Civil and Environmental Engineering Commons^™

Thermophysical And Mechanical Properties Of Hardened Cement Paste With Microencapsulated Phase Change Materials For Energy Storage, Hongzhi Cui, Wenyu Liao, Shazim Ali Memon, Biqin Dong, Waiching Tang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In this research, structural-functional integrated cement-based materials were prepared by employing cement paste and a microencapsulated phase change material (MPCM) manufactured using urea-formaldehyde resin as the shell and paraffin as the core material. The encapsulation ratio of the MPCM could reach up to 91.21 wt%. Thermal energy storage cement pastes (TESCPs) incorporated with different MPCM contents (5%, 10%, 15%, 20% and 25% by weight of cement) were developed, and their thermal and mechanical properties were studied. The results showed that the total energy storage capacity of the hardened cement specimens with MPCM increased by up to 3.9-times compared with that …

Role Of Solids Retention Time On Complete Nitrification: Mechanistic Understanding And Modeling, Guoqiang Liu, Jianmin Wang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Effects of solids retention time (SRT) on both steps of the nitrification process (e.g., ammonia oxidation and nitrite oxidation) and the nitrifier community in a complete-mix activated sludge process were studied. At a SRT less than or equal to 20 days, the effluent ammonia concentration was lower than the effluent nitrite concentration. At the 40-day SRT, however, the effluent nitrite concentration became equal to or less than the effluent ammonia concentration. Quantitative Polymerase Chain Reaction (QPCR) assays indicated that increasing SRT significantly increased nitrite-oxidizing bacteria/ammonia-oxidizing bacteria (NOB/AOB) ratio. Further investigation indicated that Nitrosomonas europaea/eutropha were the dominant AOB for ammonia …

The Hydraulic Conductivity Structure Of Gravel-Dominated Vadose Zones Within Alluvial Floodplains, Ronald B. Miller, Derek M. Heeren, Garey A. Fox, Todd Halihan, Daniel E. Storm, Aaron R. Mittelstet

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The floodplains of many gravel-bed streams have a general stratigraphy that consists of a layer of topsoil covering gravel-dominated subsoil. Previous research has demonstrated that this stratigraphy can facilitate preferential groundwater flow through focused linear features, such as paleochannels, or gravelly regions within the vadose zone. These areas within the floodplain vadose zone may provide a route for interactions between the floodplain surface and alluvial groundwater, effectively extending the hyporheic zone across the floodplain during high stream stage. The objective of this research was to assess the structure and scale of texture heterogeneity within the vadose zone within the gravel …

Fly Ash As A Potential Scrubber Of Acidic Wastes From The Phosphate Industries In Israel, Roy Nir Lieberman, Eli Lederman, Ithamar Pelly, Haim Cohen

Coal Combustion and Gasification Products Journal Archive

Fly ash (FA) is produced in Israeli utilities via bituminous coal combustion. It is used as a cement additive or in concrete production, and its economic value is low. The FA produced in Israel is very basic (defined as class F) owing to ambient air quality standards that impose low sulfur content in the imported coals. Because the lime content is high (in the South African coal, ,10 wt%), it is a good potential chemical scrubber to acidic wastes. The phosphate industry in Israel produces mainly phosphate fertilizers and water-treatment products as well as phosphoric acid. The production methods rely …

Geochemistry And Mineralogy Of Coal-Fired Circulating Fluidized Bed Combustion Fly Ashes, Luis F.O. Silva, Marcos L.S. Oliveira, Rubens M. Kautzmann, Claudete G. Ramos, Maria Izquierdo, Shifeng Dai, Jennifer Wilcox, Jeremy Hoffman, James C. Hower

Coal Combustion and Gasification Products Journal Archive

The fuel, bed ash, and fly ash were sampled from a circulating fluidized bed combustion (CFBC) unit at two times. The first sampling was a high-sulfur (S) coal-only run, and the second sampling coincided with an experimental burn of up to 10% switchgrass (Panicum virgatum) pressed pellets mixed with a high-S coal. The latter blend had a higher moisture content and a lower heating value than the coal-only fuel. Given the time between the samplings and the special needs for the experimental run, unavoidable changes in the coal and limestone complicate comparisons of the bed ash and fly ash chemistry …

