EROSION ON BRIDGE PIERS. EXAMPLES ON EROSION DESIGN

Erosion in rivers and fjords can lead to serious damage of engineering structures. As a rule the best way to control erosion is to change the conditions for erosion as little as possible. It is shown that the supporting soil beneath a bridge foundation can be eroded away to an extent that will endanger the safety of the structure. Piles are sometimes used to prevent instability caused by erosion. As an example, the erosion design conditions for a bridge in the city of drammen is described. High embankments are often used for causeways across fjords, but can sometimes lead to erosion problems. It is therefore in some cases necessary to study the behaviour of proposed embankments projects in test models in order to obtain design criteria for erosion control. Erosion control at Osenstroemmen is described. At ferry terminals it is shown that erosion is a great problem. From model tests design recommendations have been established in order to prevent erosion at ferry terminals. (Author/TRRL)