The Experts below are selected from a list of 52251 Experts worldwide ranked by ideXlab platform
Donald O Rosenberry - One of the best experts on this subject based on the ideXlab platform.
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a Seepage meter designed for use in flowing water
Journal of Hydrology, 2008Co-Authors: Donald O RosenberryAbstract:Summary Seepage meters provide one of the most direct means to measure exchange of water across the sediment–water interface, but they generally have been unsuitable for use in fluvial settings. Although the Seepage bag can be placed inside a rigid container to minimize velocity head concerns, the Seepage cylinder installed in the sediment bed projects into and disrupts the flow field, altering both the local-scale fluid exchange as well as measurement of that exchange. A low-profile Seepage meter designed for use in moving water was tested in a Seepage meter flux tank where both current velocity and Seepage velocity could be controlled. The conical Seepage cylinder protrudes only slightly above the sediment bed and is connected via tubing to a Seepage bag or flowmeter positioned inside a rigid shelter that is located nearby where current velocity is much slower. Laboratory and field tests indicate that the net effect of the small protrusion of the Seepage cylinder into the surface water flow field is inconsequentially small for surface water currents up to 65 cm s −1 . Current velocity affects the variability of Seepage measurements; Seepage standard deviation increased from ∼2 to ∼6 cm d −1 as current velocity increased from 9 to 65 cm s −1 . Substantial bias can result if the shelter is not placed to minimize hydraulic gradient between the bag and the Seepage cylinder.
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Integrating Seepage heterogeneity with the use of ganged Seepage meters
Limnology and Oceanography: Methods, 2005Co-Authors: Donald O RosenberryAbstract:The usefulness of standard half-barrel Seepage meters for measurement of fluxes between groundwater, and surface water is limited by the small bed area that each measurement represents and the relatively large associated labor costs. Standard half-barrel cylinders were ganged together to allow one measurement of the summed Seepage through all of the meters, reducing labor cost and increasing the representative area of measurement. Comparisons of ganged versus individual-meter measurements at two lakes, under both inSeepage and outSeepage conditions, indicate little loss of efficiency resulting from routing Seepage water through the ganging system. Differences between summed and ganged Seepage rates were not significant for all but the fastest rates of Seepage. At flow rates greater than about 250 mL min−1, ganged values were as low as 80% of summed values. Gangedmeter head losses also were calculated to determine their significance relative to hydraulic-head gradients measured at the field sites. The calculated reduction in hydraulic gradient beneath the Seepage meters was significant only for the largest measured Seepage rates. A calibration tank was used to determine single-meter and gangedmeter efficiencies compared to known Seepage rates. Single-cylinder Seepage meters required an average correction factor of 1.05 to convert measured to actual values, whereas the ganged measurements made in the tank required a larger correction factor of 1.14. Although manual measurements were used in these tests, the concept of ganging Seepage cylinders also would be useful when used in conjunction with automated flowmeters.
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Use of an electromagnetic Seepage meter to investigate temporal variability in lake Seepage.
Ground water, 2004Co-Authors: Donald O Rosenberry, Roger H. MorinAbstract:A commercially available electromagnetic flowmeter is attached to a Seepage cylinder to create an electromagnetic Seepage meter (ESM) for automating measurement of fluxes across the sediment/water interface between ground water and surface water. The ESM is evaluated through its application at two lakes in New England, one where water seeps into the lake and one where water seeps out of the lake. The electromagnetic flowmeter replaces the Seepage-meter bag and provides a continuous series of measurements from which temporal Seepage processes can be investigated. It provides flow measurements over a range of three orders of magnitude, and contains no protruding components or moving parts. The ESM was used to evaluate duration of Seepage disturbance following meter installation and indicated natural Seepage rates resumed approximately one hour following meter insertion in a sandy lakebed. Lakebed Seepage also varied considerably in response to lakebed disturbances, near-shore waves, and rainfalls, indicating hydrologic processes are occurring in shallow lakebed settings at time scales that have largely gone unobserved.
Yoshiaki Fukuo - One of the best experts on this subject based on the ideXlab platform.
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continuous measurements of ground water Seepage using an automatic Seepage meter
Ground Water, 1993Co-Authors: Makoto Taniguchi, Yoshiaki FukuoAbstract:An automatic Seepage meter using a heat pulse method was developed to obtain a continuous measurement of ground-water Seepage rates. According to calibrations of the automatic Seepage meter fitted with a 50 cm diameter collection funnel, Seepage rates from 2 X 10-5 to 5 X 10-4 cm/sec can be obtained by measuring the time when the temperature as measured by a thermistor peaks after applying a heat pulse. The automatic Seepage meter was used to measure continuous Seepage rates into Lake Biwa, Japan. The ground-water Seepage rate measured by the automatic Seepage meter in Lake Biwa changed by six times within 12 hours. The automatic Seepage meter is useful for surface-/ground-water studies, because a continuous Seepage rate can be obtained without errors caused by the resistance of a collection bag to water flow.
