Scouring of Bridge Foundations

With climate change leading to extreme weather patterns, record-breaking flooding is becoming the new normal. Recent such extreme events have led to the collapse of several bridges due to foundation scouring (e.g., Kalampaka, 2016). We have developed a 2-step experimental methodology to study the hydraulic and the mechanical part of the problem. In the first step, the hydraulic problem of local scour around a bridge pier is experimentally modelled in 1 g, using the recently developed MTG (J98).

Time evolution of the scour hole: (a) contour plots of bed elevation; (b) cross section at the foundation centreline; and (c) contour plot of the regularized surface used for the 3D printed mould.

The experimentally generated scour hole is then 3D-scanned to produce a 3D-printed mould. The latter is used in the second step to reproduce the scour hole in an N g model, subsequently tested in our drum centrifuge to study the mechanical part of the problem under proper stress scaling. Employing this hybrid technique, we have investigated foundation performance prior and after local scour through vertical, lateral monotonic, and slow-cyclic pushover tests. Our work has quantified the effect of local scour on vertical and lateral bearing capacity, questioning the common simplification of ignoring the geometry of the scour hole, making no distinction between local and general scour.

A mould is 3D-printed based on 3D-scanned surface of the scour hole, and used to reproduce its geometry in the centrifuge model (left); experimental setup for lateral loading in the drum centrifuge (right).

Selected recent publications

Jones L., Anastasopoulos I. (2020). “Miniaturised tsunami generator to model interaction of tsunami with coastal infrastructure”, International Journal of Physical Modelling in Geotechnics, 0 0:0, 1-15 (Ahead of Print) (external pageJ98)