Scour failure of bridges

Abstract

In recent years there have been several bridge collapses in the United Kingdom and Republic of Ireland that have been caused by scour. Towns in the north west of England have been cut off and loss of life occurred. Major railway lines have been closed for extended periods. Although scour is basically the removal of bed material due to flowing water, it has a number of different causes and takes different forms. The paper describes the different forms of scour and looks at a number of case studies to illustrate the different ways in which scour has caused structures to collapse or require protection. The case studies are of railway bridges and are drawn from official investigation reports and underwater examinations carried out by the author. The paper concludes by illustrating ways in which failures due to scour could be avoided by the employment of good bridge management systems.

Structural Health Monitoring for Performance Assessment of Bridges under Flooding and Seismic Actions

“…Scour is the leading cause of bridge collapse worldwide for bridges with foundations located in waterways, [4][5][6] as it reduces the stiffness and capacity of foundations and can cause sudden failure. 7 Earthquakes also pose a significant threat to bridge safety in seismic-prone regions and can cause sudden element failure if capacity design principles have not been followed at the design stage. Unfortunately, many existing European bridges are in this condition, since the adoption of capacity design principles is quite recent in most seismic-prone European countries.…”

Recent Development and Remaining Challenges In Determining Unique Bridge Scour Performance Indicators

“…Scour failures typically occur quite suddenly and generally, without warning, potentially leading to loss of life. Figure 1 shows the Malahide Viaduct, in North Dublin, Ireland, that failed suddenly after a train had passed over it (Maddison, 2012). Fortunately there were no casualties in this event; however, this section of the TEN-T railway between linebetween Dublin and Belfast, was closed for several months as a result of the collapse.…”

Structural Health Monitoring and Design Code compliance for performance assessment of bridges under scour and seismic hazards

“…The increase of the hydraulic outflow speed causes turbulences and vortex shedding (HEC18, 2001) close to the bridge piers, generating local scouring at the base of pier foundations. Scour of bridge foundations is one of the most frequent causes of structural collapse in United States, with about 600 bridges failed during the last 30 years (Briaud et al 2005), but also in Europe, particularly in the United Kingdom (Maddison 2012) and central Europe (Tanasic 2016). In regions prone to seismic hazard, ground motions may induce damages on bridge structural components like piers, abutments and bearing systems.…”