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An integrated suspended sediment transport monitoring and analysis concept

International Journal of Sediment Research 2014年第2期29卷 135-148页

作者： Marlene HAIMANN Marcel LIEDERMANN Petra LALK helmut habersack Christian Doppler Laboratory for Advanced Methods in River Monitoring Modelling and EngineeringInstitute of Water ManagementHydrology and Hydraulic Engineering Department of WaterAtmosphere and EnvironmentBOKU-University of Natural Resources and Life SciencesVienna

A new integrated suspended sediment monitoring strategy applying direct and indirect technologies is *** sensors continuously record the turbidity at one point in the channel cross section close to the river bank and are calibrated by water samples taken close to the *** measurements are performed to establish the distribution of suspended sediment in a cross section(bottle samples combined with acoustic devices).Using correction factors(probe and cross-sectional factor) these monitoring methods are combined and it is,thus,possible to fully document the temporal and spatial variability of the suspended sediment transport and to estimate the suspended sediment load for certain time *** monitoring strategy was implemented at various measurement sites in Austria as well as at the Hainburg Road Bridge site on the Danube *** has already been successfully applied for three years at this measurement site and suspended sediment loads during high discharges up to a 15 year flood event have been *** evaluate the new monitoring methods the results were compared with load estimation methods found in the literature including averaging and ratio estimators as well as rating *** results prove that with the new methodology,the temporal variability of the suspended sediment transport can be detected more accurately compared with the other *** also demonstrate that the additional consideration of the spatial distribution of the suspended sediment concentration in the cross section is crucial as the mean concentration in the cross section can significantly exceed the concentration near the banks,especially at large rivers like the Danube River.

关键词： Suspended sediment Integrated suspended sediment monitoring programme Turbidity sensor Acoustic devices Load estimates

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Experimental investigation on local shear stress and turbulence intensities over a rough non-uniform bed with and without sediment using 2D particle image velocimetry

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International Journal of Sediment Research 2020年第2期35卷 193-202页

作者： Petr Lichtneger Christine Sindelar Johannes Schobesberger Christoph Hauer helmut habersack CD-Laboratory of Sediment Research and Management Institute of Water ManagementHydrology and Hydraulic EngineeringDepartment Water-Atmosphere-EnvironmentUniversity of Natural Resources and Life Sciences

The current work focuses on locally resolving velocities,turbulence,and shear stresses over a rough bed with locally non-uniform character.A nonporous subsurface layer and fixed interfacial sublayer of gravel and sand were water-worked to a nature-like bed form and additionally sealed in a hydraulic ***-dimensional Particle Image Velocimetry(2 D-PIV) was applied in the vertical plane of the experimental flume *** with clear water and weak sediment transport were done under slightly supercritical flow to ensure sediment transport conditions without formation of considerable sediment deposits or *** study design included analyzing the double-averaged flow parameters of the entire measurement domain and investigating the flow development at 14 consecutive vertical *** geometrical variabilities as well the presence of sediment were mainly reflected in the vertical velocity *** the vertical velocity decreased over the entire depth in presence of sediment transport,the streamwise velocity profile was reduced only within the interfacial *** the region with decelerating flow conditions,however,the streamwise velocity profile systematically increased along the entire depth *** increase in the main velocity(reduction of flow resistance)correlated with a decrease of the turbulent shear and main normal ***,effects of rough bed smoothening and drag force reduction were experimentally documented within the interfacial sublayer due to mobile ***,the current study leads to the conclusion that in nonuniform flows the maximum Reynolds stress values are a better predictor for the bed shear stress than the linearly extrapolated Reynolds stress *** is an important finding because,in natural flows,uniform conditions are rare.

关键词： Turbulence measurement Local bed shear stress Sediment transport and flow interaction Hydraulic flume experiment Particle image velocimetry

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Effective transport width——A methodology to describe the spatial variability of bedload transport

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International Journal of Sediment Research 2023年第2期38卷 294-301页

作者： Rolf Rindler Sabrina Schwarz Marcel Liedermann Dorian Shire-Peterlechner Andrea Kreisler Johann Aigner Michael Tritthart helmut habersack Institute of Hydraulic Engineering and River Research Department of Water Atmosphere and Environment University of Natural Resources and Life Sciences

The monitoring of bedload transport processes in rivers is a still challenging task in research and the parameter effective transport width(ETW) allows, for the first time, a process description of the local variability of the bedload transport. In this paper, the distribution of bedload transport over a river crosssection was studied by statistically analyzing long-term monitoring data. Using an innovative integrated measurement system, combining geophones distributed over the river width with bedload traps and basket sampling, allows for continuous, high-resolution, long-term monitoring data of bedload transport characteristics to be generated. Geophone data can be used to record and describe bedload transport processes such as intensity, temporal variability, and local variability. One parameter observed was the ETW, which describes the width where bedload transport is taking place for different discharge classes in gravel bed rivers. With the help of a data series recorded over more than a decade, it is now possible, for the first time, to statistically describe the continuously and directly measured ETW. Hence, it became evident that the effective bedload transport width depends on the discharge rate and local transport capacity, and that bedload transport over the entire river width only occurs at high flows that prevail a few days a year.

