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Full-Text Articles in Civil and Environmental Engineering

Examining Current State Of Practice Of Enhancing Visibility Of Winter Operations Vehicles, Wasiq Ameen May 2020

Examining Current State Of Practice Of Enhancing Visibility Of Winter Operations Vehicles, Wasiq Ameen

Civil Engineering Theses - Archive

Despite precautions taken by the operators of maintenance vehicles, insufficient visibility of winter operations vehicles cause many collisions in the United States. Numerous methods have been developed to enhance the visibility of winter operations vehicles. Although the visibility of winter operations vehicles has enhanced through these methods, the consistency in the implementation of the methods for enhancing their visibility is critical to avoid collisions. The inconsistencies in the implementation of the methods confuse the public who are traveling in winter conditions when visibility is low. The confusion leads to a delay in perception time and response time of the drivers …


Toward A Seismic Resistant Steel Staggered Truss Framing System (Stf), Ra'ed Al-Mazaidh May 2020

Toward A Seismic Resistant Steel Staggered Truss Framing System (Stf), Ra'ed Al-Mazaidh

Civil Engineering Dissertations - Archive

The Staggered Truss Framing (STF) system is a type of steel structural system used in mid- to high-rise buildings. It was initially developed in the 1960s in order to create a steel framing system that has low floor-to-floor height (9 to 10 ft.) and wide column-free space (60 to 80 ft.). This system consists of a series of story-high trusses spanning the total width between two rows of exterior columns and arranged in a staggered pattern on adjacent column lines. Due to the staggered layout, lateral seismic force transfer in the STF system is also in a staggered manner from …


High Salinity, High Concentration Perchlorate Reduction In The Presence Of Hexavalent Chromium, Nitrate, And Chlorate, Nicole Martin May 2020

High Salinity, High Concentration Perchlorate Reduction In The Presence Of Hexavalent Chromium, Nitrate, And Chlorate, Nicole Martin

UNLV Theses, Dissertations, Professional Papers, and Capstones

Perchlorate is a chemically stable anion which was used as an oxidizer in rocket propellant and explosives throughout the 1950’s and 1960’s. While natural sources of perchlorate exist, perchlorate in the environment is primarily a result of contamination from anthropogenic processes. Perchlorate contamination has now been identified in at least 45 states and is hazard to human health due to perchlorate’s ability to interfere with uptake of iodine in the thyroid gland. One of the most common and cost effective treatment methods for perchlorate remediation is biological reduction—utilizing bacteria to enzymatically reduce perchlorate into chloride and oxygen.

The purpose of …


A Hybrid Experimental-Numerical Study On The Flow Topology In The Confluence Hydrodynamics Zone Of An Open Channel With Lateral Drainage Pipe Discharge, Mohammad Nazari-Sharabian May 2020

A Hybrid Experimental-Numerical Study On The Flow Topology In The Confluence Hydrodynamics Zone Of An Open Channel With Lateral Drainage Pipe Discharge, Mohammad Nazari-Sharabian

UNLV Theses, Dissertations, Professional Papers, and Capstones

To avoid disrupting the flow in flood control channels with lateral drainage pipes, or impact channel capacity, confluences are constructed at small angles (Maximum 30○). These small angles are costly to construct, since they require more real estate than greater angles.

By performing several laboratory experiments in the Fluid Dynamics Laboratory of the University of Nevada, Las Vegas (UNLV) and utilizing a numerical model (FLOW-3D), this study investigated the impact of submerged lateral drainage pipe discharges into rectangular open channels, on flow topology in the confluence hydrodynamics zone (CHZ). This was done across a range of channel widths, flow rates, …


An Evaluation Of Bank Storage At Lake Mead Reservoir In The Southwest United States, Jon Woodrow Wilson May 2020

An Evaluation Of Bank Storage At Lake Mead Reservoir In The Southwest United States, Jon Woodrow Wilson