Study Of The Formation And Control Of Disinfection By-Products Originating From A Surface Water Supply On The Volcanic Island Of Guam, Erica Laberge

Electronic Theses and Dissertations

Three oxidants have been evaluated for use as alternative chemical pretreatments for Fena Lake, a surface water that supplies the U.S. Navy's Public Water System (PWS) on the volcanic island of Guam. The study consisted of two investigative components. The first and primary component included a bench-scale evaluation to study the effects of different pre-oxidant chemicals on the formation of chlorinated disinfection by-products (DBPs). The second and ancillary component included a series of water treatment and distribution system management studies that analyzed DBP formation within the treatment plant and water distribution system. The goal of this research was to reduce …

Transformation Of, In, And By Learning In A Service-Learning Faculty Fellows Program, Mary Cazzell, Shirley Theriot, Joan M. Blakey, Melanie L. Sattler

Civil Engineering Faculty Publications - Archive

Transformative learning is the most desired core outcome in adult education. The qualitative study examined critical reflections for professional transformation related to development and implementation of service-learning courses or projects from four university faculty members during enrollment in a Service-Learning Faculty Fellows program and post-servicelearning implementation. Reflective questions related to faculty perceptions of student learning, service-learning as pedagogy, and their own learning— transformation of, in, and by learning, respectively. Content analyses of faculty reflections resulted in three categories of transformation based on three preservice-learning and three post-servicelearning descriptive themes: (1) transformation of student learning from anticipatory integration to conflicts between …

Investigation Of An Association Between Childhood Leukemia Incidences And Airports In Texas, Sala. Nanyanzi Senkayi, Melanie L. Sattler, Nancy Rowe, Victoria Chen

Civil Engineering Faculty Publications - Archive

As worldwide demand for air travel increases, emissions from airports will likely also increase. Airport emissions pose a concern due to lack of information about their quantity and impacts on human health and the environment. This research aimed to address the question of whether there is an association between childhood leukemia cases and airport emissions in Texas. Rather than looking at the impacts of a single airport on the surrounding community, this study looks at all airports in the state of Texas, and 2 134 incidences of childhood leukemia (children age 9 and under) state–wide over a 10–year period. The …

Effect Of Enhanced Leachate Recirculated (Elr) Landfill Operation And Gas Extraction On Greenhouse Gas Emission, Sonia Samir

Civil Engineering Dissertations - Archive

The bioreactor/ enhanced leachate recirculated (ELR) landfill operation with the addition of moisture/ leachate to the landfill, accelerate the process of landfill waste decomposition; and increase the generation of LFG over a shorter period of time. Since emissions from the landfills are directly related to the gas generation, the increase in gas generation might also increase the emission from the landfill. On the contrary, the presence of gas extraction is suggested to mitigate the fugitive emissions from the landfills. Therefore, the motivation of the current study was to evaluate the effect of ELR operation as well as the gas extraction …

Estimation Of Optimum Compaction Level For Bioreactor Landfill Operation, Dipak Tiwari

Civil Engineering Dissertations - Archive

The effect of compaction on the degradation of MSW is important for the successful operation of bioreactor landfill. It has been a general tendency to compact working face solid waste as much as possible to gain more space. Previous studies has shown moisture content, moisture recirculation and ambient temperature were important components for degradation. There was a limitation on the compaction effect on degradation. Although several studies were conducted in the past to find the hydraulic conductivity of the waste, there was lack of work to find the optimum compaction to achieve sufficient flow inside the landfill and thus to …

Spatial Variability Models And Prediction Analysis Of Soil Properties Using Geostatistics, Tejo Vikash Bheemasetti

Civil Engineering Dissertations - Archive

Soils are composed of solid, water and air phases whose characteristics are highly variable. The interactions of these phases in the soil matrix can lead to different types of topographical formations and characteristics. Due to the uncertainty and complex interactions among these phases, studies on soils have always been a challenging problem for engineers. These variations and uncertainties make it necessary for engineers to adopt new techniques and methods to analyze soil properties in order to determine or interpret their generalized behaviors and patterns. Existing research in variability analysis tends to focus on the distribution of the soil properties, reliability-based …

