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Full-Text Articles in Civil and Environmental Engineering

Interface Friction Parameters For The Mathematical Modeling Of Shell Structures With Infill, Alexander T. Bekker, Nikita Ya. Tsimbelman, Tatiana I. Chernova, Vadim D. Bruss, Ömer Bilgin Jun 2015

Interface Friction Parameters For The Mathematical Modeling Of Shell Structures With Infill, Alexander T. Bekker, Nikita Ya. Tsimbelman, Tatiana I. Chernova, Vadim D. Bruss, Ömer Bilgin

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

Thin metal or reinforced concrete shells with granular infill structures are considered in this article. These structures are massive and they are used as support for the construction of berthing quays, piers, artificial islands, shore protection, and other structures of coastal infrastructure. It is more convenient to use the thin shell structures during the development of the Arctic shelf, because it is possible to install them from the ice side. In addition, it is possible to enhance the technology and install thin shells with infill on deeper solid foundation layers. A mathematical model for the stresses on a compressible foundation …


Feasibility Study: The Evaluation Of Polymer Coatings To Prevent Weathering Of Weak Rocks, Lauren Distler May 2015

Feasibility Study: The Evaluation Of Polymer Coatings To Prevent Weathering Of Weak Rocks, Lauren Distler

Senior Honors Projects, 2010-2019

The weathering and erosion of weak rocks along roadways can cause dangerous and potentially fatal rockfalls.   Various slope stabilization methods exist, but each presents a set of challenges and trade-offs.   The focus of the project is to understand the feasibility of utilizing of a polymerbased slope stabilization technique. Rock samples were collected along US Route 33 in Virginia and West Virginia, and preliminary tests were conducted to evaluate the absorption of water (% mass) and durability. The study evaluates three polymer options in regard to the following criteria: adhesion to rock, layer thickness, semi-permeability, insolubility, and non-toxicity. The polymer selection …


Probabilistic Precipitation Estimation With A Satellite Product, Nir Y. Krakauer, Soni M. Pradhanang, Jeeban Panthi, Tarendra Lakhankar, Ajay K. Jha Apr 2015

Probabilistic Precipitation Estimation With A Satellite Product, Nir Y. Krakauer, Soni M. Pradhanang, Jeeban Panthi, Tarendra Lakhankar, Ajay K. Jha

Publications and Research

Satellite-based precipitation products have been shown to represent precipitation well over Nepal at monthly resolution, compared to ground-based stations. Here, we extend our analysis to the daily and subdaily timescales, which are relevant for mapping the hazards caused by storms as well as drought. We compared the Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA) 3B42RT product with individual stations and with the gridded APHRODITE product to evaluate its ability to retrieve different precipitation intensities. We find that 3B42RT, which is freely available in near real time, has reasonable correspondence with ground-based precipitation products on a daily timescale; rank …


On The Influence Of Ionic Strength On Radium And Strontium Sorption To Sandy Loam Soils, Brian A. Powell, Todd Miller, Daniel I. Kaplan Apr 2015

On The Influence Of Ionic Strength On Radium And Strontium Sorption To Sandy Loam Soils, Brian A. Powell, Todd Miller, Daniel I. Kaplan

Journal of the South Carolina Academy of Science

Models which can estimate environmental transport of radioactive contaminants in natural and engineered systems are required to 1) deploy effective remediation strategies for contaminated sites, 2) design waste repositories for future waste streams, and 3) ensure protection of human and environmental health in all cases. These models require accurate transport parameters in order to correctly predict how these contaminants will move in the subsurface. This work aimed to determine more accurately the distribution coefficients for radium and strontium sorption to Savannah River Site (SRS) soils. Radium and strontium sorption to the soils was found to be highly dependent upon ionic …


Downward Model Development Of The Soil Moisture Accounting Loss Method In Hec-Hms: Revelations Concerning The Soil Profile, Jessica Holberg Apr 2015

Downward Model Development Of The Soil Moisture Accounting Loss Method In Hec-Hms: Revelations Concerning The Soil Profile, Jessica Holberg

