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Modeling the hydraulic characteristics of fully developed flow in corrugated steel pipe culvertsToews, Jonathan Scott 25 September 2012 (has links)
The process of fish migration within rivers and streams is important, especially during the spawning season which often coincides with peak spring discharges in Manitoba. Current environmental regulations for fish passage through culverts require that the average velocity be limited to the prolonged swimming speed of the fish species present. In order to examine the validity of this approach, physical model results were used to calibrate and test a commercially available Computational Fluid Dynamics (CFD) model.
Detailed analysis showed that CFD models and the empirical equations used were both able to give a better representation of the flow field than the average velocity. However, the empirical equations were able to provide a more accurate velocity distribution within the fully developed region. A relationship was then developed, to estimate the cumulative percent area less than a threshold velocity within CSP culverts, to be used as a guideline during the design phase.
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A Bayesian network for prioritizing restoration of aquatic connectivity /Andersen, Eric J. (Eric John). January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2011. / Printout. Includes bibliographical references (leaves 60-67). Also available on the World Wide Web.
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Fish Passage Through Rehabilitated Culverts Laboratory StudyOlsen, Amber H. 01 December 2011 (has links)
Culverts are rehabilitated using a variety of techniques; the approach studied in this report focuses on the use of slip liners. Slip lining refers to installing a liner pipe inside a host pipe to extend its useful life. Slip lining reduces the diameter of the culvert; however, when a smooth-walled liner [e.g., high-density polyethylene (HDPE)] is installed in a profiled-wall pipe (e.g., corrugated metal pipe), the reduction in hydraulic roughness helps to compensate for the reduction in flow area, minimizing any reduction in discharge capacity. In some cases, the discharge capacity may increase. A smaller diameter liner, made of smoother material, will likely produce larger pipe flow velocities relative to the host culvert. High velocities can potentially create a barrier for fish passage, discouraging their use in areas sensitive to fish passage.
The objective of this research was to find ways to implement slip liners and still accommodate fish passage. A 60-ft long, 2-ft diameter, baffled slip liner was tested at seven slopes (0-3.5%) and at three flow rates per slope (1-4.6 cfs). For comparison purposes, tests were also conducted on a smooth-walled (non-baffled) liner. Baffles were found to greatly increase the potential for low-flow fish passage, allowing passage up to slopes of 3.5%. Conversely, the smooth-walled liner prohibited passage beyond a 1.0% slope.
The potential drawback to using baffles in a slip-lined culvert is the reduction in culvert flow capacity. Compared to the smooth-walled liner, the baffled culvert reduced the flow capacity of the culvert by about 74% at pressurized, full pipe flow.
Finally, velocity was measured with an acoustic Doppler velocimeter (ADV) in the baffled culvert and turbulence values were calculated using four different methods. The Energy Dissipation Factor, or EDF, values had a close relationship with percent fish passing and if more testing is done, it could be used as a scaling factor to transfer fish passage data to other sized culverts. The results of this study, suggest that baffled slip-lined culverts can aid fish passage and are useful for culvert rehabilitation as long as the culvert can still maintain appropriate flow capacity.
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Longitudinal Processes in Stream Ecosystems: Examining Connections between Stream Characteristics at a Reach-scaleHintz, Chelsea 25 May 2022 (has links)
No description available.
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Analysis and design of box culvertsAbdel-Haq, Ali H. January 1987 (has links)
No description available.
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Variation of Manning’s Roughness Coefficient with Diameter, Discharge, Slope and Depth in Partially Filled HDPE CulvertsDevkota, Jay P. 03 July 2012 (has links)
No description available.
