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- Title
- Modeling of Flexible Pipe for Culvert Application under Shallow Burial Condition.
- Creator
- Limpeteeprakarn, Terdkiat, Carlsson, Leif A., Florida Atlantic University, College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
- Abstract/Description
-
Flexible thermoplastic p1pes under field and laboratory loading conditions have been examined in the present study. The flexible pipes were tested under truck loading application with shallow soil cover. The pipe-soil system response includes soil stresses around and above the buried pipes, vertical pipe crown diametral strain, and circumferential pipe wall strains. Modeling the pipe-soil system is made using plane strain and thin ring assumptions. A thin ring model using Castigliano's...
Show moreFlexible thermoplastic p1pes under field and laboratory loading conditions have been examined in the present study. The flexible pipes were tested under truck loading application with shallow soil cover. The pipe-soil system response includes soil stresses around and above the buried pipes, vertical pipe crown diametral strain, and circumferential pipe wall strains. Modeling the pipe-soil system is made using plane strain and thin ring assumptions. A thin ring model using Castigliano's theorem is developed to analyze the behavior and response of a flexible pipe under well defined loading conditions and simulate the behavior of the buried pipe under the live load application. Laboratory work was carried out to study the pipe behavior and response under two-point, three-point, and four-point loading configurations. The thin ring model predictions show good agreement with classical solutions specially valid for two-point and three-point loading configurations. Laboratory results were also in good agreement with the predictions. Laboratory results show that the maximum tensile strain for the four-point loading test occurs at inner pipe crown region. Comprehensive efforts were made to correlate the thin ring model predictions with the field test results; however, it appears that the thin ring model cannot be used to simulate the effect of the live load application. A major source of the differences between the predicted and measured values is attributed to the applied load magnitude. A further investigation was carried out to examine the applicability of the model to study the general pipe behavior. The predicted hoop pipe wall strain profile was found to be similar to that of the reported strain profile by Rogers under overall poor soil support condition. Comparison of soil stress distribution shows that the 2D prediction approach provides nonconservative results while the FE analysis agrees more favorably with the measured pressure data. Overall, FE analysis shows that a linearly elastic isotropic model for the surrounding soil and flexible pipes with a fully bonded pipe-soil interface provides a reasonable prediction for soil pressures close to the buried pipes.
Show less - Date Issued
- 2006
- PURL
- http://purl.flvc.org/fau/fd/FA00012573
- Subject Headings
- Structural analysis (Engineering), Pipe, Plastic--Dynamics--Mathematical models, Underground pipelines--Design and construction, Soil-structure interaction
- Format
- Document (PDF)
- Title
- Biogenic gas dynamics in peat soil blocks using ground penetrating radar: a comparative study in the laboratory between peat soils from the Everglades and from two northern peatlands in Minnesota and Maine.
- Creator
- Cabolova, Anastasija., Charles E. Schmidt College of Science, Department of Physics
- Abstract/Description
-
Peatlands cover a total area of approximately 3 million square kilometers and are one of the largest natural sources of atmospheric methane (CH4) and carbon dioxide (CO2). Most traditional methods used to estimate biogenic gas dynamics are invasive and provide little or no information about lateral distribution of gas. In contrast, Ground Penetrating Radar (GPR) is an emerging technique for non-invasive investigation of gas dynamics in peat soils. This thesis establishes a direct comparison...
Show morePeatlands cover a total area of approximately 3 million square kilometers and are one of the largest natural sources of atmospheric methane (CH4) and carbon dioxide (CO2). Most traditional methods used to estimate biogenic gas dynamics are invasive and provide little or no information about lateral distribution of gas. In contrast, Ground Penetrating Radar (GPR) is an emerging technique for non-invasive investigation of gas dynamics in peat soils. This thesis establishes a direct comparison between gas dynamics (i.e. build-up and release) of four different types of peat soil using GPR. Peat soil blocks were collected at peatlands with contrasting latitudes, including the Everglades, Maine and Minnesota. A unique two-antenna GPR setup was used to monitor biogenic gas buildup and ebullition events over a period of 4.5 months, constraining GPR data with surface deformation measurements and direct CH4 and CO2 concentration measurements. The effect of atmospheric pressure was also investigated. This study has implications for better understanding global gas dynamics and carbon cycling in peat soils and its role in climate change.
Show less - Date Issued
- 2010
- PURL
- http://purl.flvc.org/FAU/2974433
- Subject Headings
- Wetland ecology, Wetland ecology, Wetland ecology, Gas dynamics, Soil permeability, Ground penetrating radar, Porous materials, Fluid dynamics
- Format
- Document (PDF)
- Title
- Nitrate Use Efficiency In Tobacco Plants Constitutively Expressing A Maize Nitrate Transporter ZmNRT2.1.