UNLV Theses, Dissertations, Professional Papers, and Capstones

A water balance model is employed at Lake Mead to monitor and verify changing hydrology that affects total volume at the reservoir. Bank storage, which is defined as the volume of water captured in permeable lithologic layers subject to changes induced by contact and proximity to an open waterbody, is one component that is updated regularly and is based upon data and methods that were developed in the 1960’s from observations made within the first 30 years of the reservoir's maturation. Since this period, the reservoir has undergone further development and a current understanding of additional hydrologic affects to bank …


Discovering Synergies Among Sustainable Rating Systems In Green Roof Analysis, Kanaan Hardaway May 2020

Discovering Synergies Among Sustainable Rating Systems In Green Roof Analysis, Kanaan Hardaway

Biological and Agricultural Engineering Undergraduate Honors Theses

As awareness has grown of the impacts the built environment has on the natural environment and the human psyche, methods to create more sustainable living environment have been developed. Green infrastructure is well-known for its environmental benefits. Emerging literature suggests green infrastructure have aesthetic qualities conducive to mental restoration, as well. To analyze the multi-benefits of green infrastructure, a green roof is studied for its aesthetic qualities and its impact on LEED, SITES, and WELL certification. A questionnaire was administered to individuals on the University of Arkansas campus to quantify human perceptions and attitudes toward a green roof on a …


Irrigation Design In Montana: Accommodating Varying Water Accessibility Across The Continental Divide., John Garrett Lampson May 2020

Irrigation Design In Montana: Accommodating Varying Water Accessibility Across The Continental Divide., John Garrett Lampson

Biological and Agricultural Engineering Undergraduate Honors Theses

The design work performed in this project was conducted over two summers (2018, 2019) of internship experience with the Natural Resources Conservation Service (NRCS) across the state of Montana. The first summer’s design work was based out of Glendive, MT, in Dawson County, approximately 50 kilometers from the North Dakota border. The second summer was in Missoula, MT, in Missoula County, near the Idaho border. The two areas differ significantly in topography, weather, and water availability with the main separating geographic influence being the Rocky Mountains.

This paper focuses on the design process and requirements for two farms located outside …


Development Of An In Vitro Intervertebral Disc Innervation Model To Screen Neuroinhibitory Biomaterials, Sarah M. Romereim, Caleb A. Johnston, Adan L. Redwine,, Rebecca A. Wachs May 2020

Development Of An In Vitro Intervertebral Disc Innervation Model To Screen Neuroinhibitory Biomaterials, Sarah M. Romereim, Caleb A. Johnston, Adan L. Redwine,, Rebecca A. Wachs

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Pain originating from an intervertebral disc (discogenic pain) is a major source of chronic low back pain. Pathological innervation of the disc by pain‐sensing nerve fibers is thought to be a key component of discogenic pain, so treatment with biomaterials that have the ability to inhibit neurite growth will greatly benefit novel disc therapeutics. Currently, disc therapeutic biomaterials are rarely screened for their ability to modulate nerve growth, mainly due to a lack of models to screen neuromodulation. To address this deficit, our lab has engineered a three dimensional in vitro disc innervation model that mimics the interface between primary …


Spherical Cavity Expansion Approach For The Study Of Rigid-Penetrator’S Impact Problems, Mario Buchely, Alejandro Marañon May 2020

Spherical Cavity Expansion Approach For The Study Of Rigid-Penetrator’S Impact Problems, Mario Buchely, Alejandro Marañon

Materials Science and Engineering Faculty Research & Creative Works

In recent years, Spherical Cavity Expansion (SCE) theory has been extensively utilized to model dynamic deformation processes related to indentation and penetration problems in many fields. In this review, the SCE theory is introduced by explaining the different mathematical features of this theory, its solution, and a potential application to model the penetration of a rigid penetrator into a deformable target. First, a chronologically literature review of the most common models used to study this kind of penetration problems is introduced, focusing on the SCE theory. Then, the engineering model of penetration is presented using the SCE approach. The model …


2020 Directory Of Indiana State, County, City And Town Officials Responsible For Road And Street Work, Indiana Ltap May 2020

2020 Directory Of Indiana State, County, City And Town Officials Responsible For Road And Street Work, Indiana Ltap

Indiana Local Technical Assistance Program (LTAP) Directory

Contact information for agency officials and employees responsible for Indiana’s local road infrastructure.


