Civil and Environmental Engineering Commons^™

An Analysis Of Energy Consumption And The Use Of Renewables For A Small Drinking Water Treatment Plant, Saria Bukhary, Jacimara Batista, Sajjad Ahmad

Civil and Environmental Engineering and Construction Faculty Research

One of the pressing issues currently faced by the water industry is incorporating sustainability considerations into design practice and reducing the carbon emissions of energy-intensive processes. Water treatment, an indispensable step for safeguarding public health, is an energy-intensive process. The purpose of this study was to analyze the energy consumption of an existing drinking water treatment plant (DWTP), then conduct a modeling study for using photovoltaics (PVs) to offset that energy consumption, and thus reduce emissions. The selected plant, located in southwestern United States, treats 0.425 m3 of groundwater per second by utilizing the processes of coagulation, filtration, and disinfection. …

Treatment Of Perchlorate And Multiple Oxyanions: Chemical And Biological Investigations, Mark Elkouz

UNLV Theses, Dissertations, Professional Papers, and Capstones

Groundwater contamination with oxyanions is an issue that must be addressed for environmental, ecological and societal reasons. Chemical and biological treatment methods of reduction are already known and practiced, but the simultaneous presence of multiple oxyanions can add complicating effects to treatment sequence and efficacy. This research was concerned with the investigation of the chemical reductive treatment of Cr(VI) using both calcium polysulfide (CaSx) and ferrous sulfate (FeSO4), and the biological reductive treatment of chlorate, Cr(VI), nitrate and perchlorate using multiple organic substrates. The chemical treatment phase consisted of initial jar tests, using CaSx and FeSO4, followed by a laboratory …

Development Of Natural Perlite Based Concrete For Sustainable Construction, Seyedmahmoud Motaharikarein

UNLV Theses, Dissertations, Professional Papers, and Capstones

This study aimed to partially replace Portland Cement (PC) with environmentally friendly binders capable of improving the longevity of concrete. The new binders consisted of different proportions of natural pozzolan (perlite) with various fineness and particle size distributions. A step-by-step research program was designed to: (1) discover the optimum fineness of perlite powder and its optimum replacement level with cement; (2) investigate the rheological properties of the perlite-containing mixtures, and examine whether this binder can be used in selfconsolidating concrete; and (3) assess the weaknesses of the new binder, and improve its deficiencies by using nanomaterials such as nano-silica. The …

Sizing A New Bike Sharing System For The University Of Nevada, Las Vegas, Nesley Orochena

UNLV Theses, Dissertations, Professional Papers, and Capstones

The strategic planning objectives for a novel Bike Sharing Systems (BSS) are to locate the BSS stations, size the stations, and determine the bicycle fleet size, among others. Current guidelines to design BSS programs are tailored to city centers with large coverage areas and high bicycle to population ratios, and thus not directly transferable to a university setting. An ordered probit model was created using data from a university online stated preference survey to determine the key factors that affect the uptake rates for the UNLV BSS program and to estimate the potential demand. The demand analysis was incorporated into …

Galena Creek Bridge Structural Health Monitoring Instrumentation And Modeling, Leopold Falkensammer

UNLV Theses, Dissertations, Professional Papers, and Capstones

Structural health monitoring (SHM) of an instrumented structure provides numerous benefits when assessing the long-term condition of the structure against degradation, or the short-term condition after an extreme event, such as an earthquake. The Nevada Department of Transportation (NDOT) has an interest in expanding the use of SHM for such assessments. Accordingly, the objective of the current study is to develop and implement a permanent SHM system for the Galena Creek Bridge, the largest concrete cathedral arch bridge in the world, to monitor its response to routine traffic and seismic activity. Completed in 2012, the bridge connects Reno and Carson …

Utility Of Bench Scale Sand Tank Experiments At Assessing Permeable Reactive Barrier Design, Brandon Meier

UNLV Theses, Dissertations, Professional Papers, and Capstones

The objective of this work was to evaluate the utility of bench scale sand tank experiments at assessing permeable reactive barrier (PRB) design. Our criteria for meeting this goal was that differences between PRB designs could be identified solely by measuring concentration in outflow from the sand tank models. For our PRB designs (funnel-and-gate, staggered wells, and parallel bars), numerical simulations clearly showed that PRB design had a quantifiable effect on outflow concentration, provided that the solute reacted with the PRB materials. Conversely, use of a conservative (non-reactive) solute did not allow us to discern between PRB design alternatives. Employing …

Design Of Efficient Carbon-Based Adsorbents For The Removal Of Organic And Inorganic Water Contaminants, Sayedeh Soroosh Mortazavian Dehkordi

UNLV Theses, Dissertations, Professional Papers, and Capstones

Granular activated carbon (AC) and biochar (BC) are two carbon-based adsorbents commonly used for water and wastewater treatment. However, these adsorbents have drawbacks that suppress their aqueous contaminants removal efficiency. Their major disadvantages are that AC has low selectivity and reusability potential, and BC has a hydrophobic nature.