- Creator
- Cruz, Jessica, Zhang, Xing-Hai, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
The NRT2 (high affinity nitrate transporter 2) family is a part of the iHATS (inducible high affinity system) that studies have shown is responsible for the influx of nitrate into the plant cell after provision of nitrate. The ZmNRT2.1 from Zea mays was constitutively expressed in Nicotiana tabacum. To assess how over-expression of this foreign NRT2.1 affects nitrate influx by plants, nitrate content in leaf and root tissue, gene expression, and vegetal growth were analyzed in media with...
Show moreThe NRT2 (high affinity nitrate transporter 2) family is a part of the iHATS (inducible high affinity system) that studies have shown is responsible for the influx of nitrate into the plant cell after provision of nitrate. The ZmNRT2.1 from Zea mays was constitutively expressed in Nicotiana tabacum. To assess how over-expression of this foreign NRT2.1 affects nitrate influx by plants, nitrate content in leaf and root tissue, gene expression, and vegetal growth were analyzed in media with deficient or high nitrate concentrations (0.1, 1, or 10 mM). Compared to wild type plants: the transgenic lines had a significantly larger fresh weight in all nitrate conditions; primary root length was significantly longer in the 0.1 and 1 mM nitrate conditions; both the fresh weight and the primary root length were significantly higher when 50 mM NaCl was applied as a stress factor to medias containing 0.1 and 10 mM nitrate.
Show less - Date Issued
- 2015
- PURL
- http://purl.flvc.org/fau/fd/FA00004492, http://purl.flvc.org/fau/fd/FA00004492
- Subject Headings
- Nitrogen--Fixation., Nitrogen-fixing plants--Metabolism., Crops and nitrogen., Field crops--Genetic engineering., Plants--Effect of nitrogen on., Soil microbiology.
- Format
- Document (PDF)
- Title
- Analysis of Backgroundwater Chemistry and Local Hydrologic Conditions ofPondhawk Natural Area Pre-Wetland Construction.
- Creator
- Carlson, Eric Sven, Root, Tara L., Florida Atlantic University
- Abstract/Description
-
This thesis evaluates the water chemistry and hydrology of an urban environmental preserve in advance of wetland construction. Pondhawk Natural Area (PNA) is located in densely populated Palm Beach County, Florida and was acquired through the County's Environmentally Sensitive Lands Acquisition Program as a protected natural area. In an effort to restore the natural area to pre-development conditions Palm Beach County will construct a wetland in the area where hydric conditions persisted...
Show moreThis thesis evaluates the water chemistry and hydrology of an urban environmental preserve in advance of wetland construction. Pondhawk Natural Area (PNA) is located in densely populated Palm Beach County, Florida and was acquired through the County's Environmentally Sensitive Lands Acquisition Program as a protected natural area. In an effort to restore the natural area to pre-development conditions Palm Beach County will construct a wetland in the area where hydric conditions persisted prior to the extensive canal construction that lowered groundwater levels. Results of this study wi II provide initial characterization of hydrology and water quality of PNA before wetland construction and lay the groundwork for future monitoring and improvements.
Show less - Date Issued
- 2008
- PURL
- http://purl.flvc.org/fau/fd/FA00000730
- Subject Headings
- Soil chemistry--Florida--Palm Beach County, Water chemistry--Florida--Palm Beach County, Wetland hydrology--Florida--Palm Beach County, Groundwater flow--Florida--Palm Beach County
- Format
- Document (PDF)
- Title
- The fate of copper in flooded south Florida agricultural soils and its toxicological effects on the Florida apple snail, Pomacea paludosa.
- Creator
- Rogevich, Emily Catherine, Florida Atlantic University, Brooks, W. Randy, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Agricultural sites have been acquired under the Comprehensive Everglades Restoration Plan (CERP) for the creation of water storage areas. Copper desorption and toxicity to the Florida apple snail (Pomacea paludosa) were investigated using soils from these sites. Copper concentrations in II soils ranged from 5 to 234 mg/kg Cu dw, and when flooded, resulted in overlying water Cu concentrations from 9 to 308 11g/L Cu. Juvenile apple snails exposed to three flooded soils had high mortality and...
