An alternative method to overcome the high cost and time required for the design, analysis, construction and operating of a conventional water control structure is an inflatable dam. The basic aim of this project is to study both theoretically and experimentally the behaviour and performance of inflatable dams under hydrostatic and hydrodynamic conditions and to develop a design method. A finite element approach is developed in order to analyse air, water and a combination of air and water inflated dams to determine the shape and tension of the membrane of the dam under hydrostatic and hydrodynamic conditions. A series of models of inflatable dams were constructed and tested under hydrostatic and hydrodynamic conditions. The shapes of these models were compared with the theoretical shapes obtained from the theoretical analysis. The comparison shows there was a good relationship between the experimental and theoretical shapes. A new formula was derived for calculating the rate of flow over the air, water and air/water inflated dams theoretically. This develops the potential for applying an inflatable dam as a device for measuring discharge. A design technique for a dam was developed to design air, water and air/water inflated dams under hydrostatic conditions. This,technique can be used for the design of dams with different geometry of base length. computer programs were written for the analysis and design of the dams based on the finite element approach and considerable efforts were undertaken to simplify the input data and the output results. A sub-program was developed to provide the results in graphic form if required.

Manitoba Hydro owns and operates 12 river hydroelectric generating stations ans two major control structures. The structures control the flow of water almost exclusively with gate wheels. It is important for the roller paths to remain true to allow uniform distribution of the hydraulic load on the gates to the gate wheels. Manitoba Hydro is currently replacing the distorted steel roller paths at its MacArthur Generating Station. The purpose of this study was to evaluate the physical properties of high strength proprietary grouts to determine their adequacy for use beneath new roller paths of water control gates which have unusual spacial constraints. Two full size mockups of a portion of an existing guide, with a steel overlay, were utilized in the experimental study. To investigate the stress-strain distribution in the mockup under specific loading condition, strain gauges were installed on both of the web sides of the embedded steel I-beam: one group of gauges was located just below the flange, the others were located along the mid-hight of the beam web. Force gauges were inserted to measure the pressure between the thin grout layer bottom and the top of the embedded I-beam. A special LVDT (linear variable differential transducer) assembly was made to measure the maximum displacement of grout layer. Mockup samples were subjected to static and cyclic loading procedures at two designated loading points. The grout cylindrical creep tests were conducted at the same time. It included tests at room temperature and at the elevated temperature of 50°C. The initial sustained load was 50% of the ultimate compression strength of the grout cylinder (3"x6"). Once the creep development was observed to become constant, the sustained load was raised up to 70% of ultimate strength and held constant until the end of the test. The test results indicate that the strength of the proposed grouting material is adequate to resist the required load, both statically and cyclically. Temperature has no significant effects on this specific loading situation. The proposed grouting method is proven to be simple, economic and efficient, therefore, the technique is suitable for roller path repairing.

Title from PDF of title page. / Document formatted into pages; contains 71 pages. / Thesis (M.S.)--University of South Florida, 2003. / Includes bibliographical references. / Text (Electronic thesis) in PDF format. / ABSTRACT: Thalassia testudinum, a stenohaline seagrass species, and Ruppia maritima, a euryhaline submerged aquatic vegetation species, were subjected to the same seven salinity levels (0 - 60) in a controlled environment. The response variables examined were the occurrence of leaf discoloration, plant growth rates, photosynthetic characteristics of blade segments (Pmax, respiration, alpha, and Ik), and osmolality changes within the plant tissues. These response variables were measured at exposure times of one, seven, and 28 days. Greater than 75% leaf discoloration occurred in Thalassia testudinum blades placed in 0, and 60 psu, while Ruppia maritima blades only became severely discolored in 60 psu. Plant growth rates were highest in 40 psu for T. testudinum and 20 psu for R. maritima. Pmax for both species was somewhat affected by salinity changes, but the plants did not appear to be photosynthetically compromised in their "optimal" ranges over time. / ABSTRACT: Salinity effects on photosynthesis were less pronounced in R. maritima than in T. testudinum, which would be expected when comparing a euryhaline species to a stenohaline species. Both intercellular and intracellular osmolality showed a pattern of increase or decrease as the treatment salinities were altered from ambient levels (30 psu for T. testudinum and 20 psu for R. maritima). After one day of exposure to a new treatment salinity, the intercellular osmolality had changed significantly from ambient value, with a second shift, occurring mostly in the salinity extremes, for both seagrass species. This second shift is most likely due to the fact that at the extremes, the plants are being compromised. Changes in these physical and physiological responses indicate that significant increases and decreases in ambient salinity levels are initially stressful for both species. / ABSTRACT: Both seagrass species had an optimal salinity as well as a range of salinities in which the long-term physiological stresses did not cause tissue death. Thalassia testudinum had the fewest stress responses in 40 psu, with an optimal range of 20 - 40 psu. Ruppia maritima had the fewest stress responses in 20 psu (growth salinity) with an optimal range of 0 - 40 psu. In this study, neither species was able to survive for 28 days in 60 psu (at which point the plants had been out of their respective optimal salinities for at least 42 days). / System requirements: World Wide Web browser and PDF reader. / Mode of access: World Wide Web.

Thesis (M. Sc.)--University of Hong Kong, 1996. / Includes bibliographical references (leaf 87-94).