关键词： Bedload transport Spatial distribution Effective transport width Plate geophones

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Physical model experiments for sediment supply to the old Rhine through induced bank erosion

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International Journal of Sediment Research 2013年第4期28卷 431-447页

作者： Andres DIE MORAN Kamal EL KADI ABDERREZZAK Erik MOSSELMAN helmut habersack Franck LEBERT Denis AELBRECHT Eric LAPERROUSAZ EDF R&D and Saint-Venant Laboratory for Hydraulics Deltares and Delft University of Technology BOKU University of Natural Resources and Life Sciences EDF-CIH Savoie Technolac

A mobile-bed,undistorted physical model(1:40) has been used to investigate different sediment supply strategies to the Old Rhine through bank protection removal and modifications of groyne dimensions and configuration,which cause bank *** trained channel was previously the main bed of the upper Rhine downstream of Basel(Switzerland),but it has an artificially low flow regime since the construction of the Grand Canal d’Aisace,a navigation canal,and a flow control dam at Kembs(France).Training works and subsequent channel incision have also greatly reduced sediment transport rates and created a heavily armoured *** modelled pilot site has a groyne field on the left *** show that the currently existing groynes at the site are not effective in creating high bank-side velocities conducive to bank erosion,even for flow rates significantly higher than the mean annual How *** river bank has also proved to be more resistant than previously thought,allowing long stretches of bank protection to be safely *** physical model testing process has produced a new configuration for the groyne field,where two higher,larger island groynes are placed further apart than the three existing attached *** innovative approach has proved effective,causing bank erosion for flow rates below the mean annual flow rate,with consistent erosion being *** has also been found that such a configuration does not pose a hazard for the Grand Canal d’Aisace,which is situated next to the Old Rhine,through excessive bank erosion during high flow events.

关键词： Old Rhine Physical model Sediment transport Groyne Bank erosion

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Sediment loads and processes in large rivers

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International Journal of Sediment Research 2013年第4期28卷 429-429页

作者： helmut habersack Daniel HASPEL University of natural resources and life sciences Vienna Institute for water managementHydrology and hydraulic engineering

The pressure and impact on large rivers have increased greatly in recent years,as a consequence of their exploitation to meet various human *** rivers are particularly exposed to problems of multiple uses,often with conflicting *** the global scale river systems are increasingly altered by dams,leading to interruption of continuity and a disrupted sediment regime,which results in far-reaching *** challenges point also to the need for more integrated management approaches and consideration of catchment-river interactions emphasizing land use management and effects of these *** the global scale,there is currently no overview assessment of the current status of the world's large rivers,the conflicting demands on such rivers,and likely future anthropogenic impacts,as well as the potential for restoration,improvements in integrated management and the associated problems caused by their multiple *** special issue in the International Journal of Sediment Research on"Sediment loads and processes in large rivers"aims to provide a global forum for a wide-ranging discussion of key issues related to research on large rivers and to their effective and sustainable management,involving both scientists and decision *** sequence of papers in the special issue highlights the current situation in different river systems with regard to morphodynamic reactions of

关键词： Sediment loads and processes in large rivers

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CATCHMENT-WIDE, SECTIONAL AND LOCAL ASPECTS IN SEDIMENT TRANSPORT MODELLING AND MONITORING

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International Journal of Sediment Research 1997年第3期 120-130页

作者： helmut M.habersack Research Assistant, Institute for Water Management, Hydrology and Hydraulic Engineering, Universitaet fuer Bodenkultur, Muthgasse 18, 1 190 Vienna, Austria

The aim of this paper is to analyse the relevance of different scales for the methods and reliability of sediment transport modelling and monitoring techniques. Both deterministic as well as stochastic approaches allow to derive specific results in different scales whereaby the deterministic, physically based methods are mostly limited to local and sectional aspects. The larger the scale becomes the more stochastic compnents enter the system. At the same time basic features in the larger scales line catchments show a fractal nature and a scale independent behaviour. Throughout the paper a framework for sediment transport modelling and monitoring in different scales is discussed. Starting with catchment-wide analysis using optimal channel network (OCN-) techniques etc. based on digital elevation maps (DEMs) a downscaling process leads to the analysis of local structures like meander-modelling. Based on the point- and local scale an upscaling procedure allows to derive overall conclusions for the catchment and management measures.

关键词： Sediment transport River morphology Geomorphology Scaling

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CATCHMENT-WIDE ANALYSIS OF THE SEDIMENT REGIME WITH RESPECT TO RESERVOIR SEDIMENTATION

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International Journal of Sediment Research 2001年第2期16卷 159-169页

作者： helmut M. habersack1 ,Konrad BOGNER1, Josef SCHNEIDER1 and Michael BRAUNER2 1Department of Water Management, Hydrology and Hydraulic Engineering, University of Agricultural Sciences Vienna, Muthgasse 18, 1190 Vienna, Austria. 2Department of Forest and Department of Water Management Hydrology and Hydraulic Engineering University of Agricultural Sciences Vienna Muthgasse 18 1190 Vienna Austria Department of Forest and Mountain Risk Engineering University of Agricultural Sciences Vienna Pater Jordanstrasse 82 1190 Vienna Austria

The aim of this paper is to discuss a catchment-wide approach for analysing the sediment regime with respect to reservoir sedimentation, based on the Alpine Solk-basin in Austria. On a scaling perspective the boundary conditions and major processes of a catchment, like the geomorphological setting, axe given by longterm developments. On the basis of field mapping these effects are discussed with respect to sediment availability, being affected e.g. by deep-seated gravitational slope deformations and slope creeping. Within these longterm processes, short-term unsteady sediment supply, erosion, transfer, deposition and remobilization processes determine reservoir sedimentation and management. An intensive field monitoring program, including bedload and suspended sediment measurements, supplies data for the subsequent rainfall-runoff-erosion and sediment transport modeling (input, calibration and validation data). Instead of aiming to predict sediment transport processes in a purely deterministic manner the use of stochastic concepts allows to define locations in the catchment with a high probability for delivering significant amounts of sediments to the channels and finally the reservoir. Results show that landuse, channel regulation and avalanches are of great importance for sediment supply and that catchment management (beside managing the reservoir itself) has to address these.

关键词： Reservoir sedimentation Erosion modeling Sediment load Watershed management

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