Bs News May/June May 2020

Bs News May/June

Building Services Engineering

No abstract provided.


Development Of Plane Rotating Traction System: Based On The High-Speed Rail (72+128+72) M Continuous Prestressed Concrete Beam Bridge, Weinan Wang May 2020

Development Of Plane Rotating Traction System: Based On The High-Speed Rail (72+128+72) M Continuous Prestressed Concrete Beam Bridge, Weinan Wang

Theses and Dissertations

With the advent of rotate construction techniques, it is easy to build a new bridge crossing over existing structures, rivers and valleys quickly, easily and safely. Although the general concept of the rotating method is similar for different engineering characteristics, it is necessary to make some changes, which are more in line with the requirements of the particular project. Based on a 3-spans (72+128+72)m continuous concrete bridge, this paper presents a new rotation method, the down-slide-way unbalanced rotation system, which can save time and reduce cost compared to the up-slide-way rotation method. Through the improvements of the traction system and …


Dewatering Of Chlorella Through Carbon Dioxide Hydrate Formation For Biofuel Production, Charles Dow May 2020

Dewatering Of Chlorella Through Carbon Dioxide Hydrate Formation For Biofuel Production, Charles Dow

Master's Theses

Renewable energy alternatives are currently of interest to meet ever-growing energy demands due to fossil fuel depletion and climate change. Biofuels, an alternative source, can be made from a range of organic matter. One option is algae, which can be grown without impacting food production and in a variety of conditions, however, the feasibility of converting algae into biofuel is of concern. Dewatering algae is a critical step in the process to make oil extraction more efficient. This study utilizes carbon dioxide clathrate hydrates as a novel process to dewater water saturated algae solutions. Clathrate hydrates are crystalline solids formed …


Pollution Prevention Via Recovery Of Cerium (Iv) Oxide In Optics Company, Eugene Park, William Gallagher, Sydor Optics, Flint Creek Resources May 2020

Pollution Prevention Via Recovery Of Cerium (Iv) Oxide In Optics Company, Eugene Park, William Gallagher, Sydor Optics, Flint Creek Resources

Articles

Pollution prevention methods were applied at an optics manufacturer in an effort to improve recovery of a valuable polishing component, cerium oxide (ceria), 77% of which was lost to dragout and sewer discharge. Centrifugation and microfiltratiion were evaluated to develop a process that would increase recovery of used ceria, which would then be sent back to the ceria supplier for reclamation and reuse. Full-scale implementation included a high-speed centrifuge that operates continuously with a microfiltration system through recirculation in a single process tank. Sydor Optics has improved ceria recovery from 23% to 48%, saving thousands of dollars annually.


Designing Technology For Different Scales Of Irrigation Scheduling, Paolo Alexander Consalvo May 2020

Designing Technology For Different Scales Of Irrigation Scheduling, Paolo Alexander Consalvo

Undergraduate Honors Capstone Projects

Uncertainty in water availability is a significant challenge to the agriculture industry. Farmers and irrigators depend on novel uses of sensors and data to maximize water efficiency. Documented studies have demonstrated scheduling irrigation is a straightforward, deterministic means of achieving water efficiency. Irrigation scheduling uses several parameters to determine the moment of crop water stress due to available water in the soil. However, sensors and data for soil moisture and matric potential, a parameter describing water available to plants, have the potential to train machine learning algorithms to forecast water irrigation needs based on previous measurements. Satellite remote-sensing is another …


Extremely Low Cycle Fatigue Behavior Of Additively Manufactured 17-4ph Stainless Steel, Kaley Collins May 2020

Extremely Low Cycle Fatigue Behavior Of Additively Manufactured 17-4ph Stainless Steel, Kaley Collins