Open Access Theses

Despite the fact that the soil profile is known to impact streamflow, most Curve Number (CN)-based models ignore subsurface processes. This study explores the influence of soil storage on peak flows. Two watersheds in flat, humid west-central Indiana were modeled using both the Natural Resources Conservation Service (NRCS) Curve Number and four versions of the Soil Moisture Accounting (SMA) loss methods in the United States Army Core of Engineers-developed (USACE) Hydrologic Engineering Center Hydrologic Modeling System (HEC-HMS). One watershed encompasses the Wabash and Tippecanoe Rivers' confluence; the other contains an ephemeral stream, Plum Creek. The CN-based model was developed using …


Nebraska’S Natural Resources Districts: An Assessment Of A Large-Scale Locally Controlled Water Governance Framework, Ann Bleed, Christina Hoffman Babbitt Mar 2015

Nebraska’S Natural Resources Districts: An Assessment Of A Large-Scale Locally Controlled Water Governance Framework, Ann Bleed, Christina Hoffman Babbitt

Daugherty Water for Food Global Institute: Faculty Publications

In 1972 the State of Nebraska created the Natural Resources Districts (NRDs) to consolidate a multitude of single-purpose local natural resource districts into a more comprehensive, holistic, and efficient natural resources governance system. While consolidation and efficiency was important, so was the concept of maintaining local control. Thus, Nebraska rejected the governance framework of a single top-down state agency, preferring to create NRDs that are each governed by a locally elected board. The locally elected governing boards of the NRDs were given broad authorities over many of the state’s natural resources, including groundwater. Such a governance structure was, and to …


Lightening Strikes Twice For Dit Geomatics, Audrey Martin Mar 2015

Lightening Strikes Twice For Dit Geomatics, Audrey Martin

Articles

The Technological University Dublin (DIT) is rapidly becoming known as an international centre for excellence for all things geospatial. In September 2014, Kevin O'Mahony, a final-year BSc Geomatics student, won the international Trimble Geospatial Student Competition. Kevin is the second consecutive DIT student to win this prestigious award, following on from the success of David Hyland (BSc Geomatics) in 2012. Both students submitted their papers under the supervision of Dr Audrey Martin FSCSI FRICS, Chair of the recently accredited (by SCSI) DIT MSc in Geospatial Engineering. The worldwide student competition is held every two years and is open to all …


Sustainability, Efficiency And Equitability Of Water Consumption And Pollution In Latin America And The Caribbean, Mesfin Mekonnen, Markus Pahlow, Maite M. Aldaya, Erika Zarate Feb 2015

Sustainability, Efficiency And Equitability Of Water Consumption And Pollution In Latin America And The Caribbean, Mesfin Mekonnen, Markus Pahlow, Maite M. Aldaya, Erika Zarate

Daugherty Water for Food Global Institute: Faculty Publications

This paper assesses the sustainability, efficiency and equity of water use in Latin America and the Caribbean (LAC) by means of a geographic Water Footprint Assessment (WFA). It aims to provide understanding of water use from both a production and consumption point of view. The study identifies priority basins and areas from the perspectives of blue water scarcity, water pollution and deforestation. Wheat, fodder crops and sugarcane are identified as priority products related to blue water scarcity. The domestic sector is the priority sector regarding water pollution from nitrogen. Soybean and pasture are priority products related to deforestation. We estimate …


Nephrotoxic Contaminants In Drinking Water And Urine, And Chronic Kidney Disease In Rural Sri Lanka, Tewodros Rango, Marc Jeuland, Herath Manthrithilake, Peter G. Mccornick Jan 2015

Nephrotoxic Contaminants In Drinking Water And Urine, And Chronic Kidney Disease In Rural Sri Lanka, Tewodros Rango, Marc Jeuland, Herath Manthrithilake, Peter G. Mccornick