Evaluation Of Lightweight Geofoam For Mitigating Bridge Approach Slab Settlements, Pinit Ruttanaporamakul

Civil Engineering Dissertations - Archive

The bump at the end of a bridge infrastructure is one of the frequent problems found in Texas and other states. Transportation agencies spend millions of dollars annually to repair the bump problem. The major cause of the problem is the settlement of backfill materials and foundation soils, as well as the erosion of backfill. Research was undertaken at the University of Texas at Arlington to study the embankment located on US 67 over SH 174 in Johnson County, Cleburne, Texas. The embankment was reconstructed, replacing the top of existing fill soil with lightweight EPS 22 geofoam blocks to reduce …

Response Of Unsaturated Silty Sand Over A Wider Range Of Suction States Using A Novel Double-Walled Triaxial Testing System, Ujwalkumar Dashrath Patil

Civil Engineering Dissertations - Archive

In recent decades, the state-of-the-art of our understanding of unsaturated soil performance has been considerably enhanced by incorporating novel and advanced features to the conventional testing devices such as direct shear device, ring shear device, triaxial device and true triaxial device. The novel suction-controlled triaxial system used in this research is fully automated and has enhanced features such as volume change device and double-walled cell to monitor the volume change accurately during all the stages of unsaturated triaxial test. Despite the sophistication, such devices can help in testing mechanical behavior of unsaturated soils only up to matric suction (s) value …

Numerical Modeling Of Ground Movements Associated With Trenchless Box Jacking Technique, Babak Haji Mohammad Hasan Mamaqani

Civil Engineering Dissertations - Archive

The Trenchless Technology (TT) is defined as a family of methods used to install, renew, replace or renovate new pipe/box or existing pipe/box underground with little or no surface disruption. TT is divided into two main categories including Trenchless Construction Methods (TCMs) and Trenchless Renewal Methods (TRMs). TCMs are used to install new utilities and pipes underground while TRMs are used to renew, renovate and replace an existing utility or pipe. Box jacking (BJ) is a TCM used to install rectangular box culverts under existing facilities such as highways and railroads. In this method, box culverts are pushed through the …

Suspended Sediment And Nutrient Behaviour On The River Bandon, Ireland, James Hickey

Theses

Suspended sediment is a key contributor to contaminant transfer within river systems. The relationship between the transport of suspended sediment and nutrients influences the status of water quality and sustainability of aquatic habitats. This thesis studies suspended sediment and nutrient transport on the River Bandon.

This thesis includes a literature review of suspended sediment and nutrient transport, appropriate legislation, river flow representation and flood frequency estimation.

As part of a structured field monitoring programme, manual samples have been collected periodically and tested for suspended sediment concentration (SSC), turbidity, five species of phosphorus and five species of nitrogen. Continuous in-situ turbidity …

Achieving ‘Net Zero Energy’ Performance Through Retrofitting Of Residential Buildings In Ireland., M. Alan Costello

Theses

A Net Zero Energy Building (nZEB) is a residential or commercial building that consumes net zero energy over a set period of time, usually taken as one year. In short, for every unit of energy the building consumes over a year, it must generate a unit of energy to maintain an overall net balance. This is achieved by reducing the operational energy usage to a very low level through energy efficient design, and then providing renewable generation technologies on site to cater for the remaining energy demand.

Energy use in all sectors of society is under scrutiny at present, largely …

Classification Of Irish Beaches, Johnjoe O'Sullivan

Theses

This project aims to develop a beach classification model that has been validated for use on Irish beaches. Beach classification models have been developed over the past six decades as a means of identifying the sedimentological, morphological and hydrodynamic beach features that are present on beaches. Beach classification models have been pioneered by researchers for beaches in Australia and have been subject to continuous development through the monitoring and research of beaches along the Australian coastline. Recently a similar model been developed for England and Wales based on data collected from beaches along the coastline. This report will investigate the …

A Technical And Economic Appraisal Of Insulation Retrofits, Niamh O'Brien

Theses

The main aim of this literature review is to further develop the project brief and to examine what research has previously been undertaken in the field of thermal conductivity and retrofitting insulation. The basis of this project is to determine the effect of moisture in domestic cavity walls on the effectiveness of retrofitted insulation. The research began by highlighting the reasoning behind the need for insulation within domestic dwellings within Ireland and the guiding legislation in place in relation to this. Carrying on from this, the current methods used to retrofit insulation were examined, along with the types of insulation …