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ASSESSMENT OF DETERIORATED CORRUGATED STEEL CULVERTSMAI, VAN THIEN 31 January 2013 (has links)
The goal of this thesis is to develop more effective quantitative procedures to evaluate the stability of deteriorated metal culverts and a better understanding of the deteriorated culverts' behaviour through non-destructive testing, full scale experiments and numerical analyses. First, three design cases were examined using numerical analysis to study the effects of corrosion, burial depth and staged construction on the capacity of deteriorated steel culverts. Then, a method to measure the remaining wall thickness of two 1.8 m diameter corroded metal culverts using ultrasonic device was developed. Both culverts were then buried in the test pit at Queen's University and tested under nominal and working vehicle loads at 0.9m cover and 0.6m cover. The more heavily corroded structure (CSP1) was tested up to its ultimate limit state, inducing local bending across the crown, as well as local buckling of the remnants of the corrugated steel wall between perforations at the haunches. The results suggest that the single axle pads interact to influence the culvert's behaviour despite the shallow cover used in these experiments. CSP1 was able to carry the working load and did not fail until reaching 340 kN, which was equal to 90% of the fully factored load. The experiment suggests that less deteriorated metal culverts (as compared to CSP1) may have the required capacity. Two finite element packages, CANDE and ABAQUS, were used to perform the numerical investigation and the AASHTO and CHBDC approaches were then used to calculate the thrust force in the culverts. Although the numerical analysis produced conservative values for the thrust forces, it failed to capture the non-linear behaviour of both specimens in the experiments. Both the AASHTO and the CHBDC approaches produced unconservative thrust forces compared to experimental results while numerical analysis using Moore's spreading factor produced the most conservative results in terms of thrust. The analysis suggests that CANDE could be used to predict thrust forces in less deteriorated metal culverts. A procedure to assess the stability of deteriorated corrugated metal culverts based on quantitative data was developed using the numerical analysis and experimental results. / Thesis (Master, Civil Engineering) -- Queen's University, 2013-01-30 12:56:17.945
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Corrosion Evaluation and Durability Estimation of Aluminized Steel Drainage PipesAkhoondan, Mersedeh 01 January 2012 (has links)
Aluminized steel pipes are expected to have a long service life, e.g. 75 years. Spiral ribbed aluminized pipes (SRAP) have been widely specified and used by the Florida Department of Transportation (FDOT) for drainage of runoff water. Confidence in the long term durability of SRAP has been challenged by recent unexpected early corrosion failures in various Florida locations. SRAP premature corrosion incidents have occurred in two modalities. Mode A has taken place in near-neutral soil environments and has often been associated with either gross manufacturing defects (i.e. helical cuts) or corrosion concentration at or near the ribs. Mode B took place in pipes in contact with limestone backfill and corrosion damage was in the form of perforations, not preferentially located at the ribs, and not necessarily associated with other deficiencies. These failures motivated this research. The objectives of this work are to establish to what extent the Mode A corrosion incidents can be ascribed to manufacturing defects, that can be rectified by appropriate quality control, as opposed to an intrinsic vulnerability to corrosion of regularly produced SRAP due to ordinary forming strains and to determine the mechanism responsible for Mode B corrosion including the role that limestone backfill played in that deterioration. To achieve those objectives, laboratory experiments were conducted to replicate the conditions for Mode A and Mode B. Overall, the findings of this and previous work suggest that much of the corrosion damage observed in the Mode A incidents were promoted more by manufacturing deficiencies and less by any possible inherent susceptibility of corrosion at the ribs of SRAP that was produced following appropriate quality control. Experiments to explore the causes of Mode B corrosion showed that high pH values, sufficient to cause dissolution of the passive film on aluminum, can develop under exposure of limestone to flowing natural water. The findings substantiate, for the first time, an important vulnerability of aluminized steel in limestone soils and provide an explanation for the rapid onset deterioration observed at the field under Mode B. The findings also provide strong evidence in support of service guidelines to disallow the use of limestone bedding for aluminized steel pipe, including SRAP.
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Joniškio, Mažeikių ir Telšių rajonuose esančių melioracijos griovių būklės tyrimai / Condition state of melioratio channels in Joniskis, Mazeikiai and Telsiai districtRiauba, Vilius 08 August 2007 (has links)
Straipsnyje apibendrinami melioracijos griovių ir reguliuotų upelių būklės dviejų metų tyrimų duomenys. Nustatyta, kad didžiausios deformacijos vyksta griovio dugne ir šlaitų papėdėje. Daugiausia griovys deformuojasi dėl dugne besikaupiančių sąnašų – nevalomas griovys seklėja, lėkštėja jo šlaitai. Atliekant tyrimus buvo nustatomos šios melioracijos griovių charakteristikos: bendras ilgis, plotis, šlaitų nuolydis, dugno plotis, gylis, sąnašų kiekis griovyje, šlaitų apaugimas krūmais; griovyje esančių įrenginių charakteristikos: drenažo žiočių būklė, pralaidų būklė. Tyrimo metu ištirta 171,1 km melioracijos griovių, 199 pralaidos, 1951 drenažo žiotys, esančių Joniškio, Mažeikių ir Telšių rajonuose. Tyrimai atlikti 2005 , 2006 metais. Buvo tirti tik blogos būklės grioviai. Darbo tikslas – įvertinti Joniškio, Mažeikių ir Telšių rajonuose esančių melioracijos griovių ir jų įrenginių esamą būklę. Nustatyta, kad vyraujančios tyrinėjamų griovių deformacijos yra šlaitų apaugimas įvairaus tankumo krūmais, dugno uždumblėjimas, vandens augmenijos priaugimas, bebrų ir kitų žvėrelių išrausiojimai. Hidrotechninių statinių (pralaidų) esamos deformacijos: netinkamos kelio dangos, netvarkingi sargšuliai, blogos būklės antgaliai, vamzdžių sandūrose atsiradę tarpai, pralaidose susikaupusios sąnašos. Drenažo žiočių esamos deformacijos: po sąnašomis, po velėną, užaugusios krūmų ir žolių šaknimis, sulūžusios, atitrūkusios. / Data from a 2 years study of drainage channels and canalized rivulets are summarized in this paper. It was observed that the majority of information processes occur on the bottom of channels and on channels slopes. In most cases channels are deformated due to the deposit, which accumulate on the bottom, and, if no desilting is executed, channel (where a thick layer of silt exists), the channel profile becomes irregular and unstable.
