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You searched for subject:(surface river ice). Showing records 1 – 3 of 3 total matches.

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University of Alberta

1. Ghobrial, Tadros I.R. Characterization of Suspended Frazil and Surface Ice in Rivers Using Sonars.

Degree: PhD, Department of Civil and Environmental Engineering, 2012, University of Alberta

This research describes laboratory and field experiments aiming at developing techniques for obtaining quantitative measurements of suspended frazil ice and surface ice characteristics in rivers using sonars. A series of laboratory experiments were conducted to correlate the sonar backscatter signal from a high (546 kHz) and low (235 kHz) frequency units with direct measurements of frazil concentration. The sonar measurements showed that the high frequency unit is more sensitive to the presence of suspended frazil particles than the low frequency unit, especially at lower concentrations. A strong correlation was found between the acoustic relative backscatter from both sonar units and the measured concentrations. This calibration was conducted over a range of frazil mass concentrations between 0.012 and 0.135 % and the majority of observed frazil particles were disk shaped, varying in diameter from 0.25 to 4.25 mm. An algorithm has been developed to measure surface ice characteristics using field data from the high and low frequency sonars, a 2 MHz current profiler, and a monitoring station, deployed on the North Saskatchewan River in the north east of Edmonton, AB, Canada, during the 2009/2010 freeze-up season. The validity and the accuracy of these measurements were tested and results are presented. Over the entire season, pans/rafts drafts ranging from 0.1 to 1.0 m and pan/raft lengths ranging from 0.6 to 8.0 m were measured. The sonar proved to be very accurate in detecting the exact surface ice conditions locally above the sonar beam. Acoustic field data gathered during suspended frazil events have been processed and analyzed to provide estimates of frazil concentration and particle sizes using laboratory regression equations and fluid disk scattering model. In total, eight frazil events were detected with the sonars during the field deployment. Preliminary linkages between the meteorological (air and water temperatures) and surface ice conditions measured at the site, and the duration and magnitude of the detected frazil events are presented. Concentrations ranging between 0.01 and 0.05% and disk radii between 0.13 and 0.21 mm have been estimated from the field data.

Subjects/Keywords: frazil ice; surface river ice; underwater sonars

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Ghobrial, T. I. R. (2012). Characterization of Suspended Frazil and Surface Ice in Rivers Using Sonars. (Doctoral Dissertation). University of Alberta. Retrieved from https://era.library.ualberta.ca/files/08612p34m

Chicago Manual of Style (16th Edition):

Ghobrial, Tadros I R. “Characterization of Suspended Frazil and Surface Ice in Rivers Using Sonars.” 2012. Doctoral Dissertation, University of Alberta. Accessed December 15, 2019. https://era.library.ualberta.ca/files/08612p34m.

MLA Handbook (7th Edition):

Ghobrial, Tadros I R. “Characterization of Suspended Frazil and Surface Ice in Rivers Using Sonars.” 2012. Web. 15 Dec 2019.

Vancouver:

Ghobrial TIR. Characterization of Suspended Frazil and Surface Ice in Rivers Using Sonars. [Internet] [Doctoral dissertation]. University of Alberta; 2012. [cited 2019 Dec 15]. Available from: https://era.library.ualberta.ca/files/08612p34m.

Council of Science Editors:

Ghobrial TIR. Characterization of Suspended Frazil and Surface Ice in Rivers Using Sonars. [Doctoral Dissertation]. University of Alberta; 2012. Available from: https://era.library.ualberta.ca/files/08612p34m


University of Florida

2. Foster, Jessica. Incremental volumetric calculation using LiDAR and GIS : A methodology for predicting flood trigger levels.

