impact - wp4 dam-break induced floods and sediment movement progress report
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Louvain-la-Neuve -Nov 2003
Dam-break floods and sediment movement
1
IMPACT - WP4IMPACT - WP4
Dam-break inducedDam-break induced floodsfloodsand sediment movementand sediment movement
Progress report
Université catholique de Louvain
Yves Zech, Benoit Spinewine and Nicolas le Grelle
IMPACTInvestigation of extreme flood Processes and uncertainty
Louvain-la-Neuve -Nov 2003
Dam-break floods and sediment movement
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Aims and objectivesAims and objectives
Improve the prediction
of the motion of sediments
in association with catastrophic floods
Louvain-la-Neuve -Nov 2003
Dam-break floods and sediment movement
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Issues of IMPACT WP4 researchIssues of IMPACT WP4 research
• Extreme flows
intense erosion and solid transport
• Intense sediment transport
affects flood-wave prediction– Arrival time– Maximum water level– Morphological changes
Louvain-la-Neuve -Nov 2003
Dam-break floods and sediment movement
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Scope of the researchScope of the research
• Near-field – Uniform debris flow– Severe transient debris flow
• Far-field – Intense transport– Bank erosion and geomorphic changes
Louvain-la-Neuve -Nov 2003
Dam-break floods and sediment movement
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Near field : problems to be solvedNear field : problems to be solved
• Initiation of movement– Acting forces– Vertical effects– Inertial effects– Sediments bulking
• Propagation– Intense scouring– Debris-flow front
Louvain-la-Neuve -Nov 2003
Dam-break floods and sediment movement
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Near-field : programme & scheduleNear-field : programme & schedule
• Debris flow : acting forces (UDT)
• Dam-break experiments (UCL)
• Dam-break numerical modelling (UCL)
• Validation of codes (UDT, UCL, Cem)
Louvain-la-Neuve -Nov 2003
Dam-break floods and sediment movement
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• Debris flow : acting forces (UDT)– Uniform material
• Months 1-18
– Graded material• Months 19-32
Near-field : programme & scheduleNear-field : programme & schedule
Louvain-la-Neuve -Nov 2003
Dam-break floods and sediment movement
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Near-field : programme & scheduleNear-field : programme & schedule
• Dam-break experiments (UCL)– Same bed levels
• Months 1-9
– Initial step in bed level• Months 1-9 > 1-23
BM UCL 1
BM UCL 2
Louvain-la-Neuve -Nov 2003
Dam-break floods and sediment movement
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Near-field : programme & scheduleNear-field : programme & schedule
• Dam-break numerical modelling (UCL)– 1D model : months 1-6
– 2D-V model : months 21-32
Louvain-la-Neuve -Nov 2003
Dam-break floods and sediment movement
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Near-field : programme & scheduleNear-field : programme & schedule
• Validation of codes (UDT, UCL, Cem, IST)– 1D dam-break flow in the near field
BM UCL 1
BM UCL 2
Louvain-la-Neuve -Nov 2003
Dam-break floods and sediment movement
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Far field : problems to be solvedFar field : problems to be solved
• Transition from near-field to far-field• Geomorphic changes
– Bank erosion and failure• Tractive forces applied
• Failure mechanism
– Channel widening
– Deposition of material• De-bulking• Distribution of sediments• Secondary dams
Louvain-la-Neuve -Nov 2003
Dam-break floods and sediment movement
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Far field : programme & scheduleFar field : programme & schedule
• Laboratory experiments– Dam-break in an initially prismatic valley
(UCL)– Large-scale model (Châtelet)
• Field experiments : Norwegian dam (SG)
• Numerical modelling (UCL)
• Validation (UCL, UDT, Cemagref, IST)– Laboratory tests– Field cases
Louvain-la-Neuve -Nov 2003
Dam-break floods and sediment movement
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Far field : programme & scheduleFar field : programme & schedule
• Laboratory experiments– Dam-break in an initially prismatic valley
