SAFERELNET MeetingAutostrade per l’Italia

Task 2.5 (Risk of Natural Hazards)

Fri. 19th Nov., 17.00-18.00h

Outline

• Who is the public and what do we want to solve?

• Overview partners and their progress

• Appendices– Review of books on natural hazards– Review of ongoing EU projects on floods– Plan for 2005

Main goal of Task 2.5

• Identification and further development of emerging ideas and solutions which hold promise for practical implementation with focus on: Earthquakes, Landslides, Extreme Waves, River Floods.

• Dilemma: should it focus on certain aspects of natural hazards, or should the task be presented as a complete entity which also involves physical, and social realities related with natural hazards?

• Public -> Practicing design engineers, code committees on risk and reliability, but also SAFERELNET partners of the other WPs

Natural Disasters

• Floods & Storms• Landslides • Forest FiresForest Fires• Earthquakes• VolcanoesVolcanoes

Partners in Task 2.5

Focus

• Prof. Stoeva and Farrokh Nadim will investigate the geotechnical stability of land masses and dikes especially in situations of high water

• Carlos Guedes Soares, Angelo Teixeira, Philip Smedley and Gholamhossein Najafian will focus in Task 2.5 on risk assessment models of water related hazards, such as extreme waves and extreme water levels.

• Dan Lungu, Iolanda Craifaleanu, Emil-Sever Georgescu, and Ton Vrouwenvelder will focus in Task 2.5 on Risk Assessment Models of Earthquakes.

• Pieter van Gelder focuses on the integral overview of natural hazards research and river floods in Task 2.5.

General approach

• Risk management of natural hazards needs to include the steps of hazard identification, risk analysis (probability of occurrence- and consequence analysis), risk assessment and risk mitigation (including CBA’s of mitigation strategies)

NGI and UMG

• NGI has reviewed concepts and proposed an overall method for mapping the hazard and risk due to landslides along a pipeline route.

• Susceptibility of a slope to instability depends on the topography, lithology and geotechnical characteristics of the material in the slope, hydrological conditions and ground surface cover.

NGI

• Most common triggering mechanisms for slope instability on land, other than gravity, are rainfall, earthquake and human activity, all of which can at best be modelled as random processes.

• The relative landslide hazard level Hlandslide is determined from:

• Hlandslide = (Sr * Sl * Sh) * (Ts + Tp)• where Sr is the slope factor, Sl is the lithological factor, Sh is the relative soil moisture factor, Ts is the seismic

trigger indicator, and Tp is the precipitation (rainfall) trigger indicator.

Identified emerging topics for further research

• Improvement of Hlandslide

INCERC and TUD

• Seismic hazard assessment is related to

the prediction of the strong ground motion

likely to occur at a particular site and the

subsequent response by the structure. It is

based on the following steps:

Seismic risk assessment

MMI

MR

• Identification and quantification of sources• Attenuation relationship• Ground motion description• Structural response• Consequences

Seismic active areas on the world

Fig. 7.2: Geographic distribution of earthquake epicenters, recorded between

27/11/2001 and 27/11/2002.

Inventory of seismic zones (source areas)

1 0 0

1 0

1

0 . 1

0 . 0 1

1 2 3 4 5 6 7

n u m b e r o f e a r t h q u a k e s N i n z o n e j

m a g n i t u d e M

a r e a : 5 0 , 0 0 0 k m 2 p e r i o d : 1 y e a r

ln )mm(BA)mM(N o

Attenuation

ˆ ( , )ga f M R

M = MagnitudeR = Distance to hypocentreε = Model uncertainty factorâg = Peak ground acceleration

M (magnitude)

source area j

R

ga

site

Return period T = 500 year, Distance R = 50 km

Statistical data: B = 2 , mo = 3, No = 5 earthquakes per year

 MT=500 yr = mo + (1/B)ln (No T) = 3+ 0.5 ln(5*500) = 6.7

Attenuation law according to Donovan (C = 10.8 m/s2, R in km):

= 1.10 m/s2

0.5

1,32( 25)

M

gd

C eâ

R

Example (one source area)

Input:

Unit peak ground acceleration

System: MDOF (Te )

Output:

Maximum relative displacement max(u(t))

Response spectrum approach / MDOF

Nonlinear dynamic analysis is, at present, the most elaborate method available for the assessment of the seismic behaviour of building structures.

INCERC

• INCERC reviewed the theory of inelastic response spectra with assumed hysteretic behaviour of structures in seismic hazard and risk analysis, with examples from studies on this topic performed in Romania

INCERC

• Unlike the case of elastic spectra, the applications of inelastic spectra are today relatively unfamiliar to many practising design engineers. These applications, until recently situated primarily in the fields of research and of development of code provisions, are now penetrating in those of the new, performance based, structural design methodologies.

