsoil is generally removed during construction, and the surface soil following construction (“cut-slope soils”) is often compacted and low in nutrients, providing poor growing conditions for vegetation. Nebraska Department of Transportation (NDOT) protocols have historically called for nitrogen (N) and phosphorus (P) fertilization when planting roadside vegetation following construction, but these recommendations were developed for cool-season grass plantings and most current plantings use slower-establishing, native warmseason grasses that may benefit less than expected from current planting protocols. We evaluated the effects of nitrogen and …


An Abbreviated Leap: The Geopolitical And Geoeconomic Significance Of The China – Pakistan Economic Corridor To The New Silk Road, Emma Nichols Oct 2017

An Abbreviated Leap: The Geopolitical And Geoeconomic Significance Of The China – Pakistan Economic Corridor To The New Silk Road, Emma Nichols

Independent Study Project (ISP) Collection

The objective of this analysis is to reveal the geopolitical and geoeconomic significance of the China – Pakistan Economic Corridor of the Belt and Road Initiative to its major stakeholders; Pakistan and China. In 2013, Chinese President Xi Jinping unveiled one of the most ambitious international infrastructure plans in modern history. The plan, in its earliest stages, is currently underway with its first portion, the China – Pakistan Economic Corridor (CPEC). Through careful preliminary analysis of the greater Belt and Road Initiative, the China – Pakistan Economic Corridor, and history of Sino-Pak relations, the motivations of the collaborating nations are …


The Professional Constructor, Full Issue, Volume 42, Number 02 Oct 2017

The Professional Constructor, Full Issue, Volume 42, Number 02

The Professional Constructor

No abstract provided.


Increased Span Length For The Mgs Long-Span Guardrail System Part Iii: Failure Analysis, Sagheer A. Ranjha, Robert W. Bielenberg, John D. Reid, Ronald K. Faller Sep 2017

Increased Span Length For The Mgs Long-Span Guardrail System Part Iii: Failure Analysis, Sagheer A. Ranjha, Robert W. Bielenberg, John D. Reid, Ronald K. Faller

Nebraska Department of Transportation: Research Reports

The objective of this research study was to review and analyze the system failure observed during crash testing of an increased span length for the MGS long-span guardrail system in test no. MGSLS-2. Test no. MGSLS-2 was a full-scale crash test conducted on the MGS long-span guardrail with a span length of 311⁄4 ft (9.5 m). This test utilized universal breakaway steel posts (UBSPs) adjacent to the long span in lieu of the controlled release terminal (CRT) wood posts used in previous long span systems.

An engineering analysis was undertaken to review the downstream end anchorage failure observed in test …


The Shifting Discourse On Third Places: Ideological Implications, Mark N. Wexler, Judy Oberlander Sep 2017

The Shifting Discourse On Third Places: Ideological Implications, Mark N. Wexler, Judy Oberlander

Journal of Ideology

Within the social sciences, literature on third places attempts to assist in the construction of a social concept of “place”. This notion of a place is an idealization of the bridging space with home and family on one side, and work with the rule-based impersonality of life in mass society, on the other. Like the idea of work-life balance—as seen through the vocabulary of placemaking—third places provide people with a place in which there is a balance between the emotive attachments of home and family and the challenge striving for merit and reward in the marketplace. To date, third places …


Lab-On-Sensor For Structural Behavior Monitoring: Theory And Applications, Genda Chen Sep 2017

Lab-On-Sensor For Structural Behavior Monitoring: Theory And Applications, Genda Chen

INSPIRE Archived Webinars

There are over 600,000 bridges in the U.S. National Bridge Inventory (NBI). Nearly 50% of them rapidly approach their design life and deteriorate at an alarming rate, particularly under an increasing volume of overweight trucks. Visual inspection as the current practice in bridge management is labor intensive and subjective, resulting in inconsistent and less reliable element ratings. Lab-on-sensor technologies can provide supplemental mission-critical data to the visual inspection for both qualitative and quantitative evaluations of structural conditions, and thus critical decision-making of cost-effective strategies in bridge preservation.

In this presentation, the design and operation characteristics of highway bridges are first …


A Comparative Life Cycle Assessment Between A Metered Dose Inhaler And Electric Nebulizer, Brandon Goulet, Lars E. Olson, Brooke K. Mayer Sep 2017

A Comparative Life Cycle Assessment Between A Metered Dose Inhaler And Electric Nebulizer, Brandon Goulet, Lars E. Olson, Brooke K. Mayer

Civil and Environmental Engineering Faculty Research and Publications

Life cycle assessment (LCA) evaluates the environmental impact of a product based on the materials and processes used to manufacture the item as well as the item’s use and disposal. The objective of this LCA was to evaluate and compare the environmental impact of a metered dose inhaler, specifically the Proventil® HFA inhaler (Merk & Co., Inc., Kenilworth, NJ, USA), and an electric nebulizer, specifically the DeVilbiss Pulmo-Aide® nebulizer (DeVilbiss, Port Washington, NY, USA). GaBi LCA software was used to model the global warming potential (GWP) of each product by using substantiated data and well-justified assumptions for the components, manufacturing, …


Boom And Bust Carbon-Nitrogen Dynamics During Reforestation, Anthony J. Parolari, Megan L. Mobley, Allan R. Bacon, Gabriel Katul, Daniel Deb. Richter, Amilcare Porporato Sep 2017

Boom And Bust Carbon-Nitrogen Dynamics During Reforestation, Anthony J. Parolari, Megan L. Mobley, Allan R. Bacon, Gabriel Katul, Daniel Deb. Richter, Amilcare Porporato

Civil and Environmental Engineering Faculty Research and Publications

Legacies of historical land use strongly shape contemporary ecosystem dynamics. In old-field secondary forests, tree growth embodies a legacy of soil changes affected by previous cultivation. Three patterns of biomass accumulation during reforestation have been hypothesized previously, including monotonic to steady state, non-monotonic with a single peak then decay to steady state, and multiple oscillations around the steady state. In this paper, the conditions leading to the emergence of these patterns is analyzed. Using observations and models, we demonstrate that divergent reforestation patterns can be explained by contrasting time-scales in ecosystem carbon-nitrogen cycles that are influenced by land use legacies. …