IMPACT ~ Breach Formation (WP2)

Overview(4th IMPACT WS)

Breach Formation The Problem to be Solved - AIMSProblem to solve:

• The reliable prediction of breach formation (and hence potential:

– flood hydrograph / flood risk

– breach size

• Approach to identifying potential breach location

Breach Formation The Approach

The overall approach entails combining large scale field work, lab work and numerical model development / application.

5-6m embankments

1:10 scale embankments

Multi-partner

Multi-model

Field Modelling

Lab Modelling

Numerical Modelling

Desk / Data Analysis for Breach Location

Breach Formation Work ProgrammeYear 1:

• 2 x 6m field tests in Norway

• 9 x 0.6m lab tests at Wallingford

• Widen numerical modelling team and integrate modelling programme with field and lab

10:25

11:27

12:23

13:05

Breach Formation Work ProgrammeYear 2:

• 3 x 6m field tests in Norway

• 13 x 0.6m lab tests at Wallingford

• Numerical modelling integrates with field and lab modelling

• Initiate breach location work (factors and methodology)

Breach Formation Work ProgrammeYear 3:

• Finalising numerical modelling comparisons

• Breach location (factors and methodology)

• Application to combined risk assessment / uncertainty

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0 1000 2000 3000 4000 5000 6000 7000 8000Time (sec)

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Outflow clayInflow clayOutflow moraineInflow moraineBreach Top Width clayBreach Top Width moraine

Breach Formation Direction of work:Analysis of this data permits:

• Consideration of scaling differences between field and lab data

• Comparison of controlled test results against observed field data

• Objective performance assessment of multiple numerical models predicting breach formation

• Base data for validation and model development

Breach Formation Deliverables (Overview)Deliverables:

• Field and lab data on breach formation– different geometries & materials

• Comparison and development of breach models• various partner models

• model interface for direct comparison

• commercial products

• Approach for identifying potential breach location

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