The scope of this dissertation is to enhance the performance of commonly-used carbon-based adsorbents for the removal of organic and inorganic water contaminants and to understand the interactive mechanism of contaminants’ ions/molecules with adsorbents. Hexavalent chromium (Cr(VI)) and trichloroethylene (TCE) are two types of inorganic and organic water contaminants, respectively, which are …

Evaluation Of Titanosilicate Materials For The Sorption Of Cesium And Strontium From High Level Wastes, Matheus Tolentino Lauar

UNLV Theses, Dissertations, Professional Papers, and Capstones

Treatment of high-level waste (HLW) stored in the U.S. Department of Energy (U.S. DOE) sites of Hanford and Savannah River involves the separation of radioactive cesium (137Cs) and strontium (90Sr). Challenges in treating the liquid HLW includes high alkalinity or acidity, and high salt content, many orders of magnitude above Cs and Sr concentrations. Ion exchange is the preferred process for removing these compounds, due to the availability of selective media and large volume-processing capacity by column operations. The crystalline silicotitanate (Na2Ti2O3SiO4·2H2O), i.e. CST, which structure is analog to the mineral sitinakite, is considered the reference material for this application. …

Examining The Effectiveness Of A 4d Schedule And A Virtual Reality Model On A Modular Project: Unlv Solar Decathlon Case, Rajarshi Ghimire

UNLV Theses, Dissertations, Professional Papers, and Capstones

The use of a 4D schedule as technological advancement has brought significant improvement to the planning and execution of construction projects, through visualizing stepwise construction progress, following a sequence of pre-planned activities, and finalizing a baseline schedule with necessary changes. Moreover, the application of virtual reality (VR) to create interactive 3D models of a planned structure has made it possible to make a detailed planning of any construction project. Because of these benefits, the use of 4D schedules and VR in the construction industry has increased drastically, leading to improved planning and execution. However, past studies have given little attention …

Impact Of Design Cost Percentage On Cost Growth, Schedule Growth, And Construction Intensity Of Road Construction Projects, Elina Prajapati

UNLV Theses, Dissertations, Professional Papers, and Capstones

The performance of construction projects is measured in terms of cost and schedule variation. Studies have identified that such variations are mainly due to design changes, which are more frequent on projects executed through the design-bid-build (DBB) delivery method. Thus, the design factor is identified as one of the major parameters affecting the performance of DBB projects. Despite the majority of road projects being constructed following the DBB method, the impact of design cost on the performance of road projects has not been sufficiently studied yet. Therefore, this study focuses on determining the effect of design cost on the performance …

Carbon Management And Volatile Fatty Acid Production In Primary Clarifiers At A Wastewater Treatment Plant, Brittany Nicole Radke

UNLV Theses, Dissertations, Professional Papers, and Capstones

An increasing number of treatment plants are required to remove nutrients from domestic wastewater to lessen the impact of nutrient loading to water bodies. Enhanced Biological Phosphorus Removal (EBPR) is one of the processes commonly used to remove phosphorus from domestic wastewater. The presence of an adequate quantity of volatile fatty acids (VFA) in the wastewater influent to EBPR is important for process efficiency and stability. The objective of this research was to investigate the production of VFAs through fermentation of sludge in primary clarifiers as it related to improving nutrient removal, primarily targeting phosphorus.

The research tested, in full-scale, …

Application Of Data-Driven And Process-Based Modeling Approaches For Water Quality Simulation In Lakes And Freshwater Reservoirs, Ali Saber Sichani

UNLV Theses, Dissertations, Professional Papers, and Capstones

Lakes and freshwater reservoirs often serve as the primary drinking and irrigation water sources for surrounding communities. They provide recreational and tourism opportunities, thereby promoting the prosperity of neighboring communities. Reliable estimates of water quality in lakes and reservoirs can improve management practices to protect water resources.