Identified emerging topics for further research

• soil structure interaction

• change of natural frequencies in case of plasticity

• peak ground acceleration as basis for design

PAFA, UNIVLIV and IST

• Risk of extreme wave heights caused by extreme winds

Design guidance for FPSOs

• The development design guidance for Floating Production, Storage and Offloading (FPSO) vessels subject to green water loading requires:

• The characterisation of the long-term likelihood and severity of green water events.

• The calculation of the probability of green water loading requires data relating to both the sea conditions and the vessel characteristics.

• The relevant vessel characteristics include the vessel dimensions, the relative motion response amplitude operators (RAOs) and

• The operational procedures.

PAFA, IST and UNIVLIV

• The design guidance that has been developed has sought to address perceived deficiencies in current Classification Society Rules.

Identified emerging topics for further research

• RFA of extreme wave heights

• Satellite data interpretation

• Freak waves explanation with physical models

• Bow shape design optimisation for FPSOs

TUD

• Risk of river floods caused by extreme precipitation (and failure of flood defences)

Elbe Flood 2002Elbe Flood 2002

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affected cities#

flooded river

damage area

HUNGARY

SLOVAKIA

CZECH REPUBLIC

AUSTRIA

GERMANY

ViennaRosenheim

Passau

Regensburg

Salzburg

Linz

Prague

Krems

LeipzigBitterfeld

DessauMagdeburg

Dresden

Pilsen

© 2004

Geo Risks Research Dept.,

Munich Re

Summer floods 2002:Summer floods 2002:affected regionsaffected regions

103,00

105,00

107,00

109,00

111,00

113,00

01.0

7.0

2

01.0

8.0

2

01.0

9.0

2

01.1

0.0

2

01.1

1.0

2

01.1

2.0

2

01.0

1.0

3 groundwater

Elbe river

9,70 m

Damages by the flood:• 9,2 billion € F.R.G.• 6,1 billion € Saxonia• 0,9 billion € Dresden

Main problems in Dresden

• damages in the city by surface water

• damages to buildings by increased groundwater

Number of Floods worldwideNumber of Floods worldwide

Source: Dartmouth Flood Observatory, 2003

Regional Distribution of Large FloodsRegional Distribution of Large Floods

Source: Dartmouth Flood Observatory, 2003

1999-2002

1985-1988

Reasons for ConcernReasons for Concern

Source: Smith et al 2001, TAR IPCC WG II

DRILLING CORE FROM GREENLAND:DRILLING CORE FROM GREENLAND:Climate History of the last 100 000 YearsClimate History of the last 100 000 Years

Source: Ice Core Project, 2004

Climate changes in the past (not caused by human influence)

Eem

Trends in river discharges?

1900 1920 1940 1960 1980 20001000

1500

2000

2500

3000

3500Annual Average River Discharge Data at Lobith, Rhine

100

101

102

103

0

2

4

6

8

10

12

14x 10

5

Time [yr]

Sp

ect

ral D

ens

ity

Lobith Annual Average

100

101

102

103

0

1000

2000

3000

4000

5000

6000

7000

8000

Time [yr]

Sp

ect

ral D

ens

ity

Vlotho Annual Average Discharges

100

101

102

103

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2x 10

4

Time [yr]

Sp

ect

ral D

ens

ity

Borgharen Annual Average Discharges

100

101

102

103

0

1

2

3

4

5

6

7

8x 10

5

Time [yr]

Spe

ctra

l De

nsity

Koeln Annual Average Discharges

Periodic components

• River discharges (AM): 4.2 years– Van Gelder, Kuzmin, and Visser (2000)

• Global temperature records: 20 months– Tsonis et al. (1998)

• Hurricane activity in North-Atlantic: near decadal– Elsner et al. (1999)

year

dese

ason

alis

ed d

aily

mea

n ru

n-of

f

Daily Mean Run-Off Anomalies at Daily Mean Run-Off Anomalies at Achleiten Danube RiverAchleiten Danube River

POT

I Methods: Statistical methodsI Methods: Statistical methodsProblems:•find suitable distribution that fits your measured data•estimate suitable parameters for the distribution function

Common approach:Gumbel, Frechet, Weibull Distributions (limit distributions of GEV)

unified to the:Generalized Extreme Value Distribution (GEV, 1943)

Further: GPD: Generalized Pareto Distribution (Poisson) POT

GEV: PDF & QuantilesGEV: PDF & Quantiles

Fat tails

II Methods: AssumptionsII Methods: Assumptions

Data must be identically and

independently distributed (IID)!