Degree: 2012, University of Florida

Ice jams occur annually along the Mohawk River in upstate New York, especially when the downstream progress of the ice is impeded by obstructions to the channel and flood plain. It is critical to know the trigger level of floods caused by ice jam to minimize future flooding hazards. Volumetric calculation of Z-polygons were calculated at increments of 0.1 meter elevation from the minimum to maximum levels within the DEMs allowing simulation of water volumes at different flood levels. Water flood simulation in an Air-LiDAR DEM allows very accurate determination of flood trigger levels for segments between channel obstructions. The study area comprises three sections (A, B, and C) of the lower Mohawk River starting at the Rail Bridge above the New York State Canal System Lock 9 (E9 Lock), including the Boston and Maine (B&M) Rail Bridge at the Schenectady International (SI) Plant, and ending at the Interstate 890 Bridge. Area B, between Lock 9 and the SI Plant, is notorious for ice jams, including one that resulted in a major flooding event on January 25th, 2010 (Marsellos et al., 2010). To understand when river flooding occurs flood trigger levels need to be determined. Flood trigger levels of river elevation were found for the sections preceding area A and following area C of the 2010 flooded area B to determine the stage elevations at which up stream water builds up due to ice jam and flooding occurs. Beginning from area A, Rail Bridge to Lock 9, the trigger flood level is at 72.3 ± 0.1meters. This river section of 2.27 kilometer length indicates a shallow gradient, suggestive of a U-shaped riverbed, and the water level increased smoothly decreasing the chance of ice jams. In 2010, the flood trigger level for area B is at 70.7 meters. At the area C, below the B&M Railroad to Interstate 890 Bridge the flood trigger level is at 69.3 ± 0.1 meters. River sections B and C display a steeper gradient, suggestive of a V-shaped riverbed due to knickpoint erosion deepening the river basin. Constrained river areas of B and C show similar water flood simulation graphs and could be prone to ice-jams, while area A appears as less possible for future ice jams. ( en )

Subjects/Keywords: Bridge railings; Canal locks; Digital elevation models; Floods; Ice; Polygons; Rivers; Simulations; Surface areas; Topographical elevation; Flood control; Floods; Ice; New York (State) – Mohawk River

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Foster, J. (2012). Incremental volumetric calculation using LiDAR and GIS : A methodology for predicting flood trigger levels. (Thesis). University of Florida. Retrieved from http://ufdc.ufl.edu/AA00061000

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Foster, Jessica. “Incremental volumetric calculation using LiDAR and GIS : A methodology for predicting flood trigger levels.” 2012. Thesis, University of Florida. Accessed December 15, 2019. http://ufdc.ufl.edu/AA00061000.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Foster, Jessica. “Incremental volumetric calculation using LiDAR and GIS : A methodology for predicting flood trigger levels.” 2012. Web. 15 Dec 2019.

Vancouver:

Foster J. Incremental volumetric calculation using LiDAR and GIS : A methodology for predicting flood trigger levels. [Internet] [Thesis]. University of Florida; 2012. [cited 2019 Dec 15]. Available from: http://ufdc.ufl.edu/AA00061000.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Foster J. Incremental volumetric calculation using LiDAR and GIS : A methodology for predicting flood trigger levels. [Thesis]. University of Florida; 2012. Available from: http://ufdc.ufl.edu/AA00061000

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

3. Sharma Subedi, Abhijit. Quantification of the Effect of Bridge Pier Encasement on Headwater Elevation Using HEC-RAS.

Degree: MSin Engineering, Department of Civil/Environmental and Chemical Engineering, 2017, Youngstown State University