(UCL)• Uniform material• Graded material >
probably one test
• Months 13-20
BM UCL 4
Louvain-la-Neuve -Nov 2003
Dam-break floods and sediment movement
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Far field : programme & scheduleFar field : programme & schedule
• Laboratory experiments– Large-scale model (Châtelet)
• Months 24-31 > 27-31 • Prismatic valley
– Same bed level (DB)– (Initial step) (DB)– With embankment (BM Chat)
• Enlargement (BM Chat)BM Chat
Louvain-la-Neuve -Nov 2003
Dam-break floods and sediment movement
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Far field : programme & scheduleFar field : programme & schedule
• Field experiments– Norwegian dam (SG)
• Geomorphic survey not realised
• Months 9-12 : cancelled
• Months 19-21:
– Downstream survey (DB)
Louvain-la-Neuve -Nov 2003
Dam-break floods and sediment movement
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Far field : programme & scheduleFar field : programme & schedule
• Numerical modelling– Extension of 2D-H model (UCL)
• Bank erosion
• Months 12-20
> 12-31
50°
37°
85°
Vbank
Louvain-la-Neuve -Nov 2003
Dam-break floods and sediment movement
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Far field : programme & scheduleFar field : programme & schedule
• Validation (UCL, UDT, Cemagref, IST)– Laboratory tests
• Prismatic valley, with embankment
– BM UCL 4 : small scale– BM Chat 1 : large scale
• Enlargement (BM Chat 2)
BM ChatBM UCL 4
Louvain-la-Neuve -Nov 2003
Dam-break floods and sediment movement
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Far field : programme & scheduleFar field : programme & schedule
• Validation (UCL, UDT, Cemagref, IST)– Field cases : Lake Ha!Ha!
• Months 33-35 > 24-34
BM Ha!Ha!
Brooks and Lawrence1999
Louvain-la-Neuve -Nov 2003
Dam-break floods and sediment movement
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Benchmark summaryBenchmark summary
• Near field
• Far field
BM UCL 1BM UCL 2
BM UCL 4
BM Ha!Ha! BM Chat
Louvain-la-Neuve -Nov 2003
Dam-break floods and sediment movement
20
IMPACT - WP4IMPACT - WP4
Dam-break inducedDam-break induced floodsfloodsand sediment movementand sediment movement
Progress report
Université catholique de Louvain
Yves Zech, Benoit Spinewine and Nicolas le Grelle
Louvain-la-Neuve -Nov 2003
Dam-break floods and sediment movement
21
Decisions / questions / discussionDecisions / questions / discussion
• Experiments– Experiments with an initial step
• new flume available in June 2003• completion postponed till September 2003
> November 2003 (1)
– Extension to graded material• for the forces acting on sediment• near-field experiments : a few bimodal
tests• far-field : probably one test
Louvain-la-Neuve -Nov 2003
Dam-break floods and sediment movement
22
Decisions / questions / discussionDecisions / questions / discussion
• Benchmarks– Benchmark BM UCL2 :
Dam break experiment with initial step • benchmark available in November 2003• results December 2003 > March 2004 ?
(2)
– Benchmark BM UCL3 : 2D-V case• cancelled
Louvain-la-Neuve -Nov 2003
Dam-break floods and sediment movement
23
Decisions / questions / discussionDecisions / questions / discussion
• Benchmarks– Benchmark BM UCL4 :
Dam-break flow in initially prismatic valley, with uniform (and graded) material• form of the benchmark : 2003 tests• launched in September > November ? (3)
– Benchmark BM Chat : Large scale dam-break experiments with uniform material (LRH Châtelet)• form of this benchmark ? (4)
Louvain-la-Neuve -Nov 2003
Dam-break floods and sediment movement
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Decisions / questions / discussionDecisions / questions / discussion
• Benchmarks– Benchmark BM Norway :
Norway field test• cancelled ? (5)
– Benchmark BM Ha!Ha! : Lake Ha!Ha! dam-break event• feasibility of the schedule• invite a member of the Geological Survey
of Canada• discuss format > launched at LLN meeting
Louvain-la-Neuve -Nov 2003
Dam-break floods and sediment movement
25
IMPACT - WP4IMPACT - WP4
Dam-break inducedDam-break induced floodsfloodsand sediment movementand sediment movement
Progress report
Université catholique de Louvain
Yves Zech, Benoit Spinewine and Nicolas le Grelle
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