Daugherty Water for Food Global Institute: Faculty Publications

Chronic kidney disease of unknown (“u”) cause (CKDu) is a growing public health concern in Sri Lanka. Prior research has hypothesized a link with drinking water quality, but rigorous studies are lacking. This study assesses the relationship between nephrotoxic elements (namely arsenic (As), cadmium (Cd), lead (Pb), and uranium (U)) in drinking water, and urine samples collected from individuals with and/or without CKDu in endemic areas, and from individuals without CKDu in nonendemic areas. All water samples—from a variety of source types (i.e., shallow and deep wells, springs, piped, and surface water)—contained extremely low concentrations of nephrotoxic elements, and all …


Demonstration Of A Daily High-Resolution (375-M) Alexi Evapotranspiration Product For The Nena Region, Christopher Hain, Martha C. Anderson, Mitch Schull, Christopher M.U. Neale Jan 2015

Demonstration Of A Daily High-Resolution (375-M) Alexi Evapotranspiration Product For The Nena Region, Christopher Hain, Martha C. Anderson, Mitch Schull, Christopher M.U. Neale

Daugherty Water for Food Global Institute: Faculty Publications

While the current constellation of geostationary sensors provides near-global coverage (60N to 60S) – it requires merging data from 7 satellites [resolving time differences; view angles; atmospheric correction]. Polar orbiting sensors such as MODIS and VIIRS provide daily global coverage of LST at higher resolutions than GEO sensors but at only two times per day.


Assessment Of Village Chicken Production Systems In Kambata Tambaro And Wolaita Zones, Snnpr, Ethiopia, Aman Getiso, Fitsum Tessema, Mesfin Mekonnen, Addisu Jimma, Bereket Zeleke Jan 2015

Assessment Of Village Chicken Production Systems In Kambata Tambaro And Wolaita Zones, Snnpr, Ethiopia, Aman Getiso, Fitsum Tessema, Mesfin Mekonnen, Addisu Jimma, Bereket Zeleke

Daugherty Water for Food Global Institute: Faculty Publications

The study was conducted in four woredas (Damot Gale,Of a, Angacha and Hadero Tunto) the first two of them found in Wolaita zone and two of them in Kambata Tambaro Zone of SNNPR, Ethiopia respectively. A cross-sectional survey was conducted in the study areas to assess village chicken production systems, productive and reproductive performance of village chicken and identifying constraints to village chicken production. Stratified random sampling technique was used to select 240 farming households and administer a pre-tested and structured questionnaire. The results showed that the mean age of interviewed farmers was 37.8±9.3 years; average family size & chicken …


Yield Gap Analysis Of Field Crops: Methods And Case Studies, V. O. Sadras, Kenneth Cassman, Patricio Grassini, W. G.M. Bastiaanssen, A. G. Laborte, A. E. Milne, G. Sileshi, P. Steduto Jan 2015

Yield Gap Analysis Of Field Crops: Methods And Case Studies, V. O. Sadras, Kenneth Cassman, Patricio Grassini, W. G.M. Bastiaanssen, A. G. Laborte, A. E. Milne, G. Sileshi, P. Steduto

Daugherty Water for Food Global Institute: Faculty Publications

The challenges of global agriculture have been analysed exhaustively and the need has been established for sustainable improvement in agricultural production aimed at food security in a context of increasing pressure on natural resources. Whereas the importance of R&D investment in agriculture is increasingly recognised, better allocation of limited funding is essential to improve food production. In this context, the common and often large gap between actual and attainable yield is a critical target. Realistic solutions are required to close yield gaps in both small and large scale cropping systems worldwide; to make progress in this direction, we need (1) …


Geotechnical Statistical Evaluation Of Lahore Site Data And Deep Excavation Design, Aiza Malik Jan 2015

Geotechnical Statistical Evaluation Of Lahore Site Data And Deep Excavation Design, Aiza Malik

