Abstract
Animal burrowing can greatly influence the water pressures in a flood protection embankment and thereby be a cause of breaching of flood defences. However, little guidance and literature is available on this subject. This paper investigates the contribution of badgers, porcupines and foxes to the failure of the levee of San Matteo (Modena, Italy) on 19th January 2014. The proposed method evaluates their influence on the water pressures in the embankment during rainfall and a high water tide. The influence of the burrowing is assessed through a transient FEM flow analysis. Starting from the documented entrances situated in the vadose zone, different scenarios for the internal distribution of tunnels and chambers are proposed. The most likely representative network for the loss of stability of the dike is assessed.
Highlights
On the 19th January 2014, around 6am, a high water level in the river Secchia created a breach along a dike in San Matteo (Modena, Italy)
The current paper investigates the influence of animal burrowing on the pore water pressures to predict the failure mechanism for the Secchia river
The transient flow analysis presents lower pore water pressures that the steady state solution, while, at the inner side, the water level exits at the dike toe due to the influence of rain
Summary
On the 19th January 2014, around 6am, a high water level in the river Secchia created a breach along a dike in San Matteo (Modena, Italy). The report presents hypotheses on failure mechanisms, indicating that internal erosion and macro-instability are possible causes of the breach. The current paper investigates the influence of animal burrowing on the pore water pressures to predict the failure mechanism for the Secchia river. The heterogeneity introduced by the animal burrows influences this trend and the pore pressure distribution. The groundwater flow inside the dike body gives an indication of possible failure mechanisms, which can be derived for several scenarios of animal burrows. The paper concludes over the likely holes distribution and failure mechanism leading to the breach
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have