A Technical And Economic Appraisal Of Insulation Retrofits, Niamh O'Brien

Theses

The main aim of this literature review is to further develop the project brief and to examine what research has previously been undertaken in the field of thermal conductivity and retrofitting insulation. The basis of this project is to determine the effect of moisture in domestic cavity walls on the effectiveness of retrofitted insulation. The research began by highlighting the reasoning behind the need for insulation within domestic dwellings within Ireland and the guiding legislation in place in relation to this. Carrying on from this, the current methods used to retrofit insulation were examined, along with the types of insulation …

Spatial And Temporal Modeling Of Radar Rainfall Uncertainties, Gabriele Villarini, Bong Chul Seo, Francesco Serinaldi, Witold F. Krajewski

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

It is widely acknowledged that radar-based estimates of rainfall are affected by uncertainties (e.g., mis-calibration, beam blockage, anomalous propagation, and ground clutter) which are both systematic and random in nature. Improving the characterization of these errors would yield better understanding and interpretations of results from studies in which these estimates are used as inputs (e.g., hydrologic modeling) or initial conditions (e.g., rainfall forecasting). Building on earlier efforts, the authors apply a data-driven multiplicative model in which the relationship between true rainfall and radar rainfall can be described in terms of the product of a systematic and random component. The systematic …

Form Pressure Generated By Fresh Concrete: A Review About Practice In Formwork Design, Tilo Proske, Kamal Khayat, Ahmed Omran, Olaf Leitzbach

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In this paper, several current industrial practices in formwork design are presented focusing on the normative calculation of the form pressure. Most of the current Standards are devoting for the design of the formwork for the normal vibrated concrete. Currently, the Standards are being updated to include provisions for the newly adapted concrete, such as the flowable concrete and self-consolidating concrete. However, the experience with these methods is still limited. The available methods for calculating the formwork pressure for the flowable concrete and SCC are based on measuring the shear strength of concrete using different concepts, such as the setting …

Use Of Innovative Techniques To Enhance The Hydraulic Disinfection Efficiency Of Drinking Water Contact Tanks, J. J. Kattnig, S. K. Venayagamoorthy

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The focus of this study was to understand the complex nature of flow dynamics within water disinfection contact tanks and to use this understanding in the development of beneficial tank modifications. Methods involved in this process included the use of computational fluid dynamics (CFD) and physical conservative tracer studies. Attempted tank alterations included the installation of baffles, inlet modification, and the use of industrial packing material. Tested modifications aimed at altering existing velocity fields to increase the hydraulic disinfection efficiency of a given system. Hydraulic efficiency was measured through the use of residence time distribution (RTD) curves and the well-known …

Quantitative Assessments Of Municipal Waste Management Systems: Using Different Indicators To Compare And Rank Programs In New York State, Krista L. Greene, David J. Tonjes

Technology & Society Faculty Publications

The primary objective of waste management technologies and policies in theUnited Statesis to reduce the harmful environmental impacts of waste, particularly those relating to energy consumption and climate change. Performance indicators are frequently used to evaluate the environmental quality of municipal waste systems, as well as to compare and rank programs relative to each other in terms of environmental performance. However, there currently is no consensus on the best indicator for performing these environmental evaluations. The purpose of this study is to examine the common performance indicators used to assess the environmental benefits of municipal waste systems to determine if …

A Review Of The Hyporheic Zone, Stream Restoration, And Means To Enhance Denitrification, Leanne Merill, David J. Tonjes

Technology & Society Faculty Publications

The hyporheic zone is the subsurface area below and adjacent to a stream where groundwater mixes with stream water, through vertical, lateral, and longitudinal flows. The hyporheic zone connects the stream to uplands and other terrestrial environments. It is a zone of distinct faunal communities, high biological diversity and ecological complexity, and is the site of chemical processing and transformations of ground- and stream waters. The hyporheic zone is important to the overall ecosystem ecology of the stream, and it can influence stream water chemistry. Flows, reactions, and biota in the hyporheic zone are heterogeneous and patchy, making it difficult …