Civil Engineering Undergraduate Honors Theses

Steel structures survive seismic loading thanks to components capable of dissipating large amounts of energy through large deformations. Future optimizations of these components include complex free-form geometries that are difficult to fabricate with traditional casting processes. Additive manufacturing (AM) is an alternative for producing optimized free-form geometries. AM material contains significant differences in microstructural characteristics and mechanical behavior compared to its wrought counterparts. Research has been conducted to understand the effect of microscopic features in the high cycle fatigue (HCF) and low cycle fatigue (LCF) regimes. This study focuses on the behavior of 17-4 Precipitation Hardening (PH) stainless steel in …


Multiaxial Fatigue Of Notched Steel Plates And Investigation Of Cfrp Retrofits For Crack Initiation Prevention, Ayumi Fujii May 2020

Multiaxial Fatigue Of Notched Steel Plates And Investigation Of Cfrp Retrofits For Crack Initiation Prevention, Ayumi Fujii

Civil Engineering Undergraduate Honors Theses

Fatigue cracks are cracks that result from repeated loading over time, often following millions of loading cycles. Fatigue cracks occur even if the applied load is not large enough to cause material yield. Once a fatigue crack initiates, resulting stress concentrations at the crack tip often make it difficult to arrest the growth of the crack. In order to prevent growth and propagation of fatigue cracks within structural components, it is necessary to alter the stress condition at the crack tip. Fatigue cracks in steel structures resulting from multiaxial loading and or geometry conditions that result in complex states of …


Preliminary Investigation Of Required Bsca Amount For Soil Cement Mixtures, Mariel Mayori Rivero May 2020

Preliminary Investigation Of Required Bsca Amount For Soil Cement Mixtures, Mariel Mayori Rivero

Civil Engineering Undergraduate Honors Theses

The recent increase of flooding in the United States and the high expenses related to the damage that these floods have caused to waterway structures suggests a potential interest in rapid setting soil cement to make effective repairs. For this thesis, mix designs of soil only at three different sand-clay proportions were prepared and tested for moisture content and maximum dry density. Due to the early closing of the laboratory and research activities, reliable results were collected from the 70% sand and 30% clay proportions. At those proportions of soil, the optimum moisture content was found to be 8.88% with …


Soil Moisture Content Determination By Means Of The Electromagnetic Spectrum, Julia Loshelder May 2020

Soil Moisture Content Determination By Means Of The Electromagnetic Spectrum, Julia Loshelder

Civil Engineering Undergraduate Honors Theses

Soil moisture content provides information about the strength, permeability, and compressibility of the soil under investigation. In the research described herein, the relationship between moisture content and reflectance values obtained from spectroscopy was developed to investigate whether in-situ moisture content can be determined in a faster and more efficient way than the current methods. The soil under investigation was laboratory-compacted kaolinite clay mixed with pyranine dye. These specimens were placed beneath an ultraviolet light and a halogen illuminator where reflectance values were collected over a 24-hour period. Correlations were developed from the following methods: 1) spectral indices, 2) continuum analyses …


Understanding Workability In Belitic Calcium Sulfoaluminate Concrete Mixtures, Caleb W. Chesnut May 2020

Understanding Workability In Belitic Calcium Sulfoaluminate Concrete Mixtures, Caleb W. Chesnut

Civil Engineering Undergraduate Honors Theses

Belitic Calcium Sulfoaluminate cement (BCSA) is an emerging technology in the concrete industry. BCSA has similar hardened properties to portland cement (PC) but can set in under 20 minutes and reach 4,000 psi in less than 2 hours. Portland cement accounts for 8% of the world’s CO2 emissions, BCSA cements require less energy to produce. Studies have shown that 40% less CO2 is emitted during the production of BCSA cement than portland cement. This environmental benefit also makes it a very promising PC alternative. Before a new material can be used, designers need to understand the material’s properties. The goal …


Countermeasures For Pedestrian-Involved Accidents On Interstate-Highways, Anna C. Hunter May 2020

Countermeasures For Pedestrian-Involved Accidents On Interstate-Highways, Anna C. Hunter

