Use this URL to cite or link to this record in EThOS: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.750634
Title: A probabilistic approach to assess the stability of flood embankments : the case study of the Adige river embankment
Author: Amabile, Alessia
ISNI:       0000 0004 7425 2948
Awarding Body: University of Strathclyde
Current Institution: University of Strathclyde
Date of Award: 2018
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Abstract:
Flood embankments are a key asset in flood defence systems; assessing their probability of failure is therefore important for the evaluation of flood hazard. Flood embankments, however, can reach lengths of thousands of kilometres. Probability of failure assessments are complex and expensive, which limits their applicability on such a large scale. This challenge highlights the need to develop both a simple probabilistic approach that does not require excessive time or computational effort, and an affordable method for the deterministic hydro-mechanical characterisation of flood embankments that can easily be extended to long segments. This thesis addresses these challenges by first focusing on the development of an accessible probabilistic method that accounts for uncertainties in the soil properties and hydrological loading. This approach benefits from the simple First Order Second Moment method while addressing its main limitation, namely the assumed probability distribution of the Factor of Safety. The approach is successfully validated against its ability to capture the annual probability of failure of a segment of the Adige River embankment that experienced instability of the landside slope. The hydro-mechanical model of the embankment is characterised via site investigation and laboratory tests. In particular, the hydraulic model is characterised via inverse analysis of water flow in the saturated and unsaturated zones based on field monitoring data. However, this approach may be difficult to extend to long segments of the embankment, given the challenge to monitor water flow on a large scale. In order to address this issue, the use of Electrical Resistivity Tomography (ERT) for monitoring of water flow is investigated. Results show that ERT can be a valuable tool to quantify water content if a field-specific relationship between water content and ERT-measured resistivity is calibrated. The case study of the Adige River embankment is further analysed to investigate the factors governing the water flow and stability of the embankment. Comparison of the water flow regime between two sections, located within and outside the failure segment, highlights the critical role played by the hydraulic response of the material on the landside outside the footprint of the embankment. This key finding can support the decision-making process when planning site investigation aimed to the stability assessment of flood embankments. These outcomes combine to provide a flexible approach for the probabilistic stability analysis of flood embankments that can be easily adapted and applied to different contexts with limited levels of investment of time and resource. This approach may be developed into a suitable tool for the routine hazard assessment of the stability of flood embankments.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.750634  DOI: Not available
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