ÉCOLE POLY TECHNIQUEFÉDÉRALE DE LAUSANNE

L M R - L M SLABORATOIRES DE

MÉCANIQUE DES ROCHES ET DES SOLS

Dr. Vincent Labiouse Prof. Lyesse Laloui

Contribution to the Mountain-Risks projectof the

Rock and Soil Mechanics Laboratoriesof the

Swiss Federal Institute of Technology Lausanne

2

EPFL LMR - LMS

EPFL - Rock and Soil Mechanics Laboratories

g Presentation of the laboratoriesn Main activitiesn LMR research : Rock falls and Cliff instabilitiesn LMS research : Hydro-mechanical modelling of landslides

g Contributions to the Mountain-Risks projectn Early-Stage Researcher ESR 8n Experienced Researcher ER 3n Network-wide training activities

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EPFL LMR - LMS

EPFL - Rock and Soil Mechanics Laboratories

About 35 people providingn Research and development

4 Mechanics of multiphase porous media4 Geomechanics and energy4 Management and modelling of natural hazards4 Mechanical behaviour of rocks and rock masses4 Design and technology in tunnelling and underground constructions

n Teaching and training4 Soil and Rock Mechanics4 Geotechnical and tunnelling engineering4 Natural Hazards

n Service and consultancy4 Soil and rock testing accredited according to the ISO/CEI 17025 Standard

LMS

LMR

4

EPFL LMR - LMS

Experimental study of block bouncing (FNS, PhD 2004)

Hazard mapping of rock instabilities (Vaud, 2002)

Run-out of fragmental rock blocks (Interreg IIC, 2002)

Design of protection galleries (FNS, PhD thesis 1998)

Run-out of rock avalanches (Interreg IIIA, 2006, PhD)

Rock falls and Cliff instabilities

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EPFL LMR - LMS

Hydro-mechanical modelling of landslidesAdvanced constitutive modelling of unsaturated soils

- Improved modelling of mechanical behaviourunder various saturations

- Single mechanical effective stress

Matricsuction s

Degree of saturation Sr

Voidratio e

Double-wayH-M coupling

Hydraulic part :Advanced SWCC description

ACMEG-s : Advanced Constitutive Model for Environmental Geomechanics

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EPFL LMR - LMS

Advanced three-phase FE modelling

Prediction of the time-dependent behaviour of the Triesenberglandslide (Liechtenstein)

Stabilisation of La Frasselandslide (Canton of Vaud)

unsaturated zone(s=pa-pw)

deg. of saturation Sw

runoff

groundwater level(pw=0)

saturated zone1 0

1890 m43

3 m

406.3 kN/m

Hydro-mechanical modelling of landslidesFinite elements modelling of landslides

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EPFL LMR - LMS

EPFL - Rock and Soil Mechanics Laboratories

g Presentation of the laboratoriesn Main activitiesn LMR research : Rock falls and Cliff instabilitiesn LMS research : Hydro-mechanical modelling of landslides

g Contributions to the Mountain-Risks projectn Early-Stage Researcher ESR 8n Experienced Researcher ER 3n Network-wide training activities

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EPFL LMR - LMS

Background of the ESR 8 position : CADANAV hazard mapping methodology elaborated at LMR

N

500 m

g Approach consistent with the Swiss federal guidelinesn Rough delineation at regional and valley scales of the areas at

risk to detect conflicts with land use preliminary mapsn Detailed hazard assessment at local scale, accounting for the

magnitude and mean return period of events hazard maps

Preliminary map at regional scale

Preliminary map at valley scale

Hazard map at local scale

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EPFL LMR - LMS

ESR8

g Points to be tackled :n to collect information on present methodologies in Europe, with a

particular emphasis on those that could be used with GIS;n to work out procedures at regional scale for a first rough delineation

of the areas at risk, and at local scale for a more detailed assessment of rockfall hazard;

n to develop a methodology that takes into account the temporal probability and volume of the events as well as the spatial extent and velocity of the rock falls;

n to evaluate the influence on land-use planning and risk of different factors and scenarios, like the increase in frequency and/or magnitude of hazardous events due to either natural (climate) or human-induced changes

Improved methodologies for rockfall hazard and risk mapping at regional and local scales

Rem: The scope of ESR 7 (UPC) and 8 positions should be well defined to avoid a too important overlap of the researches

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EPFL LMR - LMS

Framework of the ESR 8 position

g Host institutes and supervisorsn Principal : LMR-EPFL (Labiouse)n Secondment : Eurogeotècnica (Amigo) and UJF (Jongmans)

g Period : 6 36 monthsg Main contribution to the WB1: Hazard analysis

n TA-01: Develop and harmonise procedures for the identification, location and quantification of the processes creating mountain risk;

n TA-02: Improve the prediction of the spatial extent and the velocity of extreme phenomena (runout distances and impact velocities);

n TA-04: Develop techniques for assessing the temporal probability and the magnitude of the events, determine and map the hazard and validate these outputs

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EPFL LMR - LMS

Background of the ER 3 position :Finite elements modelling of the behaviour of landslides

n Natural slopes represent complex phenomena to model, both in space and time

n Strong need for numerical analysisn Multiphase coupled formulation and

unsaturated soil mechanics may significantly improve the modelling

n Modern 3D FEM analysis is confirmed to be a useful tool for the design and selection of risk mitigation strategies

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EPFL LMR - LMS

ER 3

g Contribution, using hydro-mechanical finite elements approach, to :n the identification of critical factors involved in the behaviour of large

landslides processes (TA-03);n the quantification and mapping of the hazard (TA-04);n the definition of criteria for establishing monitoring networks for

early warning (TA-05);n the development of alert thresholds (TA-13)

g Host institutes and supervisorsn First year in Lausanne at LMS-EPFL (Laloui)n Second year in Barcelona at UPC (Corominas/Ledesma)

g Period : 0 24 months

Hydro-mechanical modellingfor large landslides during crises

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EPFL LMR - LMS

EPFL contribution tothe network-wide training activities

g Topical workshop 2n Single Hazard Analysis (slide, rockfall, debris flow, snow avalanches)n Organisers : LMR-EPFL and Quanterra (CH), Utrecht U and ITC (NL) n Location : Lausanne or Sionn 3 days in autumn 2007 (November)

g Intensive Coursen Multi-scale hazard assessment and riskn Organisers : LMR-EPFL and Quanterra (CH),n Location : Canton of Wallis and/or Vaud, Switzerlandn 5 days in spring 2009

+ First annual meeting of the consortium host in Lausanne (Nov 2007)

ÉCOLE POLY TECHNIQUEFÉDÉRALE DE LAUSANNE

L M R - L M SLABORATOIRES DE

MÉCANIQUE DES ROCHES ET DES SOLS

Dr. Vincent Labiouse Prof. Lyesse Laloui

Contribution to the Mountain-Risks projectof the

Rock and Soil Mechanics Laboratoriesof the

Swiss Federal Institute of Technology Lausanne