Show moreAgricultural sites have been acquired under the Comprehensive Everglades Restoration Plan (CERP) for the creation of water storage areas. Copper desorption and toxicity to the Florida apple snail (Pomacea paludosa) were investigated using soils from these sites. Copper concentrations in II soils ranged from 5 to 234 mg/kg Cu dw, and when flooded, resulted in overlying water Cu concentrations from 9 to 308 11g/L Cu. Juvenile apple snails exposed to three flooded soils had high mortality and decreased growth within 9 to 16 days in two ofthe three soils examined. To assess Cu toxicity to the apple snail at various life stages and water quality parameters, 96 hour acute toxicity studies were conducted. Copper was more toxic to juvenile than adult apple snails. Copper toxicity increased as pH decreased and decreased as DOC increased. Hardness had no effect on Cu toxicity to the apple snail. Copper toxicity was a function of organism age, DOC and pH. Copper accumulation by juvenile and adult apple snails was determined for multiple exposure pathways. For 28 days, juvenile snails were exposed to aqueous Cu and adult snails were exposed to Cu contaminated soil, water and food. Whole body Cu in juvenile snails increased with time. The mean Cu bioconcentration factor (BCF) for juvenile snails was 1493. For adult snails, the dietary exposure pathway resulted in the highest bioaccumulation factor (BAF). Most Cu accumulated in soft tissue. During a chronic aqueous exposure, apple snails exposed to 8-16 flg /L Cu for 9 months had high Cu accumulation and significantly reduced clutch production (8-16 flg /L) and egg hatching (16 flg/L ). Chronic Cu exposure initially decreased growth in juvenile snails, but growth rebounded by adulthood and snails appeared to acclimate to chronic Cu exposure. When apple snails with high tissue Cu were fed to redear sunfish (Lepomis microlophus) Cu transfer was minimal, suggesting that the risk of trophic transfer (bioaccumulation) of Cu from the snail to redear sunfish is low and that biomagnification is unlikely. It is uncertain if other apple snail predators would be at risk for dietary Cu transfer.
Show less - Date Issued
- 2008
- PURL
- http://purl.flvc.org/fau/fd/FA00000875
- Subject Headings
- Soil pollution--Florida, Florida applesnail--Habitat, Florida applesnail--Effect of heavy metals on, Copper--Toxicology, Ecosystem management--Florida
- Format
- Document (PDF)
- Title
- Inlet-Adjacent Shoreline Behavior at Three Stabilized Inlets in Palm Beach County, FL (USA).
- Creator
- Vandamas, Edward A, Briggs, Tiffany Roberts, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Geosciences
- Abstract/Description
-
Shorelines are a primary source of attraction for the nearly two million tourists who visit Palm Beach County annually. Many of Palm Beach County beaches are located on barrier islands, separated by a series of inlets which serve as access points to the Intracoastal Waterway. However, inlets are often cited as a source of erosion, through interruption of littoral drift and interaction with nearshore hydrodynamics (e.g., causing wave diffraction or refraction). In an effort to mitigate...
Show moreShorelines are a primary source of attraction for the nearly two million tourists who visit Palm Beach County annually. Many of Palm Beach County beaches are located on barrier islands, separated by a series of inlets which serve as access points to the Intracoastal Waterway. However, inlets are often cited as a source of erosion, through interruption of littoral drift and interaction with nearshore hydrodynamics (e.g., causing wave diffraction or refraction). In an effort to mitigate potential negative impacts of the economically important tidal inlets, Palm Beach County has installed a sand transfer plant (STP) at two inlet locations, the Lake Worth Inlet and the South Lake Worth Inlet. Through analysis of annual aerial photography and beach profile surveys taken between 2000 and 2009, this study will determine what effect, if any, these sand transfer plants are having on the inlet-adjacent shorelines north and south of the two inlets with STP, as well as an inlet without an STP (Boca Inlet). This study hopes to increase the understanding of shoreline dynamics in Palm Beach County, which could recognize important alongshore patterns, such as the occurrence of erosional hot spots, to assist in future mitigation efforts.
Show less - Date Issued
- 2015
- PURL
- http://purl.flvc.org/fau/fd/FA00004554, http://purl.flvc.org/fau/fd/FA00004554
- Subject Headings
- Beach erosion -- Florida -- Lake Worth Inlet -- Prevention, Beach erosion -- Florida -- South Lake Worth Inlet -- Prevention, Coastal changes -- Florida -- Palm Beach County, Coastal zone management -- Florida -- Palm Beach County, Geodynamics, Soil conservation -- Florida -- Lake Worth Inlet, Soil conservation -- Florida -- South Lake Worth Inlet, Sustainable development
- Format
- Document (PDF)
- Title
- Address to the people of Massachusetts.
- Creator
- Curtis, Benjamin Robbins 1809-1874, Whig Party (Mass.)