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Continuous Measurements of Ground‐Water Seepage Using an Automatic Seepage Meter
Ground Water, 1993Co-Authors: Makoto Taniguchi, Yoshiaki FukuoAbstract:An automatic Seepage meter using a heat pulse method was developed to obtain a continuous measurement of ground-water Seepage rates. According to calibrations of the automatic Seepage meter fitted with a 50 cm diameter collection funnel, Seepage rates from 2 X 10-5 to 5 X 10-4 cm/sec can be obtained by measuring the time when the temperature as measured by a thermistor peaks after applying a heat pulse. The automatic Seepage meter was used to measure continuous Seepage rates into Lake Biwa, Japan. The ground-water Seepage rate measured by the automatic Seepage meter in Lake Biwa changed by six times within 12 hours. The automatic Seepage meter is useful for surface-/ground-water studies, because a continuous Seepage rate can be obtained without errors caused by the resistance of a collection bag to water flow.
Zhu Yue - One of the best experts on this subject based on the ideXlab platform.
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Practice in Seepage prevention structures of roller-compacted concrete dams
Journal of Hehai University, 2003Co-Authors: Zhu YueAbstract:In consideration of the Seepage properties of rollercompacted concrete dams (RCCDs) and the complicacy of Seepagecontrol design, an introduction is given to the practice in Seepage prevention structures and their performances in projects of some existing dams at home and abroad. The main advantages and disadvantages of some typical Seepage prevention structures are analyzed through comparison. Finally, an optimum Seepage prevention structure for RCCDs is recommended, which can bring the main advantages of rollercompacted concrete construction into full play.
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On Seepage Prevention Structure of High Roller-compacted-concrete Gravity Dams
Hongshui River, 2001Co-Authors: Zhu YueAbstract:Taking into account of the Seepage properties of roller compacted concrete and the design criteria for Seepage prevention and control of roller compacted concrete dams, in this present paper the authors mainly focus on the study on types of Seepage prevention structures of roller compacted concrete dams.At first,the main typical Seepage prevention structures practically adopted are introduced and interpreted,then by comparison of analyses and the authors' knowledge gotten from their own research work for many years in this area,the authors recommend optimum types of the Seepage prevention structures for high roller compacted concrete gravity dams.They could essentially meet the demands of Seepage control and make rapid construction of roller compacted concrete dams be brought to full play.Finally,two different structural design schemes for the Seepage control are recommended.
Makoto Taniguchi - One of the best experts on this subject based on the ideXlab platform.
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continuous measurements of ground water Seepage using an automatic Seepage meter
Ground Water, 1993Co-Authors: Makoto Taniguchi, Yoshiaki FukuoAbstract:An automatic Seepage meter using a heat pulse method was developed to obtain a continuous measurement of ground-water Seepage rates. According to calibrations of the automatic Seepage meter fitted with a 50 cm diameter collection funnel, Seepage rates from 2 X 10-5 to 5 X 10-4 cm/sec can be obtained by measuring the time when the temperature as measured by a thermistor peaks after applying a heat pulse. The automatic Seepage meter was used to measure continuous Seepage rates into Lake Biwa, Japan. The ground-water Seepage rate measured by the automatic Seepage meter in Lake Biwa changed by six times within 12 hours. The automatic Seepage meter is useful for surface-/ground-water studies, because a continuous Seepage rate can be obtained without errors caused by the resistance of a collection bag to water flow.
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Continuous Measurements of Ground‐Water Seepage Using an Automatic Seepage Meter
Ground Water, 1993Co-Authors: Makoto Taniguchi, Yoshiaki FukuoAbstract:An automatic Seepage meter using a heat pulse method was developed to obtain a continuous measurement of ground-water Seepage rates. According to calibrations of the automatic Seepage meter fitted with a 50 cm diameter collection funnel, Seepage rates from 2 X 10-5 to 5 X 10-4 cm/sec can be obtained by measuring the time when the temperature as measured by a thermistor peaks after applying a heat pulse. The automatic Seepage meter was used to measure continuous Seepage rates into Lake Biwa, Japan. The ground-water Seepage rate measured by the automatic Seepage meter in Lake Biwa changed by six times within 12 hours. The automatic Seepage meter is useful for surface-/ground-water studies, because a continuous Seepage rate can be obtained without errors caused by the resistance of a collection bag to water flow.
Xiaotong Yang - One of the best experts on this subject based on the ideXlab platform.
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Experimental Study of Leakage Monitoring of Diaphragm Walls Based on Distributed Optical Fiber Temperature Measurement Technology.
Sensors, 2019Co-Authors: Zhong-nian Yang, Qingsheng Meng, Haotong Wang, Yuqian Zheng, Xiaotong YangAbstract:In geotechnical engineering Seepage of diaphragm walls is an important issue which may cause engineering disasters. It is therefore of great significance to develop reliable monitoring technology to monitor the leakage. The purpose of this study is to explore the application of a distributed optical fiber temperature measurement system in leakage monitoring of underground diaphragm walls using 1 g model tests. The principles of Seepage monitoring based on distributed optical fiber temperature measurement technology are introduced. Fiber with heating cable was laid along the wall to control Seepage flow at different speeds. The temperature rise of the fiber during Seepage was also recorded under different heating power conditions. In particular the effect of single variables (Seepage velocity and heating power) on the temperature rise of optical fibers was discussed. Test results indicated that the temperature difference between the Seepage and non-Seepage parts of diaphragm wall can be monitored well using fiber-optic external heating cable. Higher heating power also can improve the resolution of fiber-optic Seepage. The Seepage velocity had a linear relationship with the final stable temperature after heating, and the linear correlation coefficient increases with the increase of heating power. The stable temperature decreased with the increase of flow velocity. The findings provide a basis for quantitative measurement and precise location of Seepage velocity of diaphragm walls.