The following characteristics of these drainage channels where determined when carrying out the investigations: general length, width, slopes pitch, bottom width, depth, deposit amounts in drainage channels, slopes shrubby; in channel structures characteristics: the outlets of drainage condition, the water culverts condition.
In Joniškis district explore 171,1 km drainage channels, 199 water culverts, 1951 drainage outlets where investigated in 2005, 2006. The drainage channels are under bad conditions.
The aim of the work is to evaluate state of drainage channels and its structures in the territory of the Joniškis district. The drainage channels the slopes are overgrown with a medley shrubbery, the drainage channels bottom silt up, water plants growth, beaver and other animal damage. Water culverts deformation is: low keep paving, bad condition of pipe heads, joint tightness, out of order staves, in water culverts to make a collection deposit. The deformation of drainage outlets is: under deposit, under the sod, the rank scrub and grass roots... [to full text]
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Klaipėdos rajono melioruotų žemių ir melioracijos statinių būklė / Condition Of Reclaimed Lands And Reclamation Constructions In Klaipėda DistrictKondrotavičienė, Giedrė 15 June 2010 (has links)
Magistrantūros studijų baigiamajame darbe analizuojama Klaipėdos rajono melioruotų žemių ir melioracijos statinių būklė. Darbo apimtis 48 puslapiai kompiuteriu spausdinto teksto, įskaitant 2 lenteles ir 29 paveikslus. Naudotos literatūros sąrašą sudaro 21 literatūros šaltiniai.
Darbo tikslas - atlikti melioruotų žemių ir melioracijos statinių būklės analizę.
Nepriklausomybės metais, skiriant melioracijos darbams mažiau lėšų, melioracijos statinių būklė palaipsniui blogėjo. Remiantis naujausiais 2009 metų duomenimis, Klaipėdos rajone neveikiančio arba blogai veikiančio drenažo plotas sudarė 5579,28 ha, o išbrauktas iš apskaitos plotas sudarė 867,45 ha. Viso to pasekmė yra ta, kad melioruota žemė nebuvo dirbama, drenažo rinktuvai užsikimšo medžių ir augmenijos šaknimis, pamiškėje drenuoti plotai užaugo menkaverčiu mišku, krūmais.
Šiuo metu magistralinių griovių ilgis Klaipėdos rajone yra 1280 km, iš kurių 70,87 km blogos būklės. Kaip ir visi melioraciniai statiniai, taip ir grioviai nėra amžini. Nuslinkus šlaitui, nusėdus dugne nešmenims, priaugus žolių, patekus įvairiems kliuviniams, sugriuvus pralaidoms ir drenažo žiotims, grioviai praranda savo paskirtį ir patvenkia drenažo sistemas, sumažina drenažo veikimo efektyvumą, pablogindami dirbamų žemių sausėjimą. Taigi, tvarkingas griovys sąlygoja normalų vandens ištekėjimą iš drenažo žiočių ir daugeliu atvejų padeda išvengti brangių drenažo sistemos rekonstrukcijos darbų.
Lietuvoje yra 56808 pralaidų, iš kurių 23322 yra blogos... [toliau žr. visą tekstą] / In the final work of master studies, we analyse a state of reclaimed lands and reclaimation constructions in Klaipėda region. The work consists of 48 pages of printed text, including 2 tables and 29 pictures. Twenty-one references have been used.
The aim of the final work is to analyse a state of reclaimed lands and reclaimation structures.
During the years of independence, with less means being assigned for land reclamation works, the technical state of land reclamation structures gradually became worse. According to the newest inventory data of 2009, the area of badly functioning or non-functioning drainage made up 5579,28 ha, whereas the area deleted from the accounting made up 867,45 ha. Consequences of all that are: reclaimed lands were not cultivated, drainage manifolds became obstructed with roots of trees and vegetation, and the drained areas on the forest outskirts overgrew with not valuable forests and shrubs.
At present the length of main ditches in Klaipėda district is 1280 km, 70,87 km of which are in bad state. All land reclamation structures, ditches as well, are not everlasting. Ditches lose their purpose due to slope slippage, sediment deposition, grass overgrowth, and culvert or drainage mouth collapse. They overflow drainage systems as well as decrease the efficiency of drainage systems and reduce the draining of cultivated lands. Thus, ditches that are in good condition determine the regular water outflow from the drainage mouth and, in many cases help to... [to full text]
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