Bridges are one of the most expensive and vital infrastructures in the transportation system. However, the bridge substructure such as piers, undergoes various kinds of deterioration and damages overtime. Different kinds of repair and rehabilitation practices are needed to protect bridges from future damages. One of such common methods of pier protection is pier encasement. Pier encasement involves enclosing an existing pier with suitable materials such as PVC pipe, to increase its strength. However, the process of pier encasement increases the overall width of the pier, which might result in the rise of headwater elevation at the bridge vicinity. Moreover, this rise in headwater elevation may cause serious problems in areas located in high-risk flood zones. When the bridge and its piers are located within the defined floodway boundaries of a Federal Emergency Management Administration (FEMA) National Flood Insurance Program (NFIP) Zone AE, no rise in water surface elevation must be maintained. Therefore, this study was undertaken to find the effects of pier encasement on headwater elevation under varying pier and channel configurations. In order to study the impact of pier encasement, HEC-RAS, was used for hydraulic simulation. The hydraulic simulation was carried out for various channel configurations. The comparison was done for encased and non-encased pier conditions for the varying conditions of channel configurations, such as channel width, slope, and flow volume. The study showed the rise in headwater elevation for the channel with a smaller bottom width (20 ft, 40 ft, 60 ft, and 80 ft). The rise in headwater elevation was further increased for steeper slopes (0.7% and 1.0%) and for higher flow volume.Furthermore, winter ice jam around a bridge structure can cause serious damage to the bridge and has been one of the major problems with bridges in the northern belt of the USA. The bridge piers, which comes in contact with ice, has a significant impact on ice jam. Moreover, a bridge pier enforces substantial changes in river flow dynamics, especially in ice jam conditions. Therefore, the effect of pier encasement on water surface elevation during the winter period (ice jam) was also analyzed using HEC-RAS. After running numerous models with various channel configurations, it was found that the pier encasement effect was minimal in head water elevation even for the ice jammed bridges. Nevertheless, the minor rise was noticed for smaller channel bottom widths (20 ft and 40 ft) only with steeper slope (0.7% and 1.0%).Since these findings were derived using various hypothetical channel configurations, the further application of this study was pursued in various existing bridges in the Grand River, OH, to verify that the concept derived from the generic channel section is valid in real word applications. The pier encasement was done for bridges located on the Grand River. The hydraulic simulation was conducted for computing water surface elevation for both encased and non-encased bridge structures. The result was… Advisors/Committee Members: Sharma, Suresh (Advisor).

Subjects/Keywords: Civil Engineering; Climate Change; Environmental Engineering; Water Resource Management; Transportation; Rehabilitation; Pier; Pier encasement; HEC-RAS; Bridges; Transportation; Grand River; Water surface elevation; Headwater elevation; Structures; FEMA; Winter ice jam; Bridge deterioration; Rehabilitation; NFIP; Slope; Channel bottom width; Generic channel section; River

river ice jam in cold regions of the United States has always been a great matter of concern… …especially for the river infrastructures, such as bridges. Ice jam and ice accumulations incur an… …on water surface elevation due to winter ice cover and ice jams using HEC-RAS model; III… …simulation and record the water surface elevation; c. Conduct a study for two scenarios with ice… …jam and without ice jam; d. Compare and analyze the water surface elevation recorded in both… 

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Sharma Subedi, A. (2017). Quantification of the Effect of Bridge Pier Encasement on Headwater Elevation Using HEC-RAS. (Masters Thesis). Youngstown State University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=ysu1502982013572665

Chicago Manual of Style (16th Edition):

Sharma Subedi, Abhijit. “Quantification of the Effect of Bridge Pier Encasement on Headwater Elevation Using HEC-RAS.” 2017. Masters Thesis, Youngstown State University. Accessed December 15, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1502982013572665.

MLA Handbook (7th Edition):

Sharma Subedi, Abhijit. “Quantification of the Effect of Bridge Pier Encasement on Headwater Elevation Using HEC-RAS.” 2017. Web. 15 Dec 2019.

Vancouver:

Sharma Subedi A. Quantification of the Effect of Bridge Pier Encasement on Headwater Elevation Using HEC-RAS. [Internet] [Masters thesis]. Youngstown State University; 2017. [cited 2019 Dec 15]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=ysu1502982013572665.

Council of Science Editors:

Sharma Subedi A. Quantification of the Effect of Bridge Pier Encasement on Headwater Elevation Using HEC-RAS. [Masters Thesis]. Youngstown State University; 2017. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=ysu1502982013572665

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