Engineering Behavior And Characterization Of Biomass Ashes Using Geotechnical Measurement Techniques, Francisco Javier Grau Sacoto

LSU Master's Theses

Biomass, the organic material derived from plants or animals in a biological process, has rapidly become a topic of worldwide interest. The need to find new types of renewable energy sources has led to the use of natural materials as an economic, sustainable and environmental alternative. Biomass can be used to produce biofuel after a conversion process. The combustion of biomass matter –which is mainly produced in industrial plants- becomes biomass ash, which contains macronutrients and micronutrients. Currently, the recycling potential is wasted and most of the biomass ash is dumped without control or just disposed in landfills. The main …

Static, Vibration Analysis And Sensitivity Analysis Of Stepped Beams Using Singularity Functions, Peng Cheng, Carla Davila, Gene Hou

Mechanical & Aerospace Engineering Faculty Publications

A systematic approach is presented in this paper to derive the analytical deflection function of a stepped beam using singularity functions. The discontinuities considered in this development are associated with the jumps in the flexural rigidity and the applied loads. This approach is applied to static and vibration analyses of stepped beams. The same approach is later extended to perform sensitivity analysis of stepped beams. This is done by directly differentiating the analytical deflection function with respect to any beam-related design variable. The particular design variable considered here is the location of discontinuity in flexural rigidity. Example problems are presented …

Evaluation Of Truck Signal Priority At N Columbia Blvd And Martin Luther King Jr. Blvd Intersection: Vissim Micro Simulation Analysis Of Truck Signal Priority, Maisha Mahmud

Civil and Environmental Engineering Master's Project Reports

Given the importance of over growing freight transportation system worldwide, engineers and planners are faced with the challenge of improving freight service in urban area using low cost measure. Truck Signal Priority is one of the strategy that can be used to improve operational efficiency with enhance safety benefits (red light running) of freight service, without major capital investment. In light to this interest this study focus on evaluating the impacts of freight signal priority on a high truck density intersection like N Columbia Blvd and NE Martin Luther King Jr. Blvd. Using a simulation tool, VISSIM, these impacts were …

Geospatial Analysis Of Rural Motor Vehicle Traffic Crashes In Oregon, Saad Nayef Almutairi

Civil and Environmental Engineering Master's Project Reports

This research examines the spatial extent of crashes in and around city boundaries in the state of Oregon in the U.S.A. For this study, a summary of fatalities data for the year 2006 obtained from NHTSA's report (2009), crash data for the year 2012, and city boundaries were obtained from ODOT "Oregon Department of Transportation" FTP: www.odot.state.or.us. In order to differentiate between the urban and rural crashes, city boundaries were used to find the numbers of urban and rural crashes. Outside areas of this urban-rural boundary were divided into further boundaries of 2.5 miles. An intersection tool in ArcMap …

Numerical Evaluation Of The Extended Endplate Moment Connection Subjected To Cyclic Loading, Mehdi Ghassemieh, Mehdi Jalalpour, Ali Akbar Gholampour

Civil and Environmental Engineering Faculty Publications

In this paper, the seismic behaviour of extended endplate moment connection is analysed using finite element method (FEM). First, an existing test setup is modelled and analysed using ANSYS computer program. The model is validated by comparing the results from the finite element with the experimental ones. Afterwards, by changing the dimensions of members of the connection, their effect on the overall seismic performance of connection is investigated. The results show that by enlarging the column depth and stiffening the connection, the seismic performance is improved and the thickness of endplate should be chosen in a way that its moment …

Behavior Of Hybrid Frp-Concrete-Steel Double-Skin Tubes Subjected To Cyclic Axial Compression, Omar I. Abdelkarim, Mohamed A. Elgawady

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper presents the results of an experimental study that was conducted to investigate the effects of key parameters on the compressive behavior of fiber-reinforced polymer (FRP)-concrete-steel double-skin tubular columns (FSDT). Hybrid FSDT columns have been introduced as a new form of hybrid columns. They consist of an outer tube made of FRP and inner tub made of steel, with sandwiched concrete between them. This paper investigated the effect of fiber angle and the ratio of steel tube diameter to its thickness (Di/ts) on the compressive behavior of FSDT columns. Six FSDT cylinders with different (Di/ts), in addition to two …