Civil and Environmental Engineering Master's Project Reports

Geotechnical characterization for foundation design is critical during preliminary planning, designing and feasibility studies of various engineering projects. In this research, an effort has been made to develop a geotechnical database for the city of Lahore, Pakistan. This database would aid geologists and engineers involved in the geotechnical design and planning of engineering projects in Lahore. The project area has been divided into zones geographically. Soil profiles have been developed for all zones, which provide ranges of soil properties and SPT-N values at regular intervals. Furthermore, the research also focuses on deep excavations in urban areas of Lahore, Pakistan and …


Commercialization Of A Small, Lightweight, Low-Cost Seismic Borehole Receiver, Rachel Adams Jan 2015

Commercialization Of A Small, Lightweight, Low-Cost Seismic Borehole Receiver, Rachel Adams

Theses and Dissertations--Civil Engineering

Herein, conceptualization of a recently patented seismic borehole receiver and its components is developed for commercialization. The device is significantly cheaper, lighter, and smaller than existing technologies on the market. Additionally, it has the potential to achieve better seismic readings than its competitors via patented sensor-to-borehole coupling mechanism. It is the hope that the commercialization of this device will not only provide a more affordable alternative to engineers and geophysicists in the existing market, but the significant cost difference may open new seismic measurement opportunities in the developing world. Its compact size and light weight will increase mobility, allowing investigators …


Detection, Occurrence And Fate Of Emerging Contaminants In Agricultural Environments, Daniel D. Snow, David A. Cassada, Shannon L. Bartelt-Hunt, Xu Li, Matteo D'Alessio, Rachel Levine, Yun Zhang, J. Brett Sallach Jan 2015

Detection, Occurrence And Fate Of Emerging Contaminants In Agricultural Environments, Daniel D. Snow, David A. Cassada, Shannon L. Bartelt-Hunt, Xu Li, Matteo D'Alessio, Rachel Levine, Yun Zhang, J. Brett Sallach

Nebraska Water Center: Faculty Publications

A total of 43 papers published in 2014 were reviewed ranging from detailed descriptions of analytical methods, to fate and occurrence studies, to measuring and predicting biological effects for a wide variety of emerging contaminants likely to occur in agricultural environments. New methods and studies on veterinary pharmaceuticals, natural and synthetics steroids, and antibiotic resistance genes in agricultural environments continue to expand our knowledge base on the occurrence and potential impacts of these compounds. This review is divided into the following sections: Introduction, Analytical Methods, Occurrence and Fate, Antibiotic Resistance Genes, and Risk Assessment.


Salt And Mineral Recovery From High Salinity Waters, Osvaldo Alejandro Broesicke Jan 2015

Salt And Mineral Recovery From High Salinity Waters, Osvaldo Alejandro Broesicke

Open Access Theses & Dissertations

Natural salt springs in the Salt Fork Basin in Crosby County, Texas, result in the natural salt pollution of the Brazos River, rendering it unusable for most potable purposes. Previous research indicates that by intercepting the source of the pollution, water quality of the Brazos River can be greatly improved. This paper investigates and assesses two strategies for salt and mineral recovery using natural brine collected from the Salt Fork Basin, the first of which is presented in a separate work.

The research described in this paper evaluates the potential of a desulfation, soda-caustic softening, acidification/decarbonation, and evaporation process to …


Vapor Flow Resistance Of Dry Soil Layer To Soil Water Evaporation In Arid Environment: An Overview, Xixi Wang Jan 2015

Vapor Flow Resistance Of Dry Soil Layer To Soil Water Evaporation In Arid Environment: An Overview, Xixi Wang

Civil & Environmental Engineering Faculty Publications

Evaporation from bare sandy soils is the core component of the hydrologic cycle in arid environments, where vertical water movement dominates. Although extensive measurement and modeling studies have been conducted and reported in existing literature, the physics of dry soil and its function in evaporation is still a challenging topic with significant remaining issues. Thus, an overview of the previous findings will be very beneficial for identifying further research needs that aim to advance our understanding of the vapor flow resistance (VFR) effect on soil water evaporation as influenced by characteristics of the dry soil layer (DSL) and evaporation zone …