Seasonal water temperature and solar shortwave radiation variations, and their subsequent interactions with water column aquatic life, combined with seasonal variations of mixing intensity throughout the water column, result in variations of water quality constituents with depth during the annual cycle. The complexity of these variations entails the use of advanced water quality …

Alkali-Silica Reactivity Of Mortars Containing Natural Pozzolan, Arash Kian

UNLV Theses, Dissertations, Professional Papers, and Capstones

Alkali-silica reactivity is one of the most recognized deleterious phenomena in Portland cement concrete resulting in cracks, spalling, and other deleterious mechanisms.

The aim of this study was (i) to assess the extent of reactivity of the aggregates, quarried from seven different sources, suspected of being conducive to ASR, and (ii) to compare the effectiveness of industrial (Class F fly ash) and natural pozzolans in mitigation of alkali-silica reactivity of the studied aggregates. To this end, seven aggregate sources, four natural pozzolan sources, and one source of Class F fly ash were used. ASTM Type V Portland cement was replaced …

Bringing Statistical Learning Machines Together For Hydro-Climatological Predictions - Case Study For Sacramento San Joaquin River Basin, California, Balbhadra Thakur, Ajay Kalra, Sajjad Ahmad, Kenneth W. Lamb, Venkat Lakshmi

Civil and Environmental Engineering and Construction Faculty Research

Study region: Sacramento San Joaquin River Basin, California Study focus: The study forecasts the streamflow at a regional scale within SSJ river basin with largescale climate variables. The proposed approach eliminates the bias resulting from predefined indices at regional scale. The study was performed for eight unimpaired streamflow stations from 1962–2016. First, the Singular Valued Decomposition (SVD) teleconnections of the streamflow corresponding to 500 mbar geopotential height, sea surface temperature, 500 mbar specific humidity (SHUM500), and 500 mbar U-wind (U500) were obtained. Second, the skillful SVD teleconnections were screened non-parametrically. Finally, the screened teleconnections were used as the streamflow predictors …

College Of Engineering Senior Design Competition Fall 2019, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Part of every UNLV engineering student’s academic experience, the senior design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. A capstone to the student’s educational career, the senior design project encourages the student to use everything learned in the engineering program to create a practical, real world solution to an engineering challenge. The senior design competition helps focus the senior students in increasing the quality and potential for commercial application for their design projects. Judges from local industry evaluate the projects on …

Design And Preliminary Testing Of Demand-Responsive Transverse Rumble Strips, Md Shakhawat Hossen, Christopher Kappes, Mohamed Trabia, Brendan Morris, Jeewoong Park, Alexander Paz

Mechanical Engineering Faculty Research

Transverse rumble strips are common practice to alert drivers by engaging their auditory and tactile senses in addition to visual senses by traffic signals. However, continuous exposure to noise and vibration by transverse rumble strips often results in diminished effectiveness and erratic behaviors, leading to additional safety challenges. In response, demand-responsive transverse rumble strips were developed as traffic safety countermeasures that reduce unnecessary noise and vibration associated with transverse rumble strips by incorporating active control of the rumble strips. Rather than staying static, demand-responsive transverse rumble strips are activated based on the presence of pedestrians, at predesignated times, or in …

Melpf Version 1: Modeling Error Learning Based Post-Processor Framework For Hydrologic Models Accuracy Improvement, Rui Wu, Lei Yang, Chao Chen, Sajjad Ahmad, Sergiu M. Dascalu, Frederick C. Harris Jr.

Civil and Environmental Engineering and Construction Faculty Research

This paper studies how to improve the accuracy of hydrologic models using machine-learning models as post-processors and presents possibilities to reduce the workload to create an accurate hydrologic model by removing the calibration step. It is often challenging to develop an accurate hydrologic model due to the time-consuming model calibration procedure and the nonstationarity of hydrologic data. Our findings show that the errors of hydrologic models are correlated with model inputs. Thus motivated, we propose a modeling-error-learning-based post-processor framework by leveraging this correlation to improve the accuracy of a hydrologic model. The key idea is to predict the differences (errors) …

Rheological Properties Of Modified Crumb Rubber Asphalt Binder And Selecting The Best Modified Binder Using Ahp Method, Mehdi Khalili, Kazem Jadidi, Serji Amirkhanian

Civil and Environmental Engineering and Construction Faculty Research

Crumb rubber modifier (CRM) is one of the most popular asphalt binder modifiers due to the economic benefits and desired physical and rheological properties of asphalt binders and asphalt mixes. This research focuses on evaluating the properties of rubber-modified asphalt binders and selecting the best modified binder. The modified binders were produced by blending virgin binders with CRM at various contents of different gradations, and different methods of grinding. CRM made through ambient and cryogenic grinding methods with two gradation sizes were produced and tested. Three different virgin binders from two sources were obtained and used. The Analytic Hierarchy Process …

