1. No category

Identification and mapping
of the Valići Lake Landslide
(Primorsko-Goranska County,
Croatia)
Snježana MIHALIĆ ARBANAS
Sanja BERNAT
Marin SEČANJ
Martin KRKAČ
Faculty of Mining, Geology and Petroleum Engineering, University of Zagreb
Željko ARBANAS
Faculty of Civil Engineering, University of Rijeka
CLG
2nd REGIONAL SYMPOSIUM ON
LANDSLIDES IN THE ADRIATIC-BALKAN
REGION
BELGRADE, SERBIA, 14-15 May 2015
Croatia
Europe
Valići Lake Landslide
Rječina River Basin
(Primorsko-Goranska County)
CLG
2nd REGIONAL SYMPOSIUM ON LANDSLIDES IN THE ADRIATIC-BALKAN REGION
BELGRADE, SERBIA, 14-15 May 2015
Valići Lake Landslide
•
Landslide activation and
urgent measures
•
Landslide identification and
mapping
•
Landslide modeling
Wider area
• Hazard and risk
assessment in the Rječina
River basin
CLG
2nd REGIONAL SYMPOSIUM ON LANDSLIDES IN THE ADRIATIC-BALKAN REGION
BELGRADE, SERBIA, 14-15 May 2015
LANDSLIDE ACTIVATION AND URGENT
MEASURES
Valići Lake Landslide
after activation in February 2014
Valići Lake Landslide
Landslide activation phases in 2014
Before
Feb 2014
Continuous
road damaging
by creeping and
road reparation
woks
CLG
Development of
shear cracks on
the road
6 Feb
2014
7 Feb
2014
Closure of
traffic
Landslide
collapse
(before 2 pm)
13 Feb
2014
2nd REGIONAL SYMPOSIUM ON LANDSLIDES IN THE ADRIATIC-BALKAN REGION
BELGRADE, SERBIA, 14-15 May 2015
Valići Lake Landslide
Urgent measures after landslide collapse
BASE FOR HAZARD MODELING
related to risk for reservoir lake,
dam and indirect losses
LANDSLIDE MAPPING
CLG
2nd REGIONAL SYMPOSIUM ON LANDSLIDES IN THE ADRIATIC-BALKAN REGION
BELGRADE, SERBIA, 14-15 May 2015
Valići Lake Landslide
Geomorphological mapping
LOCAL ROAD
ACTIVATED LANDSLIDE
VALIĆI DAM RESERVOIR
VALIĆI DAM
RJEČINA RIVER
Valići Lake Landslide
Geomorphological mapping
Problems
•
•
Availability of detailed topographic base map (in short time)
Forest vegetation cover
Solutions
•
High resolution bare-earth DEM (1-m resolution) derived by LIDAR
scanning in 2011
CLG
2nd REGIONAL SYMPOSIUM ON LANDSLIDES IN THE ADRIATIC-BALKAN REGION
BELGRADE, SERBIA, 14-15 May 2015
Valići Lake Landslide
Phases of landslide identification and
mapping
Interpretation
of DEM derivative
maps
CLG
Ground survey
and
field mapping
Landslide cross
section
interpretation
and
slope stability
analysis
Numerical
modeling
2nd REGIONAL SYMPOSIUM ON LANDSLIDES IN THE ADRIATIC-BALKAN REGION
BELGRADE, SERBIA, 14-15 May 2015
Valići Lake Landslide
Interpretation of DEM derivative maps
- Visual identification of hilshade, slope and contour maps
- Identification of historical landslide at the same location
Valići Lake Landslide
Interpretation of DEM derivative maps
- Perspective of hilshade map of wider area of the historical
landslide
- Identification of area of interest of hazard and risk evaluation
-
Ground survey and mapping of landslide features
Interpretation of reacitvated landslide contorus
-
Interpretation of two landslides
Reactivation of landslide in colluvial mass of medium deepseated historical landslide
CLG
2nd REGIONAL SYMPOSIUM ON LANDSLIDES IN THE ADRIATIC-BALKAN REGION
BELGRADE, SERBIA, 14-15 May 2015
LANDSLIDE MODELING
CLG
2nd REGIONAL SYMPOSIUM ON LANDSLIDES IN THE ADRIATIC-BALKAN REGION
BELGRADE, SERBIA, 14-15 May 2015
-
Landslide cross section interpretation for slope stability
analysis
CLG
2nd REGIONAL SYMPOSIUM ON LANDSLIDES IN THE ADRIATIC-BALKAN REGION
BELGRADE, SERBIA, 14-15 May 2015
-
Landslide cross section interpretation for slope stability
analysis
HISTORICAL
LANDSLIDE
Landslide dimension:
• Landslide length =
368 m
• Displaced mass
width = 185 m
• Landslide depth =
28.5 m
REACTIVATED
LANDSLIDE
Landslide dimension:
• Landslide length =
230 m
• Displaced mass
width = 120 m
• Landslide depth =
20 m
HAZARD AND RISK ASSESSMENT IN THE
RJEČINA RIVER BASIN
CLG
2nd REGIONAL SYMPOSIUM ON LANDSLIDES IN THE ADRIATIC-BALKAN REGION
BELGRADE, SERBIA, 14-15 May 2015
Wider area
Historical landslides in the Rječina River
basin
2014..
1750.
1996.
1885.
1893.
1985.
1893. (2)
CLG
2nd REGIONAL SYMPOSIUM ON LANDSLIDES IN THE ADRIATIC-BALKAN REGION
BELGRADE, SERBIA, 14-15 May 2015
Wider area
Natural conditions in the Rječina River basin
Valići Lake Landslide from 2014
Grohovo Landslide from 1996
CLG
2nd REGIONAL SYMPOSIUM ON LANDSLIDES IN THE ADRIATIC-BALKAN REGION
BELGRADE, SERBIA, 14-15 May 2015
Wider area
Natural conditions in the Rječina River basin
Monthly precipitation (meteorological station Rijeka) for three months preceeding
landslide activation
Precipitation (mm)
Monthly precipitation for the period 1958-2013
December 2013
Janurary 2014
February 2014
Wider area
Natural conditions in the Rječina River basin
Landslide
collapse
(before 2 pm)
Cumulative precipitation (mm)
(mm)(mm)
Daily
Precipitation
precipitation
Development of
shear cracks on
the road
Conclusions
•
THANK YOU
•
•
CLG
The results of the described investigations
have been applied for the assessment of
Valići Lake landslide hazard and
risk related to reservoir and dam
site
The determination of rainfall events
necessary to determine temporal
probability of landslides in the area of the
Rječina River valley
Interpretation of landslide hazard
maps from HR DEM necessary to
determine spatial probability of landslides
in the area of the Rječina River valley
2nd REGIONAL SYMPOSIUM ON LANDSLIDES IN THE ADRIATIC-BALKAN REGION
BELGRADE, SERBIA, 14-15 May 2015