This neglects:• Internal correlation (seasonality, long-range, etc.)• Stationarity is a prerequisite• Model variation (suitability of GPD/POT)

Typical Techniques and SolutionsTypical Techniques and Solutions

• Guarantee statistical independence, e.g. by elimination of correlation, e.g. seasonality

• Devide the data k subsets, choose highest value and assume that these are independent (GEV-max/GDP-pot)

• Separate trends and variability• Stochastic modelling to examine the

internal structure

Identified emerging topics for further research

• Connecting statistical models with physical models

• Explanation of periodic components in environmetric data

• Better consequence models (evacuation models for people)

Appendices

• Review of books

• Review of ongoing EU projects on floods

• Table of contents of 2003 proceedings, 2004 proceedings

• Plan for 2005

Ongoing EU projects on Flood Risks

• EFFS: A European Flood Forecasting System– to develop a prototype of a European flood

forecasting system for 4-10 days in advance, which could provide daily information on potential floods for large rivers, and flash floods in small basins.

• SPHERE: Systematic, Palaeoflood and Historical data for the improvement of flood Risk Estimation– to develop a new approach which complements

hydrologic modelling and the application of historical and paleoflood hydrology to increase the temporal framework of the largest floods over time spans from decades to millennia; in order to improve extreme flood occurrences.

• THARMIT: Torrent Hazard Control in the European Alps– to develop practical tools and methodologies for

hazard assessment, prevention and mitigation, and to devise methods for saving and monitoring potentially dangerous areas.

• CARPE DIEM: Critical assessment of Available Radar Precipitation Estimation techniques and Development of Innovative approaches for Environmental Management. – to improve real-time estimation of radar rainfall fields

for flood forecasting, by coupling multi-parameter polarisation radar data and NWP, and exploiting NWP results in order to improve the interpretation of radar observations.

• IMPACT: Investigation of Extreme Flood Processes and Uncertainty– to investigate extreme flood and defense failure

processes, their risk and uncertainty. Will consider dam breach formation, sediment movement, flood propagation and predictive models, within an overall framework of flood risk management.

• GLACIORISK: Survey and Prevention of Extreme Glaciological Hazards in European Mountainous Regions– to develop scientific studies for detection, survey and

prevention of glacial disasters in order to save lives and reduce damages.

• MITCH: Mitigation of Climate Induced Hazards– A CA dealing with the mitigation of natural hazards

with a meteorological cause, in order to assist planning and management. The main focus will be on flood forecasting and warning, but it will also include other flood related hazards, such as landslips and debris flow, and longer term climate hazards, such as drought, and the possible impact of climate change on the frequency and magnitude hazards

• ADC-RBM: Advanced Study Course in River Basin Modelling for Flood Risk Mitigation - June 2002

• FLOODMAN: Near real-time flood forecasting, warning and management system based on satellite radar images, hydrological and hydraulic models and in-situ data– near real-time monitoring of flood extent using

spaceborne SAR, optical data & in-situ measurements, hydrological and hydraulic model data. The result will be an expert decision system for monitoring, management and forecast of floods in selected areas in Europe. The monitoring will also be used to update the hydrological/hydraulic models and thereby improving the quality of flood forecasts.

• FLOODSITE: The FLOODsite project covers the physical, environmental, ecological and socio-economic aspects of floods from rivers, estuaries and the sea. The project is arranged into seven themes covering:

• Risk analysis – hazard sources, pathways and vulnerability of receptors.

• Risk management – pre-flood measures and flood emergency management.

• Technological integration – decision support and uncertainty.• Pilot applications – for river, estuary and coastal sites.• Training and knowledge uptake – guidance for professionals,

public information and educational material.• Networking, review and assessment.• Co-ordination and management.

The proposed research approach

in FORELANDS

Assessment of Research on Natural Hazards

by Gilbert White, J. Eugene Haas

Natural Hazards and Environmental Change (Key

Issues in Environmental Change) by Bill McGuire, et al

Natural Disasters by David Alexander

Natural Hazards by Edward Bryant

At Risk: Natural Hazards, People's Vulnerability

, and Disasters by Piers M. Blaikie, et al

Estimating Probabilities of Extreme Floods: Methods and Recommended Research by National Research Council

Published contributions of 2003 report

Received contributions for 2004 report• APPLICATIONS OF NONLINEAR MODELS IN SEI

SMIC HAZARD AND RISK ANALYSIS; A STATE-OF-THE-ART FOR ROMANIA by Lungu D, Craifaleanu I.

• Rheologic stability of a clay rock mass by Prof. Stoeva.

• Extreme Wave Effects on Offshore Structures by E.J. Ballard and A.J. Fyfe, PAFA Consulting Engineers

• Mapping of landslide hazard and risk along the pipeline route by Farrokh Nadim and Suzanne Lacasse

• Seismic hazards and current practice by Ton Vrouwenvelder and Halil Karadeniz

• Freak waves by Carlos Guedes Soares

Plan for 2005

• The plan for 2005 is to continue the identification and further development of emerging ideas and solutions which hold promise for practical implementation with focus on: Earthquakes, Landslides, Extreme Waves, River Floods.