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MMtodos para la estimacitodos para la estimacin de n de sedimentossedimentos
ALPS
JURA
FLAT L
AND
Europakarte
Densidad de la Populacion Suiza Densidad de la Populacion Suiza
populacion densa Uso del suelo: conflicto entre la natura y la actividad humana
Hace pocos anos: elaboracion de mapas de riesgo
estimacion del arrastre de fondo= una herramienta importante para la elaboracion de mapas de riesgo y la planificacion del ordenamiento territorial tanto como para la planificacion y construccion de medidas de proteccion
2 metodos para la estimation del aporte de sedimentos en cuencas alpinas
Como determinar Como determinar el aporte de los el aporte de los
sedimentos?sedimentos?
Estimacin del Transporte de Sedimentos a travs de Depsitos
Estimation of sediment transport by sediment retention Estimation of sediment transport by sediment retention reservoirsreservoirs
por una red depor una red demedicionmedicion
Por la calculacion a travez de formulasPor la calculacion a travez de formulas
??
Dos metodologias para Dos metodologias para la estimacion la estimacion ..
project
development
Estimated Process
Estimated bed load
Lehmann Gertsch
PH D Thesis 1993
80 torrents, 1987-1992
Sediment transport
Bed load balancesTotal Bed load charge
Return period100 years
PH D Thesis 2009
58 events , 1987-2005
Debris flows
Bed load balancesTotal Bed load charge
Return period>100 years
Metodologia
Metodologia Lehmann
A Handbook with description of the method is available
Erosion + Transport
Accumulation ?
Retention Basin planned
Sediment yield? Scenarios?
Procedure to assess sediment yield in mountain streams
Procedimiento de la Estimacin del Aporte de Sedimentos en Torrentes
Preparations
Collect data
Study and interpret data
First evaluation of mountain stream
Collection and processing ofdischarge information
Field Work
Assign mountain stream to a category:- no debris flow stream- debris flow stream with deposits- debris flow stream without deposits
Record parameters applicable tocategory
Analysis
Calculation of sediment yield at the conefor the corresponding category
Plausibility check and sensitivityanalysis
Check results of prepartion work againstfield conditions
Assessment in the field
Alta relevancia Relevancia posibleRelevancia probable
Deslizamiento
Transporte enBarranca
Flujo de Lodo
Falla de la Escarpa
Transporteen el Ri
Fuente Fuente de erosion?de erosion?
Cual de los Cual de los procesos es procesos es relevante ?relevante ?
Calculo con formulaCalculo con formulaT
ran
spo
rtkapa
zitt
gross
klein
Bannwald
Pendiente
?? Dimensiones?
Aporte lateral: Deslizamientos
?espesor
longuitud
Ejemplos para la estimacion de los volumenes
Propuestas para cada tipo de fuente
de sedimentos
Procedure:Determination of sediment balance for each channel section
Level of operation: Handbook Theory book Computer program for calculation
Procedimiento: Determinacin de la Erosin y de la Acumulacin para cada seccin del Torrente
Herramientas para el Procedimiento: Manual Libro Especializado Programa de Computacin
Assessment of sediment yield in mountain streams
Estimacin del Aporte de Sedimentos en Torrentes
...por tramos...
Estimation of sediment transport in small mountain streamsResultado de la Estimacin del Transporte de
Sedimentos en el Torrente Guppenruns
Sediment transport during a 100-year flood in the Guppenruns
Cross section Nr.