Thalassia testudinum, a stenohaline seagrass species, and Ruppia maritima, a euryhaline submerged aquatic vegetation species, were subjected to the same seven salinity levels (0 - 60) in a controlled environment. The response variables examined were the occurrence of leaf discoloration, plant growth rates, photosynthetic characteristics of blade segments (Pmax, respiration, alpha, and Ik), and osmolality changes within the plant tissues. These response variables were measured at exposure times of one, seven, and 28 days. Greater than 75% leaf discoloration occurred in Thalassia testudinum blades placed in 0, and 60 psu, while Ruppia maritima blades only became severely discolored in 60 psu. Plant growth rates were highest in 40 psu for T. testudinum and 20 psu for R. maritima. Pmax for both species was somewhat affected by salinity changes, but the plants did not appear to be photosynthetically compromised in their "optimal" ranges over time. Salinity effects on photosynthesis were less pronounced in R. maritima than in T. testudinum, which would be expected when comparing a euryhaline species to a stenohaline species. Both intercellular and intracellular osmolality showed a pattern of increase or decrease as the treatment salinities were altered from ambient levels (30 psu for T. testudinum and 20 psu for R. maritima). After one day of exposure to a new treatment salinity, the intercellular osmolality had changed significantly from ambient value, with a second shift, occurring mostly in the salinity extremes, for both seagrass species. This second shift is most likely due to the fact that at the extremes, the plants are being compromised. Changes in these physical and physiological responses indicate that significant increases and decreases in ambient salinity levels are initially stressful for both species. Both seagrass species had an optimal salinity as well as a range of salinities in which the long-term physiological stresses did not cause tissue death. Thalassia testudinum had the fewest stress responses in 40 psu, with an optimal range of 20 - 40 psu. Ruppia maritima had the fewest stress responses in 20 psu (growth salinity) with an optimal range of 0 - 40 psu. In this study, neither species was able to survive for 28 days in 60 psu (at which point the plants had been out of their respective optimal salinities for at least 42 days).

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Based on the de St Venant Equations, the Preissmann's implicit finite difference scheme, and the double sweep algorithm, a mathematical model for one-dimensional subcritical unsteady flow in the Third Navigation Channel at the Gezhouba Water Control Project, China, has been developed. The model has been calibrated and verified using the prototype test data. All conceivable factors affecting wave propagation have been studied parametrically. The side discharge method is considered to be the best way to reduce the amplitudes of both water surface elevation and velocity variations caused by unsteady flow due to the emptying of the lock chamber. Using side discharges to distribute the discharge from the lock chamber along the channel, instead of concentrated discharge at the upstream boundary, improves greatly the navigation conditions. / Master of Science

För att ta fram vårflodsprognoser används idag en hydrologisk modell, HBVmodellen, som används operationellt både i Sverige och i andra länder för att ta fram tillrinningsprognoser. Ett av problemen med dessa prognoser är dock att de ofta har felaktigheter i beräkning av tillrinningsvolymer. I den här studien undersöks Vängelsjöns delavrinningsområde. Ett prognosområde där HBV-modellens tillrinningsprognos tidigare gett stora volymfel. Rapporten undersöker därför om det går att korrigera den operationella modellens snömängd genom snödjupsobservationer, för att ta fram mer tillförlitliga vårflodsprognoser. I rapporten har snödjupsobservationer och densitetsmätningar från Vattenregleringsföretagen (VRF), tillsammans med snödjupsobservationer från Sveriges meteorologiska och hydrologiska institut (SMHI), analyserats för att se om de kan användas för att förbättra tillrinningsprognosen för Vängelsjöns delavrinningsområde. Studien visar att det finns potential till att använda snödjupsobservationer för att minska osäkerheter i tillrinningsprognosen för Vängelsjöns delavrinningsområde. Det bästa resultatet gavs genom att använda tre stationer från SMHI tillsammans med två stationer från VRF. Resultatet för dessa fem stationer gav ett volymfel i uppmätt vattenekvivalent på 6 %, 7 %, 22 % och 17 % för mars månad perioden 2014-2017, vilket gav en markant förbättring mot det modellerade prognosvärdet med volymfel på 40 %, 77 %, 24 %, och 49 % för samma period. / Today, spring flood forecasts are calculated through a hydrological model, the HBVmodel. It is a model that is used operationally both in Sweden and in other countries to obtain catchment forecasts. One problem with these forecasts is that they often give errors in calculations to the inflow volume. In this study the Vängelsjö sub catchment will be examined. A forecast area where the HBV-model flow forecasting has given large volume errors. In the report it is therefore examined if the operational model can be corrected with snow measurement data. In this report snow depth observations and density measurements from Vattenregleringsföretagen (VRF) have been analyzed, together with snow depth observations from the Swedish Institute for Meteorology and Hydrology (SMHI) to see if the data can be used to improve the forecasting for Vängelsjö sub catchment. The study shows that there is a potential in using snow measurement observations to reduce insecurities in the flow forecast for Vängelsjö sub catchment. The best result was received by using three snow stations from SMHI and two from VRF. The result from those five stations gave a volume error in measured snow water equivalent (SWE) at 6 %, 7 %, 22% and 17 % for Mars during the period 2014-2017, which gave a significant improvement against the modelled forecast value with volume errors of 40 %, 77 %, 24 % and 49 % for the same period.