Investigation Of Efficiency Loss Of Distributed Solar Power Due To Soiling And Efficiency Recovery By Rainfall, Amanda Mayumi Tanaka

UNLV Theses, Dissertations, Professional Papers, and Capstones

As the concern with global warming increases causing the need for CO2 reduction, renewable energy is of great interest as it has lower carbon footprint when compared to conventional sources (natural gas, coal, oil and nuclear). Solar energy has been drawing worldwide attention since it can transform sunlight directly into electricity with the use of photovoltaic (PV) cells. However, this technology has some drawbacks that need to be addressed including dust deposition on solar panels, also known as soiling. Soiling can decrease PV panel’s efficiency thereby resulting in less energy production. The soiling rates are very site specific and depend …

The Effects Of Ventilation On Trihalomethanes Removal By Spray Aeration, Alicia Qiu Cheung

UNLV Theses, Dissertations, Professional Papers, and Capstones

Chlorination has been a vital and common step employed as a primary and/or secondary disinfectant to avoid outbreaks of waterborne diseases in drinking water supplies. Besides the desired effect of inactivating pathogens, chlorine also reacts with natural organic matter and precursors in raw water to form various carcinogenic disinfection by-products (DBPs), such as trihalomethanes (THMs), four of which are (represented as total trihalomethanes or TTHM) chloroform (CHCl3), dichlorobromomethane (CHCl2Br), chlorodibromomethane (CHClBr2), and bromoform (CHBr3). Spray aeration is an effective, economical, and suitable post-treatment method commonly employed in distribution systems (e.g., storage tanks) to remove these volatile organic compounds from the …

Bulbous Pier: An Alternative To Bridge Pier Extension As A Countermeasure Against Bridge Deck Splashing, Moses Karakouzian, Amilcar Chavez, Donald Hayes, Mohammad Nazari-Sharabian

Civil and Environmental Engineering and Construction Faculty Research

Bridge deck splashing causes deterioration to a bridge’s structure and renders the bridge unsafe for motorists and pedestrians. The traditional countermeasure for bridge deck splashing has been pier extension. Pier extensions move the pier wave and the associated splash away from the bridge deck, but retrofitting existing bridges with pier extensions is costly. This research evaluates the use of a bulbous added to the pier as an alternative to pier extension. A bulb placed on the upstream side of a bridge pier affects the splashing. The energy in the passing water is redirected from the impact by streamlining the flow. …

Development Of Threshold Levels And A Climate-Sensitivity Model Of The Hydrological Regime Of The High-Altitude Catchment Of The Western Himalayas, Pakistan, Muhammad Saifullah, Shiyin Liu, Adnan Ahmad Tahir, Muhammad Zaman, Sajjad Ahmad, Muhammad Adnan, Dianyu Chen, Muhammad Ashraf, Asif Mehmood

Civil and Environmental Engineering and Construction Faculty Research

Water shortages in Pakistan are among the most severe in the world, and its water resources are decreasing significantly due to the prevailing hydro-meteorological conditions. We assessed variations in meteorological and hydrological variables using innovative trend analysis (ITA) and traditional trend analysis methods at a practical significance level, which is also of practical interest. We developed threshold levels of hydrological variables and developed a non-parametric climate-sensitivity model of the high-altitude catchment of the western Himalayas. The runoff of Zone I decreased, while the temperature increased and the precipitation increased significantly. In Zone II, the runoff and temperature increased but the …

Effect Of Overburden Height On Hydraulic Fracturing Of Concrete-Lined Pressure Tunnels Excavated In Intact Rock: A Numerical Study, Moses Karakouzian, Mohammad Nazari-Sharabian, Mehrdad Karami

Civil and Environmental Engineering and Construction Faculty Research

: This study investigated the impact of overburden height on the hydraulic fracturing of a concrete-lined pressure tunnel, excavated in intact rock, under steady-state and transient-state conditions. Moreover, the Norwegian design criterion that only suggests increasing the overburden height as a countermeasure against hydraulic fracturing was evaluated. The Mohr–Coulomb failure criterion was implemented to investigate failure in the rock elements adjacent to the lining. A pressure tunnel with an inner diameter of 3.6 m was modeled in Abaqus Finite Element Analysis (FEA), using the finite element method (FEM). It was assumed that transient pressures occur inside the tunnel due to …

Investigation Of Tactile Sensory System Configuration For Construction Hazard Perception, Sayan Sakhakarmi, Jeewoong Park