V
o
l
u
m
e
Transport capacitySediment yield
Sediment potentialDeposits
740
760
780
800
820
840
860
880
900
920
940
0
5000
10000
15000
20000
250007
2
5
6
7
4
5
6
7
6
5
6
7
8
5
6
7
9
9
6
8
1
5
6
8
3
5
6
8
5
5
6
8
7
5
6
8
9
5
6
/
2
4 6 8
1
0
1
2
1
4
1
6
1
8
2
0
2
2
2
4
2
6
2
8
3
0
3
2
3
4
3
6
3
8
4
0
4
2
4
4
4
5
a
4
6
a
4
8
5
0
5
2
F
e
s
t
s
t
o
f
f
f
r
a
c
h
t
(
m
3
)
Nr. der Querprofile
Scenarios with a short and long rainfall input with a river bed widening
Bornige BrckeMdg. Trmmelbach
Mattebach
Sefinenltschin
untere --- obere Stechelbergbrcke
change of bed levelBornige Brcke
Mdg. Trmmelbach
Mattebach
Sefinenltschi
untere --- obere Stechelbergbrcke
Q = 83 m3/s Q = 57 m3/s
Lange Ganglinie
Metodologia Gertsch
Assessment of hillslope processes
Assessment of channel processes
Bed load balances in all channel parts in dependance from scenario
Total bed load at fan apex
Composition of data Digital data, and field data
Scenario definition qualitative, descriptive
With the aid of developped assessment matrixes for hillslopes and channel automated programme
Delineation of channel parts and adjoining slope parts
Possible with GIS
Extraction of input parameters
Combined impact of all influence factors Combined impact of all
influence factors is essential for bed load mobilisation
Every channel part is influenced by a unique and individual combination of influence-factors
Combined impact = complex
During the combined impact, the different influence-factors can: cumulate each other
compete against each other eleminate each other I
Influence-factor do not have the same weight in each situation
Understanding system element studying channel part
Channel part to be assessed
perspective
Influence factors system element-level
local disposition
Bed load supplyEdisriederbach, Sachseln
rock
Leimbach, Frutigen
limited
Milibach, Meiringen
unlimited
Local disposition
Torrent de Sax, Fully
steep erosion flat deposition
Rio de Tennasses, Chteau-dOex
Channel gradient
Local disposition
Channel part to be assessed
perspective
Interaction between system elements studying channel parts upstream
conditions upstream
Influence factors interaction-level
Runoff supply / catchment area aboveLes Creusats, Orsires
Local disposition
Channel part to be assessed
perspective
flip-over-effects in the system looking for critical constallations or processes
negative factors
special conditions or processes
release of extreme debris flows
extreme erosion rates from release point untill fan apex flip-over-effect
erosion rates > 30 m3/m
Influence factors flip-over-level
Release of debris flows in bastion-moraines Rotlauibach, Guttannen (Foto: Flotron AG)
Confluence of several channels at the same locationRotlauibach, Guttannen (Foto: Flotron AG)
Assessment criteria Decision-making support Assessment and quantification
Local disposition
Transport process
Repressing and increasing factors for
erosion
influence-factor-combination
Assessment line
Quantification
* 400m = 1600m3
* 200m = 8000m3
* 800m = 0m3
* 130m = 11700m3
Simulacion Evento 2004 (oleaje)
Total = 21000 m3
4m3/m40m3/m0m3/m
90m3/m
* 400m = 1600m3
* 200m = 2000m3
* 800m = 0m3
* 130m = 2210m3
Scenario Flujo de escombros
Total = 6000 m3
4m3/m10m3/m0m3/m
17m3/m
Scenario Bed load transport without release of debris flow
Total = 1720 m3
* 400m = 800m3
* 200m = 400m3
* 800m = 0m3
* 130m = 520m3
2m3/m2m3/m0m3/m
4m3/m
Estimated Process
Estimated bed loadReturn period
Necessary time for application for a unit of 5km2-catchment
ScaleChannel gradient
Methode Lehmann Methode Gertsch
Sediment transport
Bed load balancesTotal Bed load charge
Return period100 years
3 days
< 50 km2
> 2%
Debris flows
Bed load balancesTotal Bed load charge
Return period>100 years
2 days
< 10 km2
> 10%
Comparacion final
Gracias por su atencion!!!!!