Evaluation of quick clay failures and the impact of climate change on slope stability
Typ
Examensarbete på kandidatnivå
Bachelor Thesis
Bachelor Thesis
Program
Publicerad
2024
Författare
Farmanesh, Kiana
Gummesson, Emma
Ryberg, William
Sandberg, Arvid
Modellbyggare
Tidskriftstitel
ISSN
Volymtitel
Utgivare
Sammanfattning
This bachelor’s thesis investigates the phenomenon of quick clay failure,
focusing on the triggering factors behind landslides in Western Sweden and
Norway. The aim was to map a pattern in historical events and with
retained knowledge about quick clay and scenarios in climate change
estimate future slope stability. To understand the triggering factors an
investigation was conducted ranging from the structure of bedrock to the
chemistry of clay particles.
Water is one of the main factors that contribute to the formation of quick
clay landslides and the characteristics of specific clay types. New
precipitation patterns risk increased infiltration and flow in the soil which
raises the importance of efficient risk mitigation strategies against slope
failures. Alterations in hydrology were investigated, and how they affect
parameters defining the strength and capacity to resist movements in the
slope. Climate scenarios were used to forecast the influence of climate
change on the global water cycle and consequently, its impact on future
landslide occurrences.
Historical factors of four landslides were compiled and analyzed. Multiple
simulations of the Tuve landslide were conducted in Geostudio with analysis
in Seep/W and Slope/w for three different sections. The understanding of
quick clay properties, coupled with simulation results, led to the conclusion
that the catastrophic landslide in Tuve in 1977 was a translational
progressive landslide originating from Tuve kyrkväg. The extensive scale of
the landslide was due to the initial slide disrupting the clay, transforming it
into a liquefied state, thereby reducing the shear strength to zero causing the
rest of the area to collapse. The behavior of quick clay is unpredictable and
difficult to estimate the extent of a slide due to the possibility of a serial
failure post an initial perturbation. The discussion highlights the
importance of mitigating strategies and early indicators of potential hazards.
Beskrivning
Ämne/nyckelord
Tuve , Landslide , Quick clay , Saftey factor , Slope failure