Civil Engineering Undergraduate Honors Theses

Pedestrian access to the Interstate is prohibited, but many pedestrian-involved accidents still occur on the Interstate in the United States. This project is a case study of West Memphis, Arkansas, which has the second highest occurrence of pedestrian-involved accidents on the Interstate in Arkansas. The study site location includes a segment of Interstate I-40 which is at- grade. The surrounding area contains several different land-uses, which is believed to be the primary generator of these accidents. The goal of this project is to determine the primary causes of these accidents and determine potential countermeasures to reduce the crash rate for …


Applying Performance Engineered Mixture Design To Permeable Concrete, Rachel Pohl May 2020

Applying Performance Engineered Mixture Design To Permeable Concrete, Rachel Pohl

Civil Engineering Undergraduate Honors Theses

The scope of research and application related to permeable pavements has recently broadened. The desire to significantly reduce the environmental impact of large paved areas makes the permeable pavement concept more desirable (American Concrete Institute, 2018). Although research and interest are increasing, the actual application of permeable pavement is still very limited and has not reached the airfield arena. In airfields, permeable pavement could possibly be used for aircraft aprons - which currently require substantial measures to control stormwater runoff. Permeable pavements are typically used in low-traffic-volume / lightly loaded applications; questions remain regarding a permeable pavement’s ability to hold …


Acoustic Sonolysis Of Antibiotics In Water, Natalie Pinon May 2020

Acoustic Sonolysis Of Antibiotics In Water, Natalie Pinon

UNLV Theses, Dissertations, Professional Papers, and Capstones

Antibiotic resistance is a prominent issue in the world today. It is said by the Centers for Disease Control and Prevention that it is one of the major public health challenges we face today. Predominantly, antibiotic resistance is growing because conventional wastewater treatment processes are not able to completely break down antibiotics. As bacteria are exposed to such antibiotics, which don’t kill them due to selective pressure, they become immune and develop resistance which is a huge health concern. To prevent this from occurring, antibiotics need to be removed from hospital wastewater. Sonication is a promising technology that can be …


Abiotic, Biotic, And Bio-Enhanced Reduction Of Hexavalent Chromium, Chloroform And Co-Contaminants Using Nano-Scale Zero Valent Iron In Highly Contaminated Groundwater, Eduardo Robleto Martinez May 2020

Abiotic, Biotic, And Bio-Enhanced Reduction Of Hexavalent Chromium, Chloroform And Co-Contaminants Using Nano-Scale Zero Valent Iron In Highly Contaminated Groundwater, Eduardo Robleto Martinez

UNLV Theses, Dissertations, Professional Papers, and Capstones

Investigations of groundwater in a former industrial perchlorate manufacturing site have shown high contamination with perchlorate, chlorate, nitrate, hexavalent chromium (Cr (VI)), and chloroform (CF) with levels greater than 3,000, 30,000, 300, 100, and 4 mg/L, respectively. Remediation efforts using biological reduction to desired contaminant levels at this site has been challenging due to high contaminant concentrations, and high total dissolved solids (TDS). Furthermore, removal of Cr(VI) and CF in the presence of nitrate, chlorate, and perchlorate has not been examined at the contaminated site. Nano-scale Zero-Valent-Iron (NZVI) has been effective at reducing groundwater contamination both with and without bacterial …


Nitrate And Herbicides Removal From Groundwater Using Immobilized Algae, Sara Mollamohammada May 2020

Nitrate And Herbicides Removal From Groundwater Using Immobilized Algae, Sara Mollamohammada

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

To improve crop yield and control broadleaf weeds, many farmers apply nitrate-based fertilizers and chemical herbicides to their fields. Excessive use of these chemicals can cause contamination in waterbodies and impact on the public health. The physical and chemical methods have been suggested to remove these herbicides are usually costly. In this study, the capability of immobilized algal beads in removing nitrate and several herbicides of environmental concern from synthetic and actual groundwater and surface water was evaluated.