Evaluating Methods Of Field-Based 3d Visualization And Their Application To Mapping Metamorphic Terranes: An Example From The Panamint Mountains, California, Jade Ashley Brush Jan 2015

Evaluating Methods Of Field-Based 3d Visualization And Their Application To Mapping Metamorphic Terranes: An Example From The Panamint Mountains, California, Jade Ashley Brush

Open Access Theses & Dissertations

Field geology has traditionally relied on 2D, paper-based workflows, but digital mapping techniques are rapidly replacing these outdated methods because they allow for more efficient and accurate mapping. This research applies digital mapping techniques and two terrestrially-based 3D visualization technologies, photogrammetry and Light Detection and Ranging (LiDAR), to the study of metamorphic terranes in the Panamint Mountains, California. This study reports on the spatial accuracy of TINs (triangulated irregular networks) generated from both photogrammetry and ground-based LiDAR using a terrestrial laser scanner (TLS) and discusses how spatial accuracy can be increased. Two levels of comparison were used to test spatial …


The Simulation & Evaluation Of Surge Hazard Using A Response Surface Method In The New York Bight, Michael H. Bredesen Jan 2015

The Simulation & Evaluation Of Surge Hazard Using A Response Surface Method In The New York Bight, Michael H. Bredesen

UNF Graduate Theses and Dissertations

Atmospheric features, such as tropical cyclones, act as a driving mechanism for many of the major hazards affecting coastal areas around the world. Accurate and efficient quantification of tropical cyclone surge hazard is essential to the development of resilient coastal communities, particularly given continued sea level trend concerns. Recent major tropical cyclones that have impacted the northeastern portion of the United States have resulted in devastating flooding in New York City, the most densely populated city in the US. As a part of national effort to re-evaluate coastal inundation hazards, the Federal Emergency Management Agency used the Joint Probability Method …


Spatio-Temporal Patterns Of Water Table And Vegetation Status Of A Deserted Area, Limin Duan, Tingxi Liu, Xixi Wang, Yanyun Luo Jan 2015

Spatio-Temporal Patterns Of Water Table And Vegetation Status Of A Deserted Area, Limin Duan, Tingxi Liu, Xixi Wang, Yanyun Luo

Civil & Environmental Engineering Faculty Publications

Understanding groundwater-vegetation interactions is crucial for sustaining fragile environments of desert areas such as the Horqin Sandy Land (HSL) in northern China. This study examined spatio-temporal variations in the water table and the associated vegetation status of a 9.71 km2 area that contains meadowland, sandy dunes, and intermediate transitional zones. The depth of the water table and hydrometeorologic parameters were monitored and Landsat Thematic Mapper (TM) and Moderate Resolution Imaging Spectroradiometer (MODIS) data were utilized to assess the vegetation cover. Spatio-temporal variations over the six-year study period were examined and descriptive groundwater-vegetation associations developed by overlaying a water table …


Applications Of Remote Sensing To The Study Of Estuarine Physics: Suspended Sediment Dynamics In The Columbia River Estuary, Austin Scott Hudson Dec 2014

Applications Of Remote Sensing To The Study Of Estuarine Physics: Suspended Sediment Dynamics In The Columbia River Estuary, Austin Scott Hudson

Dissertations and Theses

Estuarine circulation and its associated transport processes drive the environmental integrity of many near-shore habitats (the coastal ocean, rivers, estuaries and emergent wetlands). A thorough understanding and consideration of this circulation is, therefore, vital in the proper management of these habitats. The aim of this study is to bring together theory and new satellite observations in the Columbia River Estuary to increase our understanding of estuarine circulation and transport. Surface reflectance measurements gathered by the Moderate Imaging Spectroradiometer (MODIS) are first compared to in situ observations to develop an empirical model for remotely derived surface turbidity. Results indicate that MODIS …


Development Of A Hydrologic Model For An Urban Headwater Stream: The Influence Of Pervious Surface Properties On Runoff Dynamics, Dawn A. Farver Dec 2014

