Under våren planerar vi att köra ett månadsvis lunchseminarium på en timme om något aktuellt ämne. Det tredje tillfället är den 30 mars kl. 12.00-13.00. Temat för dagen är riskerna med kvicklera som är högst aktuellt efter det svåra raset utanför Oslo för ett tag sedan. Minna Karstunen och Mats Karlsson från Chalmers geoteknik presenterar sina slutsatser; vad kan vi lära från händelsen i Norge och hur kan vi undvika liknande händelser framöver?
Seminariet äger rum på Zoom. Länk till eventet kommer några timmar innan vi startar. Fyll i din e-postadress på länken här.
On the assessment of slopes in quick clay
On December 30th last year, a dramatic quick clay failure occured in Norway, resulting in loss of life and major damage to property. Due to the changing environmental loads, these unfortunate events may become more common. The societal consequences of quick clay slides will become even more pronounced with the ongoing increase in population and the densification of urban areas. Quick clay refers to a natural clay with rather striking properties. The complex geological deposition history and isostatic uplift has led to a formation of a natural material that is meta-stable. A small perturbation can lead to an irreversible phase change, from a compressible solid that can support considerable loads, to a viscous liquid with little bearing capacity.
Natural slopes in sensitive clays are of particular concern, as even those that are stable today, can become unstable in future. The source can be careless engineering and construction, but more worryingly also the processes induced by climate change. Currently in industry, the stability of slopes is assessed using limit equilibrium methods that are based on total stress analyses. Consequently, the impact of climate change on the stability of the slopes cannot be assessed directly, as the coupled hydro-thermo-mechanical processes that link material degradation, deformation and flow in geo-materials are not considered explicitly.
This presentation will demonstrate how the recently developed constitutive models for sensitive clays can be used to simulate the complex response of natural sensitive clays. Furthermore, it is shown that the emerging response at system level is strongly affected by the processes that formed and are still ongoing in the natural slopes. The developed numerical techniques enable to assess the impact of climate change on the stability of slopes in natural quick clay.
Kommande seminarier planeras 27/4 och 25/5.
Vänliga hälsningar
Pär Johansson
SBU koordinator
par.johansson@chalmers.se