The experiments were performed in batch, sequencing batch and continuous flow modes and the effect of different operational conditions (light intensity, cultivation …


Public-Private Partnership Contract Framework Development And Project Performance Analysis Compared To Design-Build In The Us Highway Projects, Medya Fathi May 2020

Public-Private Partnership Contract Framework Development And Project Performance Analysis Compared To Design-Build In The Us Highway Projects, Medya Fathi

UNLV Theses, Dissertations, Professional Papers, and Capstones

Construction projects can be delivered through various approaches; nevertheless, all practitioners and involved parties have a mutual goal, which is completing the project within the original scope, defined budget, and schedule. Reviewing the literature on public-private partnership (PPP), many efforts have been made covering different research areas, including policies, risks, roles and responsibilities, and finance. However, a study involving the development of a framework for PPP contracts, and quantitative assessment of project performance associated with PPP highway projects in the US is lacking. Therefore, this research fills such a noticeable gap in the body of knowledge on the PPP delivery …


Construction-Ready Digital Terrain Models, Rachel Catchings, Steven Waddle, Hala Nassereddine, Gabriel B. Dadi, Makram Bou Hatoum, Walter Johnson May 2020

Construction-Ready Digital Terrain Models, Rachel Catchings, Steven Waddle, Hala Nassereddine, Gabriel B. Dadi, Makram Bou Hatoum, Walter Johnson

Kentucky Transportation Center Research Report

Since 2009, Kentucky has made its 3D design data available as a supplemental reference to bidders through the project delivery process. This research discusses methods for ensuring electronic engineering data (EED) — and specifically the proposed digital terrain model (DTM) — support modern construction management methods at the Kentucky Transportation Cabinet (KYTC). Researchers performed a literature review, surveyed KYTC construction and design staff, engaged with Cabinet staff and industry members to understand the current state of practice, and evaluated quality- related attributes of the EED through case studies. The report presents a set of targeted recommendations for improving KYTC processes …


Ranchers Adapting To Climate Variability In The Upper Colorado River Basin, Utah, Hadia Akbar May 2020

Ranchers Adapting To Climate Variability In The Upper Colorado River Basin, Utah, Hadia Akbar

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Changes in climate influence agricultural production. This study looks at the impacts of climate variability in the Utah regions of the Upper Colorado River Basin by combining regression techniques with interview data to explore how climate variability affects agricultural production and how the farmers are adapting their practices to these changes. The results show that climate does not have any significant impact on cattle and hay production in the study area on a decadal scale. However, on an annual basis temperature seems to have more impact than precipitation. Among non-climatic variables, commodity prices and their regulations by the government are …


Pollution Prevention And Water Reuse At Utah Department Of Transportation Facilities, Amanda Stoudt May 2020

Pollution Prevention And Water Reuse At Utah Department Of Transportation Facilities, Amanda Stoudt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As stormwater flows over roads, sidewalks, and other impervious surfaces, it picks up pollutants that are deposited on these surfaces. One common pollutant transported by stormwater is road salt. While the application of road salt is crucial for wintertime public safety, road salt has a host of negative environmental impacts. Road salt has been linked to increasing levels of dissolved solids in groundwater, vegetation damage, and behavioral changes in aquatic organisms. Studies have shown that these impacts are concentrated around salt storage facilities. As a result, the United States Environmental Protection Agency issued many state departments of transportation municipal separate …


Strategic Infrastructure Planning For Autonomous Vehicles, Zhaocai Liu May 2020

Strategic Infrastructure Planning For Autonomous Vehicles, Zhaocai Liu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Compared with conventional human-driven vehicles (HVs), AVs have various potential benefits, such as increasing road capacity and lowering vehicular fuel consumption and emissions. Road infrastructure management, adaptation, and upgrade plays a key role in promoting the adoption and benefit realization of AVs. This dissertation investigated several strategic infrastructure planning problems for AVs. First, it studied the potential impact of AVs on the congestion patterns of transportation networks. Second, it investigated the strategic planning problem for a new form of managed lanes for autonomous vehicles, designated as autonomous-vehicle/toll lanes, which are freely accessible to autonomous vehicles while allowing human-driven vehicles to …