Development Of A Hydrologic Model For An Urban Headwater Stream: The Influence Of Pervious Surface Properties On Runoff Dynamics, Dawn A. Farver

Graduate Theses and Dissertations

A hydrologic model was developed for the Mullins Creek (MC) catchment located on the University of Arkansas campus in Fayetteville, Arkansas. The MC catchment is a small, dynamic urban stream system with a range of land use/land cover (LULC), an extensive and well-developed stormwater drainage network, and extensive urbanization (over 90% developed, and almost 50% impervious surface area (ISA)). Selected datasets provided information on the stormwater drainage network, the physical attributes of the catchment and receiving waterway (i.e. drainage area, slope, etc.), infiltration potential of soil map units, LULC, and percent ISA. These datasets were analyzed to provide input parameters …


Identification Of Groundwater Sources For Municipal Wells Using Geochemical Data On The Platte Alluvial Aquifer And Underlying Limestone At The Lincoln Water Well Field Near Ashland Nebraska, Juanita Cruz Torres Dec 2014

Identification Of Groundwater Sources For Municipal Wells Using Geochemical Data On The Platte Alluvial Aquifer And Underlying Limestone At The Lincoln Water Well Field Near Ashland Nebraska, Juanita Cruz Torres

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Alluvial aquifer systems where pumping of municipal wells induces recharge from the adjacent river are the primary source of water for many cities. The city of Lincoln, NE has a primary water source in an alluvial aquifer adjacent to the Platte River. The Lincoln Water System manages the stream/aquifer system by using integrated models for a better understanding during periods of high stress such as a drought. The integrated models set the limestone aquifer as an impermeable boundary to understand the alluvial aquifer system without having a secondary water source. The limestone aquifer is permeable and the purpose of this …


Gis Framework For Spatiotemporal Mapping Of Urban Flooding And Analyze Watershed Hydrological Response To Land Cover Change, Sayed Joinal Hossain Abedin Dec 2014

Gis Framework For Spatiotemporal Mapping Of Urban Flooding And Analyze Watershed Hydrological Response To Land Cover Change, Sayed Joinal Hossain Abedin

UNLV Theses, Dissertations, Professional Papers, and Capstones

Urban flooding is a manmade disaster, and a recurrent problem in cities around the globe. Increased surface imperviousness due to urbanization along with inadequate drainage infrastructure system are the chief culprits for urban flooding. Flooding in an urban area brings about severe economic, structural, and environmental damages, and can be associated with casualties too. In order to evade flooding, an efficient flood model is imperative to study current flooding, and analyze flooding behavior to urban surface characteristics.

This research aims to develop a framework using Geographic Information System (GIS) to perform modeling and mapping of flood spatiotemporal variation in urban …


Identification Of Long Term Changes And Evaluation Of The Relationships Among Streamflow Variability And Oceanic-Atmospheric Indices, Soumya Sagarika Dec 2014

Identification Of Long Term Changes And Evaluation Of The Relationships Among Streamflow Variability And Oceanic-Atmospheric Indices, Soumya Sagarika

UNLV Theses, Dissertations, Professional Papers, and Capstones

To examine the effects of climate variability on streamflow, this thesis presents a comprehensive analysis of the streamflow variability of the continental United States and its association with oceanic-atmospheric indices. First, the presence of trends with consideration of short term and long term persistence followed by shifts over the past years in the continental U.S. streamflow were analyzed by using the non-parametric tests: Mann Kendall and Pettitt. Second, the spatio-temporal relationships between seasonal streamflow variability of continental U.S. and sea surface temperatures (SST) and 500 mbar geopotential height (Z500) of the Pacific and Atlantic were established using the singular valued …


Toward Understanding The Thermodynamics And Mechanisms Of Actinide Sorption Reactions, Shanna Estes Dec 2014

Toward Understanding The Thermodynamics And Mechanisms Of Actinide Sorption Reactions, Shanna Estes