Civil and Environmental Engineering and Construction Faculty Research

The application of tactile-based wearable devices to assist in navigation for people with low sight/low memory has demonstrated the feasibility of using such devices as a means of communication. Accordingly, a previous study in construction research investigated various parameters of tactile signals to develop a communicable system for potential application in construction hazard communication. However, the nature of construction limits the application of such devices to the body of construction workers, and it is important to understand sensor design parameters for improved communication, which has not been given significant attention yet. Therefore, this study aims to determine key design factors …

A New Uav-Based Module Lifting And Transporting Method: Advantages And Challenges, Jin Choi, Dong Bin Kim

Civil and Environmental Engineering and Construction Faculty Research

The modular construction technique is the one key technology that can substantially advance the competitiveness of the construction industry. However, the industry is having difficulty creating an optimum environment for broader and more effective use of modularization due to one key barrier: implementing a modular construction technique, that is, shipping modules from the fabrication shop to the build site. Multiple issues are potentially challenging to overcome, such as module size and center of gravity, rigging, tie-down, site access, site congestion, and transportation regulations, as well as the availability of local heavy lift equipment. The researchers propose to implement drones as …

A Pilot Study Of Identifying Execution Plan Differences For Accelerated Bridge Construction, Jin Choi, Elina Prajapati

Civil and Environmental Engineering and Construction Faculty Research

Accelerated bridge construction (ABC) is an innovative construction technique used to accelerate the construction of new bridges, as well as the renovation/replacement of existing bridges. Due to the benefits offered by ABC, transportation authorities have a higher preference in executing an accelerated approach over conventional bridge construction. The execution of an accelerated approach has differences when compared to the conventional approach, and it is important to identify such differences for the successful implementation of ABC projects. However, there have been no studies to identify such execution differences. Therefore, this study was conducted to identify execution plan differences relevant to ABC. …

Calibrating Cii Rt283s Modularization Critical Success Factor Accomplishments, Jin Choi, James T. O’Connor, Young Hoon Kwak, Rajarshi Ghimire

Civil and Environmental Engineering and Construction Faculty Research

Modularization is a well-known construction technique where sections of the job are moved from on-site to a fabrication shop. Previously, the researchers identified the 21 most influential Critical Success Factors (CSFs) for successful modularization and quantified the degree of each CSF’s accomplishment by conducting a survey with 19 subject matter experts, and a case study with three modular projects. Through this methodology, the findings relied on the experience of experts. However, still missing from the understanding of modularization CSFs is a validation of the current degree of each CSF’s accomplishment by examining actual modular projects using a sufficient number of …

College Of Engineering Senior Design Competition Spring 2019, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Part of every UNLV engineering student’s academic experience, the senior design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. A capstone to the student’s educational career, the senior design project encourages the student to use everything learned in the engineering program to create a practical, real world solution to an engineering challenge. The senior design competition helps focus the senior students in increasing the quality and potential for commercial application for their design projects. Judges from local industry evaluate the projects on …

Opportunities And Challenges Of Modular Construction In A Hospitality Centric Environment, Shreyansh Paliwal

UNLV Theses, Dissertations, Professional Papers, and Capstones

Modular construction techniques can substantially decrease project schedules and costs, effectively maintaining or increasing the quality of an end product by shifting a percentage of site-based work to an off-site fabrication shop. Modular construction can also significantly contribute to sustainability by reducing site disruption, reducing waste generated, creating better relocatability and reusability, causing less dust and noise pollution, and reducing the probability of loss, theft, and damage to equipment. The primary goal of this research is to identify the opportunities and challenges of implementing modular construction techniques in a hospitality-centric environment, by investigating the current situation and characteristics of modular …

Modeling Driver-Pedestrian-Infrastructure Interactions At Signalized Midblock Crosswalks, Boniphace Kutela

UNLV Theses, Dissertations, Professional Papers, and Capstones

Cities and metropolitan areas are increasingly facilitating pedestrians’ movement by the provision of pedestrian walking facilities. As pedestrian traffic increases, the risk of crash involvement increases, especially at midblock locations, where pedestrians are exposed to unsafe interactions with vehicular traffic. To improve pedestrians’ safety at midblock locations, various countermeasures are provided, which include signalized crosswalks. Several studies have analyzed driver-pedestrian interactions, as well as pedestrian-infrastructure interactions at signalized midblock crosswalks. However, more in-depth studies are necessary, due to shortfalls of study assumptions, which have led to the application of improper statistical models, as seen in the literature. Improved models are …