Measurement and analysis of the drag coefficient of wood accumulations at an ogee crested spillway

Journal of Hydrology, Journal Year: 2024, Volume and Issue: 631, P. 130798 - 130798

Published: Jan. 29, 2024

Language: Английский

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Working with wood in rivers in the Western United States

River Research and Applications, Journal Year: 2024, Volume and Issue: 40(8), P. 1626 - 1641

Published: June 18, 2024

Abstract Recognition of the important physical and ecological roles played by large wood in channels on floodplains has grown substantially during recent decades. Although continues to be routinely removed from many river corridors worldwide, practice reintroduction spread across United States, Kingdom western Europe, Australia, New Zealand. The state‐of‐science regarding working with rivers was discussed a workshop held Colorado, USA, September 2022 40 participants who are scientists practitioners UK, Japan. objectives this paper present findings workshop; summarize two case studies restoration States; provide suggestions for advancing management. We results based participant judgements recommendations respect to: (i) limitations key barriers using wood, which reflect perceptions practicalities; (ii) gaps use management; (iii) scenarios is generally used effectively; (iv) not effectively. illustrate importance local geomorphic context, configuration complexity potential modification corridor morphology enhance desired benefits. Moving forward, we stress collaboration disciplines communities research scientists, practitioners, regulators, stakeholders; accounting stakeholder wood; increasing non‐scientist access latest knowledge.

Language: Английский

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Towards a non-intrusive method employing digital twin models for the assessment of complex large wood accumulations in fluvial environments

Journal of Hydrology, Journal Year: 2022, Volume and Issue: 614, P. 128505 - 128505

Published: Oct. 5, 2022

Quantification and assessment of large wood (LW) accumulations in fluvial systems is still considered difficult due to the complex nature wooden deposits. Although knowledge about volumetric measures porosity parameters LW crucial for prediction hydraulic geomorphic effects, it has not yet been possible obtain accurate measurements. These limitations are mainly based on a lack applicable sensing technologies available past. In present study, close-range aerial surveying technique (Structure from Motion (SfM) photogrammetry) applied generating 3D replicates (digital twin models) deposits, enabling their assessment. addition, manually conducted measurements corresponding prototype help improve calibrate SfM-derived estimates. For first time, precise accumulations, ranging 52.5 83.2%, provided. novel parameter – packing arrangement used, which describes structural alignment individual elements accumulation benefits estimates 2.5D photogrammetric approach. Accordingly, randomly loosely organised allow high penetration depth approach, resulting more estimate actual porosity, as approaches solid volume accumulation. An empirical approach developed future approximation without need knowing volume. With work significant improvement our understanding employing non-intrusive provided, linked with field accumulations. Our study contributes an improved data acquisition processing plan, represents further important step towards systematic framework that urgently needed by river managers engineers better evaluate manage systems.

Language: Английский

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Remote sensing of laboratory rivers

Earth Surface Processes and Landforms, Journal Year: 2023, Volume and Issue: 49(1), P. 58 - 81

Published: March 18, 2023

Abstract Remote sensing enables us to measure fluvial systems without disrupting their dynamics. Small‐scale physical models of rivers allow observe geomorphic evolution, but we need remote methods monitor these laboratory landscapes altering flow or topography, just as with field‐scale rivers. In this paper, review how experimental geomorphologists have adapted for the laboratory. We consider model depth, velocity and planform been employed, enabling uninterrupted evolution. also explore transfer techniques between sensing; controlled conditions in lab aided development some methods, while others benefited from airborne deployment. recent developments offered by sensing, including through‐water laser scanning adaptations structure‐from‐motion photogrammetry; new challenges associated developments, such computational power. Finally, discuss research problems that is opening up geomorphology. hope will be useful experimentalists seeking collect data remotely, continuously and/or cost‐effectively.

Language: Английский

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Self-Cleaning Ability of the Piano Key Weir with Driftwood Blockages

Journal of Hydraulic Engineering, Journal Year: 2024, Volume and Issue: 150(4)

Published: May 14, 2024

The piano key weir has been successfully used to address discharge deficiencies and site limitations for run-of-river structures new existing spillways, serving as an economical alternative traditional weirs. In addition upstream sedimentation, weirs may also be exposed floating driftwood mobilized by hydrologic events. Driftwood accumulation immediately of or on a crest can decrease hydraulic performance, potentially increasing flooding altering hydrodynamic forces the that cause structural foundational concerns. It is unclear if might influence sediment self-cleaning characteristics Thus, this study physical experiments systematically investigate ability Type A with in setting. simulated substrate was alluvial sand bed naturally shaped. Experiments included combinations different volumes. Results indicate accumulations have significant flow field positively affect sediment. For conditions considered herein, cleaning capacity function volume, surface area its extent reach, discharge. Higher rates increased volume extended scour, resulting higher transport without causing backwater increase water elevation. With sufficient depths at weir, would anticipated pass downstream. Based results, remove adjacent noncohesive deposits.

Language: Английский

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The influence of large wood on sediment routing and flow characteristics: A study in a low-order stream in the southern brazilian plateau

Geomorphology, Journal Year: 2024, Volume and Issue: 465, P. 109398 - 109398

Published: Aug. 25, 2024

Language: Английский

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Effects of logjams on river hydrodynamics under inundation conditions

Journal of Hydrodynamics, Journal Year: 2024, Volume and Issue: 36(4), P. 757 - 771

Published: Aug. 1, 2024

Language: Английский

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SmartWood: field-based analysis of large wood movement dynamics using inertial measurement units (IMUs)

Environmental Sciences Europe, Journal Year: 2024, Volume and Issue: 36(1)

Published: May 7, 2024

Abstract Wood plays an important ecological role in rivers. Yet challenges arise when large wood (LW) is mobilised and transported during floods. Due to a lack of quantitative data, movement behaviour LW floods still not well understood date. A proof-of-concept study was conducted at three Swiss rivers test state-of-the-art sensor-tagged logs, so-called “SmartWood” collect field-scale data about behaviour. The experiments utilised innovative inertial measurement units (IMUs), which have been developed the Laboratory Hydraulics, Hydrology Glaciology (VAW) ETH Zurich implanted into logs (SmartWood) prototype scale. Each IMU comprised individual sensors (gyroscope, accelerometer, magnetometer) equipped with on-board processor, AA battery (4.35 V), memory (8 MB), Wi-Fi transmitter (100 m) for transfer. After successful initial verification tests sensors, IMUs were installed debranched measuring 4.35 m length 0.33 diameter. At time field experiments, each SmartWood-log weighted between 170 220 kg, yielding density roughly 500 kg∙m −3 . Limmat, Thur, Grosse Melchaa Rivers Switzerland, yet discontinuous obtained. Results revealed consistent dynamics across all sites. Specifically, we observed positive yaw transport SmartWood along left river bank negative right bank. Furthermore, interactions channel boundaries, riparian vegetation, objects (e.g., ferry dock) registered quantified, even out sight traditional sensing methods. enabled testing exposed critical limitations software algorithms reconstruction analysis floating dynamics. gained knowledge introduced method will benefit assessment maintain safety functionality instream structures considering robust design retention guiding structures), but also restoration projects numerical models that rely on data.

Language: Английский

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A conceptual model on the influence of logjam formation on longitudinal and lateral sediment dynamics in forested streams

Geomorphology, Journal Year: 2024, Volume and Issue: 458, P. 109260 - 109260

Published: May 17, 2024

Language: Английский

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