All Dissertations

The environmental fate of actinides is greatly influenced by interfacial reactions, including sorption onto solid surfaces. Because changes in the primary hydration sphere of the actinide are expected to greatly influence the thermodynamics (i.e., reaction enthalpy and entropy) of these reactions, examining actinide sorption thermodynamics may provide insight into actinide sorption mechanisms. Additionally, examining actinide sorption thermodynamics may enhance the ability to model or predict these reactions in environmental or engineered systems where variable or elevated temperatures are expected. However, few researchers have studied actinide sorption thermodynamics. Therefore, this research examined the thermodynamics of Eu(III) (a trivalent actinide analog), Th(IV), …


A New Passive Surface Water Flux Meter For Simultaneous Measurement Of Contaminant And Water Fluxes In Streams And Rivers, Stephen A. Sassman Oct 2014

A New Passive Surface Water Flux Meter For Simultaneous Measurement Of Contaminant And Water Fluxes In Streams And Rivers, Stephen A. Sassman

Open Access Dissertations

A passive surface water flux meter (PSFM) for measurement of contaminant concentration/flux in rivers and streams is described and tested. The novel PSFM design was developed for portability and ease of adaptability for a variety of contaminant classes. Although previous designs have been evaluated under constant flow conditions, the PSFM has never been used for measurement of pesticides or hormones and this is the first time that it has been tested under transient flow. Discharge through the PSFM is assessed by measuring miscible displacement of alcohol tracers from granular activated carbon (GAC). The tracer retardation factors (R) measured by miscible …


Evaluation Of Collapse Indicators For Seismically Vulnerable Reinforced Concrete Buildings, Nicholas R. Skok Oct 2014

Evaluation Of Collapse Indicators For Seismically Vulnerable Reinforced Concrete Buildings, Nicholas R. Skok

Open Access Theses

Older reinforced concrete buildings can be prone to column shear and compression failures during earthquakes because of inadequate transverse reinforcement. Cities in seismic areas still have large inventories of older and potentially deficient buildings. To analyze every building and estimate its vulnerability in detail is costly. A simple method to rank quickly older buildings according to their seismic vulnerability is needed to help engineers prioritize the use of resources for rehabilitating the most vulnerable buildings.

Four indicators of building damage or collapse were evaluated using numerical analysis and prior data from building surveys: column index (Hassan & Sozen, 1997), R …


Hydro-Climate Temporal Variations And Their Influences On Net Primary Production In A Eurasian Steppe Watershed, Xiaomin Yang Oct 2014

Hydro-Climate Temporal Variations And Their Influences On Net Primary Production In A Eurasian Steppe Watershed, Xiaomin Yang

Civil & Environmental Engineering Theses & Dissertations

Climate, which is the most important factor that influences Net Primary Productivity, has been detected changing all over the world. The confounding effects of step change invalidate the stationarity assumption of commonly used trend analysis methods such as the Mann-Kendall test technique, so previous studies have failed to explain inconsistencies between detected trends and observed large anomalies. In this research, by formulating a trend analysis approach that considers nonstationary due to step changes, trends and extreme occurrences of precipitation, temperature, and runoff in annual, seasonal, and monthly scales were analyzed in a mid-latitude Eurasian steppe watershed in northeast China, and …


Field-Obtained Soil Water Characteristic Curves And Hydraulic Conductivity Functions, Elvis Ishimwe Aug 2014

Field-Obtained Soil Water Characteristic Curves And Hydraulic Conductivity Functions, Elvis Ishimwe

Graduate Theses and Dissertations

A compacted clay liner (test pad) was constructed and instrumented with volumetric water content and soil matric potential sensors to determine soil water characteristic curves (SWCC) and hydraulic conductivity (k) functions. Specifically, the compacted clay liner was subjected to an infiltration cycle during a sealed double ring infiltrometer (SDRI) test followed by a drying cycle. After the drying cycle, Shelby tube samples were collected from the compacted clay liner and flexible wall permeability (FWP) tests were conducted on sub-samples to determine the saturated hydraulic conductivity. Moreover, two computer programs (RETC and UNSAT-H) were utilized to model the SWCCs and k-functions …