- Abstract/Description
-
On the coalition of 1851 between the Free Soilers and the Democrats of Massachusetts, and the consequent election of Charles Sumner as U.S. Senator for Massachusetts. Notes: Cover title. Half-title serves as title page. Caption title: To the people of Massachusetts. Attributed to B.R. Curtis. Cf. NUC pre-1956 imprints. Signed by William Aspinwall and 166 other Whig members of the Senate and the House of Representatives of Massachusetts. FAU Libraries' copy in original paper wrappers with...
Show moreOn the coalition of 1851 between the Free Soilers and the Democrats of Massachusetts, and the consequent election of Charles Sumner as U.S. Senator for Massachusetts. Notes: Cover title. Half-title serves as title page. Caption title: To the people of Massachusetts. Attributed to B.R. Curtis. Cf. NUC pre-1956 imprints. Signed by William Aspinwall and 166 other Whig members of the Senate and the House of Representatives of Massachusetts. FAU Libraries' copy in original paper wrappers with title on front within ornamental border; side stitched with brown cord.
Show less - PURL
- http://purl.flvc.org/fau/fd/fauwsb15f25
- Subject Headings
- Massachusetts -- Politics and government -- 1775-1865, Boutwell, George S. -- (George Sewall) -- 1818-1905, Democratic Party (Mass.), Free Soil Party (Mass.), Speeches, addresses, etc., American -- 19th century, Sumner, Charles -- 1811-1874
- Format
- E-book
- Title
- Three-dimensional geomodeling to identify spatial relations between lithostratigraphy and porosity in the karst carbonate biscayne aquifer, southeastern Florida.
- Creator
- Westcott, Richard, Root, Tara L., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Geosciences
- Abstract/Description
-
In southeastern Florida, the majority of drinking water comes from the Biscayne aquifer. This aquifer is comprised of heterogeneous limestones, sandstones, sand, shell and clayey sand with zones of very high permeability. Visualizing the spatial variations in lithology, porosity and permeability of heterogeneous aquifers, like the Biscayne, can be difficult using traditional methods of investigation. Using the Roxar IRAP RMS software multi-layered 3D conceptual geomodels of the lithology,...
Show moreIn southeastern Florida, the majority of drinking water comes from the Biscayne aquifer. This aquifer is comprised of heterogeneous limestones, sandstones, sand, shell and clayey sand with zones of very high permeability. Visualizing the spatial variations in lithology, porosity and permeability of heterogeneous aquifers, like the Biscayne, can be difficult using traditional methods of investigation. Using the Roxar IRAP RMS software multi-layered 3D conceptual geomodels of the lithology, cyclostratigraphy and porosity were created in a portion of the Biscayne aquifer. The models were built using published data from borehole geophysical measurements, core samples, and thin sections. Spatial relations between lithology, cyclostratigraphy, porosity, and preferential flow zones were compared and contrasted to better understand how these geologic features were inter-related. The models show local areas of differing porosity within and cross-cutting different cycles and lithologies. Porosity in the Biscayne aquifer study area follows a hierarchy attributed to lithofacies with a pattern of increasing porosity for the high frequency cycles. This modeling improves understanding of the distribution and interconnectedness of preferential flow zones, and is thus an invaluable tool for future studies of groundwater flow and groundwater contamination in the Biscayne aquifer.
Show less - Date Issued
- 2014
- PURL
- http://purl.flvc.org/fau/fd/FA00004337, http://purl.flvc.org/fau/fd/FA00004337
- Subject Headings
- Biscayne Aquifer (Fla.), Geophysics -- Florida -- Miami Dade County, Groundwater flow -- Florida -- Miami Dade County -- Mathematical models, Hydrology, Karst -- Florida -- Miami Dade County, Porosity, Sedimentary basins -- Florida -- Biscayne Aquifer, Sedimentology -- Statistical methods, Soil permeability
- Format
- Document (PDF)
- Title
- The great fraud upon the public credulity in the organization of the Republican party upon the ruins of the "Whig party," an address to the old-line Whigs of the Union.
- Creator
- National Whig
- Abstract/Description
-
Decries the newly formed Republican Party as a destructive force. Caption title: Duties of the Whigs of the American Union Notes: Signed: National Whig. FAU copy imperfect: pages loose, all edges trimmed (to 21 cm).
- PURL
- http://purl.flvc.org/fau/fd/fauwsb18f8
- Subject Headings
- Antislavery movements -- United States, Campaign literature, 1856 -- Democratic, Campaign literature, 1856 -- Whig Party (U.S.), Free Soil Party (U.S.), Fugitive slaves -- United States, Libel and slander -- United States, Political parties -- United States -- Platforms, Politics and government, Press and politics -- United States, Republican Party (U.S. : 1854- )
- Format
- E-book
